Strange sound from rebuilt engine...
 

Just started up my newly rebuilt engine (top end) and am experiencing a very loud rattling sound (louder than it sounds in video). See attached video (please excuse my poor directorial skills). It sounds like a freight train. What do we think is making this noise? It definitely does not sound right. I have eliminated the fan/alternator as the source by testing without the belts attached.

Highly recommend you take the car back to the shop that did the top end rebuild and let them figure out what's wrong and fix it :cheers:

Lifters?

yeh, lifters?
when I replaced the exhaust lifters it took until the thermostat opened for them to quiet down, so call it 8 minutes. it sounded like I left a screwdriver inside.

If it isn't the lifters it could be that one of the chain tensioners was installed upside down. Very easy to do.

Pete

LOL. I am both the shop and its first customer

I had a friend over and that was his first thought. His second thought was, "that engine sounds dry - any oil in it?" Ten quarts.

Well, this may be the culprit. I have to say it was so loud I didn't want to go 20 minutes until the first oil change. At 2000 RPM all of my neighbors would lynch me. This is my first time at this so I shut the engine down for fear of doing damage. Now that you mention it it does sound like six crazy monkeys tappin' away with hammers. All brand new lifters.

Well, that's possible too although I looked up the german for top, bottom, left and right and was very careful. I think I took pictures so I'll check.

Well, it needs 12.

Sounds like lifters to me. And the engine will be fine, just fine, on 10 quarts for now.

Yes, correct. I should have been more clear. I put ~9-~10 in which is roughly what I drained out of it.

So with the lifters do I proceed with the 20 minutes 2000 RPM as per Wayne's book with the idea that the noise will die down?

Thanks everyone!

I'm assuming you turned the motor over a few times by hand to make sure all was well?

hows it run?

Yes, many times during the rebuild process. It seemed to turn over with a little resistance here and there. Harder after plugs.

As for it running - besides the noise it seems very strong. No misfires or anything like that. The throttle has a little slack in it but I will adjust that a little later.

Lifters, they need to pump themselves up. Sounds like the tech didn"t do them prior to assembly to get out any traped air or they bleed down during the assembly if there was substancial time between assembly and engine start. should be OK.

Based on this, I'd say its something like lifters needing some time to pump up.

Oil pressure is good I'm assuming?

This sure does sound like a lack of oil issue. Total capacity if you drained everything is more than 9. Did you drain the oil lines, oil cooler etc?

Had a friend do a WB conversion on a cab recently, so the oil system was completely drained as the oil tank etc had to be removed. The car sat for quite a wile before it was restarted. On first restart there was wuite alot of lifter noise, we checked the oil, it was at the bottom of the dip stick, as soon as we started topping up the oil the noise disappeared.

I would get the noise fixed prior to doing the 20 min 2000 rpm run in.

I soaked in oil overnight and installed in rockers but there were several weeks before startup.

I'm getting 1 on the gauge at idle and increasing pressure with higher rpms into the 4 -5 range. No codes or warning lights.

Did the standard drain as in an oil change along with the oil return line by small filter.

My plan for today is to run the engine at idle and let it warm up to get the oil flowing. If noise continues after 15 - 20 minutes I'll check the dip stick and add some oil as suggested. The adventure continues, will report back later.

When i replaced all my lifters 2 years ago, i also soaked them in oil, it sounded like that for probaly 20 minutes or so. I thought i had done something wrong even shut engine off a couple times thinking i was damaging something. Noise eventually went away. All good now except, one lifter on the drivers side exhuast that will start to tic if i idle for too long, but goes away when i start driving.

Hope its just your lifters. good luck

good luck

1 at idle is a little low.

Here's an update. Ran the engine at idle for about 25 minutes. Also added another quart of oil. Checked the oil after temp was up and oil level is at mid dipstick. Now the bad news.

I watched the temp gauge go up to 9 o'clock and then fall. This was at the 15 minute mark. Then it steadily rose to 10. Then 10:30 and stayed there for 5 minutes. I could not tell if the oil cooler came on because of all the engine noise but my guess is no. At some point the oil light came on and I shut the engine down. The noise is still there and this is starting to look like an oil pressure issue. Suggestions?

Did you split the case when you rebuilt the engine, or simply do a top end?

Especially at cold idle. Best of luck in finding the issue.

If the oil temp went to 9 then fell your tstat opened to the front cooler when this happened. Oil pressure of 1 is low at idle. Check the chain tensioners and the oil tube feeding the cam towers on each side. You can install these upside down also so they won't pump up. The gasket that installs on the tensioner should be checked to make sure you are not obstructing the oil passage to the cam towers. Also check that you did not mix up the oil pressure relief valve springs/parts. I would take a plug out of each cylinder and turn this by hand to make nothing is binding. Steve brought up a good Q as to how far the motor was taken apart.

You can feel if the cooler is open by putting your hand near the cooler or feeling the top of the fender for heat. And you can feel if the cooler fan comes on by putting your hand under the grille on the bottom of the bumper and feeling for warm air blowing out.

Update 2
 

Just a top end. Did not split the case.

These are next on my list. When checking the tensioners can I just take off the 'cap' and see if the small openning is there feeding oil into the cap passage? So when checking for binding what should I look for? Slightly hard to turn? Very hard? Oil pressure relief valve was not touched.

I have confirmed that the fan for the oil cooler fan up front is not working. I used scantool and OBD1 calbe and then used the 'test outputs' function. What typically goes wrong with this unit?

Also, I restarted and the pressure light did NOT illuminate.

I doubt if its a tensioner or ramp - the noise sounds like its timed with the rotation of the engine, and given you did not split the case, its likely valve train, timing or head clearances. If you sent the heads out for machining, the only risk there is the change in the deck height if they machined a lot off the head to flatten it. That does not happen that much since you really need to machine a bit to have this happen. It can, but its unlikely. That leaves us with timing issues or valvetrain. If the timing is off, the place where you can get noise i the collision with the heads and valves, again unlikely unless you are wayyyy off. So the most likely is valve train, which is around lifter pressurization. I find that pre-filling in the lifters really does nothing, putting them into the rocker and installing them will allow most of the oil to drain anyways. I do find it more effective to pre-pressurize the system by cranking the engine over with the DME relay pulled -> I assume with a new engine rebuild you did this?

So the real question is to let it run a bit more to see if the lifter pressurize, or start to tear it down looking for visual clues? Tough one to answer, I would do a few things first like pull some easy to get at plugs just as a check to see how they look, I would then pull the DME relay and crank the engine to see if any metallic noises are made (it should be fairly quiet), and if you want to run it, I would spend some time trying to see where the noise is from using a mechanic's stethoscope (or in a pinch a long screwdriver held to the ear...). You can also do a quick compression test and if possible leakdown to see if the timing looks correct, if its way off the valves will not be seated at TDC.

Let us know how it goes, best of luck!

Cheers,

Mike

Normally 2 to 2 1/2 at idle, if I recall my gauge readings.

Mike, I did do the pre-pressurization per Wayne's book. My first task is to troubleshoot the oil cooler fan issue and go from there.

The idle pressure seems to vary a bit car to car, and also on oil weight/brand, and temperature. You are right though most of the cars I have worked on will idle at 2 or more, even a full temp.

You should install a fan override anyways, and you can use that. In the meanwhile, you can force the fan on by removing the right headlight and unplugging the sensor.

I think the oil-cooler fan issue is a red herring and not related to the mechanical noise of the engine. To me, that is the first problem to solve...

Cheers,

mike

You are probably right. I switched the relay with the a/c and the fan now operates at slow and fast. Seeing the oil temp up so high freaked me out. The adventure goes on.

Well I was going to say that last summer when I didn't start my car for about a month, upon start up it was making a similar noise to yours. Probably not as loud but the valves were clearly ticking. It took about 2 significant drives for them to adjust to their normal sound.

I don't know if any of that helps, though, since it seems like you have another issue w/ the temperature/oil-cooler.

Peter,

You can pull the retainer cap off the tensioners and take a peak. One way to find if the tensioner is an issue is to pull the coils and turn the car over a bit without it running. It will make a very mechanical sound. You can hear the chain slap at the chain covers without the engine running. You changed all the lifters and it's pretty hard to put them in wrong. Did you clearly mark the exhaust and intake lifters? They are different at the top for oiling the cam shaft. If you have them reversed this would cause oiling issues.

Yeah, 2 or slightly above seems to be about right...but thats when warm.

If OP saw 1bar when not warmed up, that would be significant cause for concern.

I'm pretty sure the rockers are aligned properly vis-a-vis intake exhaust, however, this could be a second line of inquiry should the below fail.

I've been doing some searching/reading and came across someone on another forum who installed the tensioners upside down. They described the noise as a deisel truck sound which is exactly the sound I have. So I will go with that idea for now, remove the caps and take a look.

Just to confirm - I should be seeing the small hole at the end of the tensioner indicating correct orientation? If the hole is not there that would indicate I have found my problem?

Thank you all for the help! I will report back my findings.

So, today, on cold start-up I have 1.5 which slowly drifts down to 1 at idle. When I kick it up to 2K rpm I get a pressure increase in kind. More to come tomorrow...

yeah, thats a definite issue. even with a 0w-40, you should see at least 3+ bar on cold start.

Time to stop guessing and take an actual oil pressure measurement with an external oil pressure gauge. Tick that off your list and move onto the next possible cause.

You should see a small hole at the top of the tensioner. The retainer cap has an oil passage on each side that allows oil to flow in and pump up the tensioner. That oil passage then continues onward to the feed tube you see located that connects to the cam tower. If your restricting that flow then you see how vital it is to get it corrected.

Left tensioner: oil supply hole points up.

Right tensioner: oil supply hole points down.

When you look at the covers, it'll make sense.

Mid-day update:

Removed left tensioner cap. Oil hole pointing up. Confirmed it is the left tensioner (longer of the two). Cleaned and resealed. At least the left is correct.

Before moving on to the right I started up the car. Pressure at start-up: 4 Bar. As the engine warms up the pressure slowly drifts down to below 1. Pressure bounces up with RPMs. At the 15 minute mark the pressure light came on and I shut the car down. Noise has not abated.

I think you should stop running the car.

Are u going to try anything that i suggested?

Cheers

Mike

Agreed.

Yes, I tried running the car to get the lifters to pressurize. Not working thus far. Also tried pulling dme relay and turning the engine over. No unusual noise while doing this. I do not have a compressor at the moment so I can't do compression/leakdown yet. Did I miss anything you suggested? BTW, the heads were done by Steve at RS.

Hey Peter,

Did you split the case for this rebuild?

If so, there are some very serious issues about oil pump sealing rings that cause VERY low oil pressure.

Let me know!

Ok, did you;
- quick pull of some plugs to check if they looked good?
- use a stethoscope to try to locate the noise?
- compression test (required no compressed air)?

#2 above is a good one because location may help - it also may be hard to determine. I doubt if its tensioners unless it's allowed the cam timing to be out by skipping on the sprocket, but keep confirming the direction is correct.

Lets review the rebuild a bit - did you do the valve clearance test? I seem to remember you had the index pin on the cams so they cannot slip, right? You timed to 1.0mm or ?

The noise is regular and with the engine rotation - I assume if you rev it up the noise frequency also increases?

I also agree to stop running it up to full temp - use short bursts if you think you can chase this down externally, or be prepared to start the teardown process. You might be doing more harm than good by running it.

Oil pressure is a red-herring I think, or might be a side product of the actual cause, but I agree with Alex, check with an external gauge.

The chances of getting a bad set of lifters for all 12 is small, but there have been batches of lifters lately that are failing - I recently had to do over a lifter change because of that. In that case, they started failing in a few miles of installation, not right away....

If you can use the stethoscope idea (or a screwdriver) to at least find out is the noise from under the valve covers, or chain covers, or where, that would help.

Cheers,

Mike

No. Top end only. Did not split the case. Perhaps the pump and or seals are going?

Steve, he said earlier it was just a top end, not splitting. I assume he did not re-ring, so its all around the heads, cam carriers, timing, etc.

Cheers,

Mike

We are chasing some possible red herrings here - heating up too much, or low oil pressure, noisy -> you need to be systematic and eliminate variables.

Get an oil pressure gauge and use it to confirm if your oil sender is hooped.
Again, try to isolate the noise more to figure out if it can be localized. Where is it loudest (can be misleading but might give us a hint).

I doubt if your pump is going, but since you dropped the engine, you do need to re-hook up the car - I would double check the rubber line on the feed side (its between the tank and the solid line that runs to the engine). See if that is collapsing, if so it may be something in the tank - again likely not.

Cheers,

Mike

Are there galley plugs in the cam towers that could have been left out?

My responses in ALL CAPS.

It does sound like pressure loss somewhere that is not providing the oil to the lifters - there are also bridges from the block to carrier that need to be in place - but there would be oil everywhere if not there. The cam carrier does have an internal spray bar for the cam and passages to feed the lifters, etc.

Where there any modifications or removal of plugs in the cam carrier?

Cheers

Mike

Did not remove or modify plugs. Oil bridges in place not leaking.

Hmm- if we think around the idea of oil loss, where else can we lose oil that is internal on the top side of the engine?

The rocker shafts are keyed so I seem to remember they are almost impossible to get wrong - but they can be flipped, but they will not look right when installed. Did you take a picture like this one to confirm the shaft is oriented correctly? (if not, the oil feed hole will be blocked and the lifters will not pressurize).

http://www.pcarworkshop.com/images/t...33_-_small.jpg

Did you change out the lifters? I cannot remember if you did or not. If might be worth taking a valve cover off the engine to check things - should be easy given all the bolts are newly put in.

The overall carrier is pretty simple, not many places to go wrong....

http://www.pcarworkshop.com/images/t...37_-_small.jpg

Cheers,

Mike

Pulled two plugs. The one on the left is Cyl. 2 lower. The one on right is cyl. 6 lower. Plugs are brand new.

No. 2 is much blacker and the central core is black. No. 6 central core is much lighter in color. What does black indicate?

Attachment 701415

Attachment 701416

Attachment 701417

Are those brand new with just the startup time on them? They should not be black - that is incomplete combustion. Do a compression test to see how well the valves are seating, it also checks your timing (i.e. low compression may mean your timing is off and valves are left open, although that would usually result in contact happening).

I am thinking lifters OR maybe a mistake on timing? -> Have you timed these engines before (i.e. is it your first time?).

Yes, of course. Actually, that was my next thought as this is at least something I can do without dropping the engine. Yes, I changed out all the lifters. They are new.

Yes, the spark plugs are brand new. Yes, this is my first time doing the timing. I pretty much followed Wayne's book with the exception that I did each side independently; left, then right. And I did backdate to the pin method.

Excellent,..thank you. Do not worry about your seals or pump.

Sounding like an oil flow issue.

I see Bobt suggested this previously...
Chain tensioners installed properly?

Maybe I missed it but I didn't see that you checked it off the list yet.

EDIT: Scratch that, found it, you checked it off
Hmm...

You didn't remove one of the pressure relief valves, right?

This could be completely off-base, as I have not had a 911 engine apart, but have we ruled out piston to valve slap as a result of the timing being off? As in, only barely off causing a slap instead of full contact to lock the engine or break a valve?

edit: Now that I think about it, I'm not sure that is the case as it seems it wouldn't be possible for it to happen on multiple cylinders without ingesting a valve.

If we're still thinking it's a lifter........... That low oil pressure at idle thing is odd for just a top end.

OK, I'll throw up something I remember doing at the track one time on a guy's car. (Steve will probably cringe as he continues to read.) This is from the solid lifter days, but there was a noise that we'd now say was a collapsed lifter in the 993 era. Couldn't figure it out. Rocker shaft slid out? No. Valve adjuster broken? No. Broken spring? No. Finally, we took an individual cylinder's rockers off, times maybe 2 or 3 (we'd kind of identified which side it was on), and started the car each time. Bad cam.

Not saying we're looking for a cam issue here, just that taking an individual cylinder out on a one-by-one basis will probably identify what's what.

You back dated the cam sprockets. What shim setup did you use on each side since the back dating uses a different set of shims. If these are out of place you chains will not align well and there is not much room in the cam housings. Did you tension the cam chains while doing the timing and use a solid rocker to set the timing?

I asked him if he measured the valve/piston clearances all around TDC, he did.

I would take a step back and forget about the lifters and oil pressure... If it was not making a racket would you be worried about idle oil pressure?

It could be an ignition problem? Have you isolated one of the distributors and seen the effect of removing a plug wire? Are the distributors (meaning plug wires) in sync? I assume that you may have replaced the wires or at least removed them from the caps... Did they get replaced in the correct position? You (we) could be hearing secondary detonation?

When I did my top end last spring I got a cam 180 out and it made a noise not unlike yours, had a somewhat smooth idle but couldn't rev for beans.

Just my $.02 worth... Good luck...

Like others suggest, I would not run it very long at a time until I decided to start over. Cam timing (indexing) can be accomplished, effectively with the engine in he car...just ask me how I know!!!

Yeah, good idea, I was thinking it might be beneficial to have more details on the build and timing aspects - this is why I asked if he has done it before, but there are a few tricks and double check you can do.

One of the reasons I am asking him to listen with a sethescope or screwdriver is to isolate the sound - is it valve train or chains?

He will need to pull a valve cover or two, and run the car. Chain covers might have to come off next...

Cheers,

Mike

I guess you did not follow my engine rebuilding thread a few years back ;) - did exactly the same thing, but in my case, the engine would not even start. You actually could start your car which I find strange ... and I also retimed while in the car - its not that hard... as compared to the rebuild anyways.

I would have thought if it even started it would have been way more lumpy than this car. Not sure though, I only have one data sample.

http://www.pcarworkshop.com/images/t...327_-_0162.JPG

Mike, actually I did follow your thread but had to drop the engine, a you did, due a leaky cam gasket. When I put it back together I screwed up and had to dop it again, this time with success.

Hey, we are the "backwards bro's"-> Jerry Woods told me that the mistake of timing the second bank without 180 rotation is one of the most typical mistakes. Peter (original PO) confirmed with me via PM about that rotation -> but through text and not being there, I hope it went OK.

Its going to be interesting to see what's up on this one. THe interesting possible red herring is the oil pressure, even if the cams are out, the pressure should not be dropping..

Cheers,

Mike

Count me in the club, too. And yes, I've started one of these three cylinders-on-a-common-crank creations.

Don't think I've ever mixed the cams up side-to-side though. Always been diligent about that from the earliest Bruce Anderson comment about the natural "L" the left cam has with the opposing lobes.

Ok, so lets discuss this a bit. Ken/John, when you guys miss timed the cam, did the engine start, and how did it run?

In my case, I could not even get the engine to start, but I suspect if it did, it would be much rougher than Peters (the OP). The ignition would be firing a piston at the opposite side of the cycle than expected.

Cheers,

Mike

And the Right being "Rabbit Ears" with the lobes being close together.... yeah, I remember Bruce commenting about that.

This was back in the carbs-on-everything days, so a unsmooth runner on startup would be somewhat expected. Especially with the stupid aggressive cams we all wanted back then.........

Was funny to see that in the book when he finally wrote it. (For those of you who aren't aware, Bruce has pretty much been hospital bound for the past year. For those of you who've maligned him on the Excellence pricing guide over the years, know that he was truly generous with his time in cluing me in to rebuilding my first 911 engine when I wasn't so clued in at 18. My life would be wholly different today if it weren't for him and the Garretson Enterprises gang.)

Another possibility, yes. I had both cams reground at Elgin and the rockers were reconditioned by Steve.

I used the original shims as they were. The car is a very early 95 meaning it has the 964 sprocket assemby. The only change I made was the addition of the pins. I wonder how that setup would NOT slip as it seemed to have only a 'friction fit' setup to begin with? And yes, I tensioned the chains with a device exactly like Mike J. used. Yes, I used a solid rocker with the .1mm offset.

Thanks John. No I have not done the distributor sync thing. Do you mean pull the coil wire on one and then restart the car? then repeat with other distributor?

As for the wire order. I did NOT remove the wires from the caps. And I have checked the routing/order of the wires at least 4 or 5 times to rule this out. The wires are relatively new, under 1K, and worked fine prior to rebuild.

Here are some pix from during the rebuild. The cams are correct for left right. The Cam pic is of the LEFT side. Notice the 247. Correct for left side. Allso followed the "L" and Rabbit Ears rules to be sure. Second pic is of right side FWIW. I'm off to get stethoscope....

I'm not reading all this, but cold weather and a rebuild... You sure it isn't lifters? What weight oil? (Thick oil + cold weather) x rebuild = lifter that will take a long time to come up.
Is the sound comming from the bottom left?

Hi Calvin,

Read through the thread - there are a series of problems being identified, like oil pressures, the noise, heat, etc. Lifter have been discussed and are not off the table as a source - the question is there an issue around pressurization that is greater than the lifters itself, and possible related to low oil pressure.

Peter is going to try to isolate the location of the sound which will give us a better clue as to valve train or chains.

He has run it a few times to full operating temperature, it may still be possible that the lifters are not pressurizing just due to being stubborn, but its not clear.

He is also in California, but not sure where to see how much temperature is impacting this. I am sure he will respond.

Cheers,

Mike

Location: Bay area. Temps 45 - 58F, currently 49F. Not exactly balmy but not cold either. I suppose I could be in the Blizzard Nemo. The oil in the car is Brad Penn 20w-50. All input is welcome. Thanks.

Have stethoscope. Will report back soon.

The Doctor.

All I can tell you is that I am here for moral support. I have been in this situation with everything from cars to computers to HVAC.

Hoping it turns out well for you.

Peter, I would be surprised if it didn't make all that racket considering the conditions.
20-50 oil
50 degrees OAT
Lifters being out of service for an extended period.

It's going to take more then idling the car to operating temp.
Drive it, for 20 minutes with the Baby gloves off.

I just experienced this same condition with a friends car here in AZ last weekend. The 20-50 was literally pouring like syrup on a cold to "us" day. Lifters would not pump up on the oil top off procedure at operating temp. His motor was out for about a month. I believe the lifters have a hard time accepting 20-50 but they will with a good drive.

As far as break in, we used to redline RSR motors on the dyno the moment they hit operating temp. The way these motors are built and coated it isn't an issue.

Thank You. That actually means quite a lot to me. This has been a bit of an emotional rollercoster ride. One spends months and quite a bit of cash doing this and when it is all ready to go you get thrown for a loop.

I honestly could not have done anything to my car without the support of all the truly wonderful people here. This is truly a great place.

Having said all that I am remaining positive and trying to be objective. Step by step, even if I have to rebuild it all over again I will get it done. I will get the best of this machine.

Peter,

You def do not have the cams backwards because that would be apparent when you go to add the PS gear back on right side 4-6 bank. I would not run this until you have checked it a bit further. It would be really depressing to damage it when your so close to getting it right.

Have you tried driving the car just down the block? I know it's a big risk, but it may tell you something???

I'd imagine if it's mis-timing, there would be no power or it woudn't run right.

Or if the lifters didn't pump up, it would be noisy but otherwise work fine.

Comment???

Mid-day Update - The Drama Continues:

So, here I am, ready to go with stethoscope in one hand and compression tester in the other. I decide to do compression first. Hose goes in to Cyl. 2. Fuel pump relay removed. Coil wires disengaged. I turn the car over and read the dial. 95 PSI.
This seems off so I check to make sure I have the hose fully threaded in. I turn it clockwise. It spins. Aha, it is not tight. So I turn it counter-clockwise and guess what? It continues to spin. I realize now the connector is threaded into the spark plug hole and I can't get it out! The hose has lost its grip on the connector. :banghead:

Fast forward two hours. I have removed the rocker panel and finally figured out that to get the connector off I need to remove the hose in order to get a socket on it. My sockets are all metric. This thing is SAE, nothing fits on it. I get out a very long pair of pliers. It wont budge. Next, I get out a 3mm t-handle allen tool and it fits perfectly in the tiny center air hole. A quick twist and it is out!:jumper:

Moral of the story? Good tools cost more but they are worth it. I rented the compression tester from Autozone. It was free with deposit. Nothing is free.:crying:

Thankfully, I have a good quality hose from my leakdown kit and I can use that. Shoulda done that first. The silver lining was I was able to take pix of the cam tower. See next post....

Hopefully, it will be as simple as this.

Yes, A good idea. I have not tried driving it as I was following the break in procedure in Wayne's rebuild book which called for 20 minutes 2000 RPM, oil change and THEN drive it. I don't want to ruin it so I will go cautiously from here and do whatever tests I can before going on a ride. More facts, objective data, etc.. and I will be more comfortable with risking it then. Thanks.

Ok, here are the pics with the rocker panel off. While here I will remove the rockers and inspect the lifters (I will post pictures). I will not be able to get to that until tomorrow as I have social functions tonight which will be a nice break. Anyway, here are the pix from lower 4-5-6 (exhaust):

A few more. Everything looks OK, Yes?

Totally agree.

You havn't even had it past 2,000 yet?

Your putting yourself through a lot of undue stress, I wouldn't expect it to run any different then it is.

Drive it hard, come back and post a smile.

pretty easy to suggest when its not your $1x,xxx on the line

I can't help with any real information...but this definitely looks like a good for me to jump in....so here it is....+1

Just trying to help as I have experienced this on many, if not all 3.6 builds. Watching The video and knowing he only went as deep as the heads, I again say drive it!

The lifters are not pumping up on idle oil pressure.

Cams reground, rockers refurb'd, valves reground also?

I tried to catch up with everything in the thread so apologies if I missed something but...

There are oversized lifters available for rebuilds.
Not sure what you have installed or what was taken off of the cams, valves...

This is an encouraging note and I certainly believe and appreciate what you are saying could be the case. Perhaps you are right. However, as much as I want to drive it and enjoy it, I am not in a hurry.

+1

1. Cams regound. Yes
2. Rockers Refurbed. Yes.
3. Intake valves reground. Yes.
4. Exhaust valves reground. No. New installed but I think they are ground anyway.
5. New rod bearings and bolts also.

Steve W. advised me as to which lifters to get. They were the 'standard' ones: 993-105-141-05.

I spoke to Dima Elgin about the regrind process when I had the cams done. I was curious as to what it would do to the overall geometry of the set up. His answer was that as long as the rockers are redone everything will align properly. It would seem to me that if you remove material on one end that the other end would be that much farther away from the valve. Anyone?

What pressure is required and for how long?

Calvin might be right, now that i think back to when i replaced all my lifters 2 years ago, i idled the car a couple of times for 20 mins or so, and the noise didnt stop. At that point i thought what do i have to lose so i took it out for about 15 mins and drove it HARD, magically noise stoped as the lifter must of finally filled with oil.

Why not try some of that quiet lifter stuff? I know it works in MBZ and BMW's.

Thats correct. The valve lengths were corrected to ensure compatibility with the standard ones. This procedure keeps one from having to buy the uber-expensive oversize ones.

New valves require grinding as well as length corrections and both were completed.

As above,.....

Did you have a chance to located the sound? (I am travelling right now so my postings will be erratic - was hopefully that between checking it got solved... !)

Cheers,

Mike

I followed this thread sporadically mostly on my phone, did this get addressed?

I just drove my car,, and as a datapoint --

Up until minute three the pressure gauge was pegged at 5. After that it started to drop a bit, and until minute seven was at ~3.5.

First time it dropped below 3 was at the ten minute mark.

All observations were at idle (of course), though I drove the car right after starting it.

OAT was ~40F. 15W-50 oil.

Hope you get it resolved soon, good luck.

Not yet. Today I am inspecting the lifters/rockers in exhaust 4-5-6. Then re-sealing the cover. Then compression test. Then sound test.

That part is not solved yet. I am concentrating on zeroing in on the sound source. Will move on to pressure later.

One thing I have learned from the shop manual is that on a warmed up car pressure at idle should be between 2 and 2.5 bar. AT 2500 RPM oil pressure should be over 5 bar. I will need to test this with an external gauge.

To be honest, I think you should reverse your plan. Its very possible that the noise is the result of the low pressure

Agreed

Here's a quick update. Not much to report.

Waiting for a friend to bring over a compression tester tomorrow. A couple things I have done:

I had someone else turn the car over with the DME relay out to check again if any strange sound is present. Nothing heard without stethoscope. I put the stethoscope on the cylinder fins and heard a clicking. It just sounded like the piston moving back and forth. If the valves were hitting the piston wouldn't I be able to hear it?

Put the DME back in and started it. With stethoscope I checked the rocker panel. Loud tapping like a very fast buzz, buzz, buzz. Then I tried under the car at the head cylinder junction. I heard the same sound at a higher frequency. It seemed to be the same sound at about the same volume reverberating over to this spot. This is very hard to do without experience. I then checked the head on the combustion side and then the cam side. Basically, the same sound at the same volume. The same thing on 1-2-3 as 4-5-6.

Bottom end has similar sound but at much lower volume so its coming from between the pistons and the lifters. The chain housing seems much quieter. The tap-tap-tap is not coming from there.

The pressure light did not come on but I only had it running one or two minutes. I know some have said the low pressure could be causing the sound. I'm just trying to do one thing at a time.

Watched the video several times, and I do not feel it is timing related, I like the smoothness of the engine
Have you had any issues removing installing the heat exchangers ?
could you please just recheck the bolts ?
Did you put the seals between head and exchangers ? straight side to head - convex to exchanger

No issues that I recall. Yes, I put in new seals but I did not notice these had two different sides. Could that cause a lot of rattling? The bolts/nuts were torqued to spec. I will check.

No , if the seal is reversed, it does not cause rattling.
Did you tighten the exchangers, then you tightened the cat ? If so...I once broke a manifold stud like this.
Try to check all exhaust man. bolts, to be on the safe side.
I wish if you could double check the head bolts as well, not the torque, just if they are ok (no loose ones)
regards

The Cat was already attached to the heat exchangers. I will test all the bolts anyway.

Regarding the head bolts I went thru the torque down procedure in Wayne's book: Torque, then 90 degree turn. I will check the ones I can get at just to be sure.

What is the oil level in the engine when cold. Not the dip stick level. Where in the engine, above oil return tubes, bottom of the chain housing? etc.. Thanks.

when its running?

Cold or hot, when the car is running, there should be almost no oil in the case itself as the suction side of the pump is sending the oil back to the reservoir.

After you shut it off, maybe 1.5 quarts or so drains back to the case, but it shouldn't be ridiculous. Where that gets you in terms of level vis a vis components, I'm not sure.

When I checked the left tensioner for proper orientation I took some pictures. Look at this picture. This is the top of the left chain housing. It is full of oil. The car is off/cold. I don't think this should be looking like this. Thoughts?

This is helping explain the low pressure. Make sure you do not have the breather hoses mixed up on the oil tank side. This can also cause a big imbalance of oil dropped in/out of the tank system.

I just checked the breather hoses (3) and they appear to be correct. The large diameter one goes from the lower tank opening to the breather hole atop the engine. One of the smaller lines connects to a larger line behind the airbox and goes into the black "L" hose at the rear of the throttle body. The third line (longest) goes from the tank to the spout directly in front of the throttle body. Does that sound correct? The hoses were never disconnected on the tank side.

Another thought - could there be an oil blockage (I'm thinking at the bridge into the Cam tower or at the small hole in the large gasket chain housing- I used 3bond on that gasket and it could have oozed into that hole). Would a blockage in either of these two spots cause the chain housing to fill with oil as per photo?

Definitely check bridge tubes. If you added sealant it very well is clogging the passage and that is an oil path with no where else to go. That oil path feeds the cam towers, cam shafts, and into the lifters.

No, sealant on the bridge tubes. Only on the gasket. Will check.

oil pressure.
 

hello, first off i not a 993 engine expert. but very mechancal inclined.

1. did you have good oil pressure before the top end?

2. you said you had the lifter reground, did you blow the oil hole in the rocker to clear debre? if not that could clog and hinder the lifter from pumping up.

3. also were the rocker rebush/ new bushing?

4. if the lifters are collapsed and not pumping up this can be verified by running the engine, not long and then pulling one distributor cap and looking at what cylinder its closes to firing on and remove that valve cover and checking for rocker play, you do not want to turn the engine over. the rocker should be tight if not completly on top dead center . a excessively loose rocker mean they are not pumping up.

5. like i said im no 993 expert, but the supply oil for lifter comes from head and transfer via the rocker crossbar, is it possible you dont have these installed correctly.

6. did you use any sealer on the bridges ?

7. did you have any work done on the cam towers?

8. cant you remove the lifter and prime by hand?

low oil pressure.
 

i forgot

i know this mAY SOUND STUPID BUT DID YOU INSTALL THE LIFTER UPSIDE DOWN, DONT KNOW IF POSSIBLE BUT COULD CAUSE LOW PRESS AND LIFTER NOISE.

The lifters may not be pressuring up because I have only run the car at idle. Others have commented that this will not be enough rpm's to pressure up the lifter. What do you think of that? What rpm's are required and for how long to pump them up?

No. I installed all with the swival head facing the valve stem. Thanks for your help.

it would really help you out if you run the car briefly and and pull the cap to see which cylinder is just about to fire and just pull that valve cover and see how loose the rocker is.

also you never stated if you verify the right tensioner orientation unless i miss it. you did say you checked the left.

i can tell you this that a tensioner will pump itself up with just an idle only takes a minute or two. i read on other rennlist poster that even new lifter required a spirited drive to pump up. but if you can run briefly and check the cylinder thats a bout to fire and see if those lifter are loose at least you will know that that the problem.

you stated that the valves heights were ground to compensate for the cam reground so standard lifter could be used. ok. do these lifter snap into the the rockers or just slide in. if they just slide in and they are not primed all they way up i could see why they are a bitch to prime on their own.


so lets say that the geometry is off and even if they are fully primed and the gap is too large, they are going to rattle like crazy.

i know your stressing, but the oil pressure thing althogh im portant i thinks thats fine.

when you installed the rockers on a pacticular cylinder hopefully at top dead center. was there play??

if you look on rennlist you can see what a lifter look like when primed and extended.

Ok, what do you mean by loose? These lifters basically snap into the rocker. Do you mean loose in that there is a gap between lifter and valve stem?

lifter
 

correct


check your pm

I'll have to look to see what it should look like.

I for one definitely do not think that the oil pressure issue is a red herring... Even if you're engine was totally quite, if you were only getting 1 bar of pressure, and a low pressure light after 20 minutes, that would be a no no... I bet that if you track down the pressure issue, you'll stop your noise.

Herr Vorsicht,
Subscibed, as I'm eager to see what you find.

This thread clearly shows what a wonderful community the 993 board is.


Andreas

There seems to be 2 schools of thought here. I am definitely going to check the pressure via external gauge.

Any ideas on HOW to track down the pressure issue? What would cause that light to come on after 20 min?

Ja bestimmt! (Yes, certainly!)

Peter, until you have good oil pressure I would not high rev the engine as suggested. If the posters who follow this theory are willing to pay for and rebuild your engine then go for it. Turning the engine over without it firing should still build reasonable oil pressure.

Maybe I missed the answer to this issue--several pages back you showed a #2 cylinder plug that was wet and fouled. Not sure what this means in regards to the oil pressure issues; likely not connected, but still it has to mean something in regards to the way the engine is running.

I have been travelling so missed a bit of the diagnosis - sounds like some progress.

If we are going with the idea of its not timing, and pressure or oil feed related, you can do a quick check of that - just take off a cam cover, take off a lifter, and crank the engine over with the DME relay pulled - you should get a nice squirt of oil out of the hole that would feed the rocker shaft.

Cheers,

Mike

Mike, Welcome back.

What do you think about the left chain housing being full of oil when cold and looking through the chain tensioner retaining cap hole. That seemed odd to me but I really don't know. See post #117 on page 8.

While travelling (just got back), I have been reading the thread via my iPhone, so its been harder to see the pictures... :)

The thing is, its very unusual to take this tensioner off on an active engine, so I am not sure what it should look like. I would think the chain housings should not be full of oil - they will have oil splashing like crazy when running, but to have oil filled in the housings is not good. I cannot make it out in the picture though - is it a solid oil level at the bottom of the tensioner hole? Did you poke at it to make sure it was not a oil-film?

Looking at this picture, you would need a LOT of oil to fil this up -

http://www.pcarworkshop.com/images/t...308_-_0022.JPG

You can always drain the sump to see how much you have in the engine- you should get a 1/2 litre or so. If you get a few liters, then there may be an issue on the return side getting oil back to the tank. Excessive oil in the sump would cause all kinds of issues.

I have been trying to think of what oil-circuits you might have touched during your rebuild just to see if we can think of something. The fact that an oil-blockage or issue could cause the symptoms you are seeing (noise lifters) makes it more of an avenue to explore. The darkened plugs indicated also bad combustion, which may be possible if the valve train is not working properly.

Ok, so you dropped the engine, and did the heads. We might need more details, be you likely worked with but have you checked all these to make sure no kinks, blockages or problems exist? (not sure how to check some of these...):

- the oil feed line from the tank to the pump inlet on the case
- the oil return line from the case back to the tank
- the oil bridge for the cam carrier
- case venting hoses
- oil filters

Do a quick check of the oil level in the sump by draining it at the sump drain, at the most you should lose just a bit of oil. If its a lot, that might indicated an issue.

Cheers,

Mike



-

oil
 

You know the tensioner are different. The left side has the longer tit and the right side the shorter. I believe the left side is also taller. You need to check. I really think this is your problem. Did you know this?

Not sure if this is helpful. I certainly can not makes heads or tales out of it. Any audio guys out there? This is the sound spectrum from the video from 9.8 seconds thru 11.1 seconds

I have confirmed the left side tensioner is the longer one and is in the proper orientation. I guess my next step will be to open up the right side and make sure that tensioner is pointing in the right direction.

Mike, I will go this check later today when I can get to the car (busy now).

Yeah, this could cause oil pressure problems and loss of pressure to the lifters, given its all on the same circuit. Worth checking for sure, but I think he already did.

http://www.pcarworkshop.com/images/t...07_-_small.jpg

Oil tensioner right (bank 4-6), oil supply bore points down, the spring retainers are marked with "oben" (top) and "uten rechts" bottom right.

Oil tensioner left (bank 1-3), oil supply bore points, spring cups are also marked "top" and "RH Bottom".

Cheers,

Mike

Have not done right side yet - on list.

Peter,

If the case is filling with oil you should check to make sure the soft line leaving the engine by the axle is not crimped or restricted. I have even seen someone forget to remove a plug placed on the line to the front cooler and put a hose right over it during reinstall. I would also consider changing the oil pressure relief valve and oil pressure regulator. They are not to hard to get to and if the relief valve sticks open you get low pressure and oil dumped back into the case. (see the diagram I posted prior). Pull the drain plug from the bottom and see how much oil comes out. You can always put it back in if it's perfect.

sounds similar to what I said - :)

Like the idea of checking if the pressure relief is getting stuck - but checking the oil level in the sump first makes sense...

Cheers,

Mike

:D^^^^^^^^^^:D

agreed and an easy check. Lots of oil then it's not getting out. That would mean low pressure at the sensor, lack of oil at the cams and a pond in the bottom end.

I feel the frustration that you be going through!!!!
May you get to a good solution soon!!!!
There are no short cuts, just the right fix.
Good Luck!!!!!

Quick Update.

- the oil feed line from the tank to the pump inlet on the case

Visual Inspection. Looks OK.

- the oil return line from the case back to the tank

Visual Inspection. Looks OK.

- the oil bridge for the cam carrier

I removed the left hand oil bridge and cranked the engine. Oil is coming out of the chain housing where it connects to the bridge. I will check right side after I chain chain tensioner on right.

- case venting hoses

Three breather hosed from oil tank to engine/throttle all check out.

- oil filters

Not sure what to check - when I drain the oil I will remove and inspect.

Hopefully get to this tomorrow and report back.

As suggested will drain this hopefully tomorrow. Then think about pressure relief valve, etc..

Thank you. We'll get there...

Checked compression on 4-5-6.

All at 150 PSI. Will get to 1-2-3 tomorrow.

What should the compression be at this point? I would think it will increase when rings are seated at higher rpm's.

info
 

check your pm for a link

150 is low, but given all the cranking and limited run times, you may run down the battery a bit. A strong starter/battery can affect compression.

I'd say you would typically see between 180 and 220psi on an NA car.

For reference, my 8.0 compression ratio 993 Turbo returned 150psi in almost all holes.

Yes, the battery was very low when I did this. Charging tonight.

Most of my mechanical "talent" comes from listening to click and clack, reading the hack mechanic in the BMW CCA Roundel and the tech advice columns in the Roundel and Panarama -- in other words none. But, it seems to me from my years of busting knuckles and screwing things up on my DYIs and motor builds, that engines are really somewhat complicated version of simple things and thus the fixes are usually simple.

This is a long way of saying I would be very surprised if the sound and the low oil pressure were not related. Fix the oil pressure and you'll get enough pressure for the lifters and you'll be on your way, I bet. Of course, it's easy for me to bet, but there's no harm in fixing the pressure (in fact if there is harm it is in NOT fixing the pressure and cranking the thing).

Just my worthless opinion -- not even worth two cents.

But know we're all rooting for you!

I have some news... Good, not great.

Warmed up the car. Removed right chain housing heat shield and then right tensioner retention cap. Very little oil came out, about 1/2 oz, if that.

Imagine my relief/amazement/homer simpson moment when I found the tensioner UPSIDE DOWN! Doh! No little hole. Flipped it over, re-installed. Buttoned up the cap and re-installed heat shield.

Started up the car. Ran it for 15 minutes but the loud sound has remained. Hmm... Do we think running it could have damaged/collapsed the lifters?

Anyway, I looked under the car and there is a pool of oil. :banghead: Two steps forward, one step back. It's coming from the cap. I guess one can not re-use the gasket. I have one on order.

One other note. I noticed some loctite 574 sort of hardened around the side oil holes in the cap. I can see now how easily that stuff can break off and enter the vehicle bloodstream. Next time the gasket is going on dry or with a VERY THIN LAYER of loctite. Lesson learned.

During your 15 minutes, did the oil pressure look good?

574 only hardens without air contact, so it would just be carried in the oil - which is why you do a quick oil change after startup.

Cheers,

Mike

Hey peter if you have isolated the noise to the area of the lifters then maybe that is the issue they are not "pumping up" as mine did not untill i drove it. Mike and expeciallly Steve you guys have done engine rebuilds and lifter replacements, did yours quite down while idling afterwards without driving? I know mine didnt even though i soaked them in oil overnight. I certainly dont want you to drive your car and damage it but that is what i did and it worked. When you did the top end work did you replace the oil pressure sender? my original one and a "new" replacement one didnt work properly both went to zero when i took my foot of the gas and the warning light came on everytime i stoped. My third sender seems to work fine.


good luck......maybe its overpriced Porsche mechanic time?

I have had a few cases of really late pressurization - one took a good 30 minutes of idling and some light driving. In that case, all we did was the lifters, so we knew that was the cause of the noise. Sometimes they just pressure right up, and I am not sure why there is a variance - I do the presoak and use the same procedure every time (like once installed I crank for a bit with the DME relay pulled to load the lifters even more).

In this case, it's not just the lifters that were replaced, so its a bit of risk to run it that long to pressurize, but it could just be that issue. However, at least one fault has been found so far, so its worth a bit more digging to confirm everything else is ok before its run in.

Cheers,

Mike

I agree with Mike's first question. How is the oil pressure now? Lifters may be pretty dry at this point and take a bit to pump up. The bummer is I had suggested this after your initial post and you have had to struggle with it for a week now. Your oil level was high in the crank for a bit so you may see some leaks at the case through bolts etc. If the rest of your oil flow is good the leaks may subside completely.

The 20w50 oil sounds very thick to me, I think you need to button up your leaks and drive it.

Better check the other tensioner first.

meh, for california, 20w-50 is fine. Its what I run year round btw.

I think he's done both at this point, one correct, the other not.

where is the big leak coming from?

Actually, the pressure sensor is original. The indicated oil pressure is the same as before. When I think back to pre-rebuild I recall the same type of readings I am getting now but memory plays tricks on you.

Oil pressure is the same as before. On cold start-up it goes up to 3 - 4 and as the oil warms it drops to one or below.

Yes, you were right about the tensioner. I think I delayed getting to it because I preceived the heat shield and overall access to be a real PITA. As it turned out it was relatively easy to do. Live and learn. So far, knock wood, the only oil leak has been from the cap itself.

On a side note I have to give Pelican Parts a big thumbs up.:thumbup: I ordered the gasket yesterday at 3:45PM and I had it in this morning's mail.

Peter,

It can take time to get the lifters full of oil, even when they have been "marinating" overnight in a pan.

You need 1 bar/per 1K RPM, when hot for oil pressure.

Regarding the 574; one of the biggest DIY errors I see is the excess use of that stuff apparently fearing oil leaks. Its very translucent when applied properly and difficult to see. Most people use FAR too much and it can migrate to places where it shouldn't be.

"Less is more" is the guiding principle for 574.

Yes, correct. Both are NOW oriented correctly. The leak is coming from the right chain housing retension cap. Probably because I re-used the gasket. I have a new one so this should be a non-issue.

Hi Steve.

The oil pressure when hot is about 1K at idle and higher when rpms increase so I should be OK there.

Regarding the lifters, in your experience how long does it usually take and at what rpms? I have not done the 2k rpm 20 minute break-in yet. Perhaps doing that would get them pumped up?

Yes. lesson learned on the 574!

Hope all is well in OR.

although 1 bar at 1000rpm (which is not what it idles at, right) is a guideline, I've never seen a 993 on 20w-50 oil that has so little oil pressure. Most have almost double that.

What did it have before the engine work?

IIRC, about the same.

hmm, have you verified with a mechanical gauge?

sorry if you said this already.

No, not yet. I don't have one.

they have super cheap ones at parts stores. all you need is a mechanical gauge and some line.

Shouldn't your oil pressure peg at cold start-up? Even at idle I would expect more than 1 bar at normal operating temps. This concerns me. I would try the $20 mechanical gauge and verify your engine's actual oil pressure as suggested by others. Perhaps there was a pre-existing problem such as with the relief valve (sorry I don't recall whether you check this already)

Anyone know what the thread is at the pressure sender for attaching a gauge?

It can take some time,...anywhere from a few minutes to several miles.

Now,.......here is a KEY consideration at this juncture: camshaft break-in is very very critical and MUST be done in the first 15 minutes immediately from initial startup. In other words, one starts the engine and immediately gets the RPM's to 2000-2500 for at least 15 minutes. In most cases, that gets them full of oil. :)

It can take some time,...anywhere from a few minutes to several miles.

Now,.......here is a KEY consideration at this juncture: camshaft break-in is very very critical and MUST be done in the first 15 minutes immediately from initial startup. In other words, one starts the engine and immediately gets the RPM's to 2000-2500 for at least 15 minutes. In most cases, that gets them full of oil. :) :)

The oil pressure situation is another issue and may be why they are slow getting pumped up. I would recommend removing and thoroughly cleaning the oil pressure relief piston & passageway in the event that a bit of 574 or other sealant found its way in there.

I would also confirm oil pressures with a mechanical gauge to cross-check the one in the car.

Good luck.

Hi Steve,

I think in this situation he has used the same cams and same rockers, and assuming that he tracked each rocker to its correct original position, why would there be concern about break-in between the rocker and camshaft?

**update: Did not remember he actually resurfaced the cams and rockers, then I totally agree, break-in is critical for longevity....

Cheers,

Mike

Why aren't the lobes of the cam polished and shiny?
Is is just the picture?

The Cams were reground and then heat-treated. The rockers were re-surfaced. The shiny appearance will return after some break-in time.

Cams reground. Rockers resurfaced.

Then I hope that you did put break-in lube on the surfaces, and ran it at higher rpm for the initial break-in to make sure the surfaces work into each other well - did you?

Pressure relief valve removed, inspected, cleaned. Everything appeared to be in good order. I did not find any obvious gunk in there. Re-installed.

Yes, I put assembly lube on all surfaces including rocker surfaces. But no, I did not do the 2000 RPM run in yet. If you'll recall I was so concerned about the noise/pressure/temperatue issues that I thought it best not to jump into this.

I will do this today and report back.

Ick. Very bad memories of Engine #1 returning...

Read the majority of the thread. Saw someone (Steve, I think) ask if the case was split and the answer was "no." Didn't see anything related from that point forward.

From waaaaaay out in left field, with consideration given for the aggregate of all details listed throughout the thread, have you (or those far more knowledgable than this writer) ruled out the possibility of a problem with the oil pump and/or layshaft?

-Mike

This procedure really MUST be done at first start-up otherwise cam and rocker life is seriously compromised.

No, this has not been ruled out. How did you test this to find out?

OK, I decided to try the 2K to 2.5K run for 15 minutes. Here's what happened:

Pressure after startup 5 bar. Temp slowly rises to 9:30. Pressure slowly drifts down to 2 bar. Same old loud noise. At the 10 minute mark the engine just shut down. Seems ominous. What would cause this?

I tried to restart and it just turns over without starting.
I'm thinking I need to tear it down and try to find out what is going on and if I can't figure it out I'll have to take it to a shop.
:banghead::banghead::banghead:

Peter, I am sorry to hear this, that does not sound good. The oil pressure should not be dropping, especially to 2 Bar at 2k+. Not sure why the car has died.

While the engine is in the car, do a quick compression test, it's pretty easy while the engine is in place. Yo can do that with the DME pulled so you can crank and see what you get. You can do a leakdown tool if you have the tool, with new valves it should be close to zero.

I would not run the engine until you get dig into this a bit more. I may require dropping the engine again, if not just for piece of mind.

Did you check the pressure valve on the engine btw? I have lost track of all the stuff you have checked, you might want to summarize it in a list, it might reveal something.

Cheers,

Mike

Mike, Thank you for your concern. It's appreciated.

There was one strange thing that happened this time around and also the last time after I fixed the upside down tensioner on the right side: The oil level gauge did not move at all, even after 9 on the temp gauge. On one or two of the previous runs at idle I checked the level via dip stick and it was at mid level.

Yes, I did check the pressure relief valve. Everything there was as it should be. Nothing broken. No debris. I was very careful to reassemble it properly per the manual. I did not check the safety valve (horizontal one.) One thing I have not done is check the pressure using a mech. gauge. The sender is original to the car and I know these fail often.

I actually did do a compression test a few days ago on 4-5-6 and got 150 on all cyl. The battery was weak, however, from all the testing and such. I charged it up and ran one c-test on cyl. 6 and the pressure was 160 psi but I'm not sure the battery was fully charged. I can certainly do this again, should I?

I have no problem dropping & tearing down the engine again. Maybe I should and do the bottom end, perhaps that is where the problem is (pump).

Yes, I will make a list of everything done and tested and post here.

A bit of a hint to save your battery when doing a compression test - remove one plug from each piston so there is no compression on the engine, and then test one piston at a time - that way the starter is just pumping one piston at a time. YOu have to take one plug per piston out anyways...

160 is low for a NA car, should be 190 - 220 depending on the gauge, etc.

I doubt if you "broke" the bottom end from doing just the heads - that would be a wild coincidence. However, we have seen things like a little cloth plug was left in the inlet hole, and when started, the cloth was sucked into the primary oil pump circuit, jammed the pump and broke the layshaft - but in your case you are getting oil pressure, it just seems to lower as the heat comes on.

You can just swap out the sender unit if you do not trust the oil pressure sender you have. I can send you down a used one that I know works, but it will take time at the border...

Cheers,

Mike

I have to mention this since a client of mine had some similar troubles when he went to re-install his engine,....

Perhaps,......just perhaps something fell into the oil tank and got stuck in a hose, thus starving the engine of oil. I would review all the small details about the engine extraction and installation just in case something happened.

I think we asked Peter to check the inlet and outlet oil hoses, but I think that ended up being an external inspection. I guess the only way to check internal blockages is to take it off the solid line at the engine (gush!) and see what happens, and perhaps run a scope into the tank. He will lose the tank of oil, but when doing a rebuild, you expect a few oil flushes anyways.

Peter, if you are going to start to drop the engine again, why don't you disconnect these lines and check for blockages first? if you pull the line off the intake of the engine (the one just below the small oil filter with the 13mm bolt holding it in), all the oil in the tank will drain out so be prepared - but it should drain FAST. You can also use a flashlight to make sure no blocks are in the inlet of the oil pump by visually inspecting the opening on the block.

Cheers,

Mike

Been following this saga. I'm afraid to say this sounds a lot like oil starvation. Sure hope I'm wrong.

HA! At this point draining oil out is a piece of cake. Before I proceed I have 2 questions.

1. When I cleaned out the pressure relief valve about 3+ quarts came out. Does that sound about right?

2. Regarding looking in the inlet w/ a flashlight do you mean the hole where oil normally comes out during a change? I.e., on the crankcase?

Yes, something is up here. My gut is telling me there is an oil blockage somewhere. I have thought long and hard about how that could have occurred. I had the Travis Saga in mind during the rebuild so I was mindful of rags, etc... but you never know.

Maybe something crawled inside and died! It has happened before.

Any debris in the oil when you changed/checked out the tensioner and pressure relief valve?

You also mentioned the oil level did not move this time. Maybe you can drain a bit of oil from the tank...and a bit from the engine...then compare the two. If they looks/smell/feel/taste different, then that would indicate an oil circulation.

Nope, not that inlet. There is a main feed line from the tank to the engine - the inlet is just below the small oil filter on the engine. You had to remove this to drop the engine. If you undo the 13mm bolt and pull out the metal tube, that will expose the main oil feed line to the engine. If you peer down that hole, you will see the oil pump gears for that side of the circuit. Use a flashlight, if you can see the bottom, that end is clear.

I have not removed the pressure relief with the engine in the car and the oil systems all hooked up and full. It does make sense thought that is quite a bit.

Cheers,

Mike

You mean they should be the same? Not sure how accurate or practical that test would be, but I hope the engine is getting some oil (which it sounds like given oil on the tensioners and pressure relief spring) or it would have siezed.

In the case I mentioned, a nut had somehow fallen into the tank when everything was re-installed and it was sucked into the oil pump inlet. Needless to say, it wasn't pretty since he'd driven the car for a few miles listening to some odd sounds.

I won't belabor the details here, but it wasn't cheap to repair. Thankfully, you've not driven the car.

You might find excess sealant in places that it shouldn't, all the way to FOD so given the lack of proper oil pressure and noise, I'd likely encourage you to take it apart, barring discovery of something obvious.

I meant to say "indicate an oil circulation problem".

And if there is an oil circulation issue from the engine into the tank, then after running for 10 min you should expect to see some slight differences in oil that is in teh engine and oil that is in the tank right?

ok, I see now.

No debris whatsoever at the relief valve. In fact I strained the oil through a fine sieve to see if I could detect anything. Nothing.

When I removed the right tensioner cap I did find a little dried/hard loctite 574 which I had used as a sealant for the gasket.

this is unfortunate, but imho, its gotta come back out.

All of our guesses are like pin the tail on the donkey with the donkey in another zip code.

sorry dude, at least the engine removal should go much quicker

Yes. Agreed. I'm gonna disconnect the oil line first per Mike's suggestion, take one last look around and then drop it.

And, as this will be my third engine drop it should go quickly.:burnout:

Why exactly does the engine have to come out? You verified with an external gauge that it really does have low oil pressure?

I can't wait to Quote Vorsicht saying this:

Read this thread everyday wanting to see the above posted.

He has a noise that is not going anywhere, hes got what appears to be low compression, he's got an oil pressure problem (bad senders usually peg or don't work at all), and the engine shut off on him and won't restart.

Considering he's been working on this for the past week with the engine in and hasn't gotten very far, it seems like taking it back out and going over everything is a better idea.

Simply, really. I blew out the bottom end. Was sort of an "involuntary test."


Without (most of) the dry humor... some of the noises, oil pressure oddities and other head-scratching/eyebrow-raising items you described were very similar to those I experienced in the very short span of time and mileage after an oil change and before I spun a crescent bearing, sheered the IMS and turned the inside of my block into a Small Hadron Collider.

I haven't the slightest idea how to proactively test functionality without splitting the case and, while the probability of an identicle failure is near zero (I am aware of very few in the States; the running theory on most being that a foreign object was somehow sucked into the oil circulation system), mentioning it might provide another straw at which to grasp or lead to another idea which, hopefully, will lead to a solution.

(Edit: Mike beat me to it. Post #196.)

What did you end up doing? Was it repairable?

Let us pray to the Porsche gods!

^^^What Quad said.

You do not want to know. Lets not panic yet, just do the tests and get the wrenches out - and keep us posted for sure.

What is your current plan?

Cheers,

Mike

I found out. Yikes!

Current plan is to drop the engine and try to discover what's wrong. Here's a brief update:

1. Disconnected oil hose at small filter. 4.5 quarts came out and thankfully did not make a mess. Filtered, no debris.

2. Looked in the hole. Nothing obvious amiss. I can see what looks like 2 gears. Will try to get a pic tomorrow.

3. Removed other end of hose and confirmed no blockage inside.

4. Disconnected all top side stuff and some of the bottom stuff. Hopefully I'll have the engine out tomorrow.

Peter,

If you have access (beg or borrow) a filter cutter, I'd recommend opening both filters and laying out the paper media onto a clean sheet of butcher paper for a CLOSE inspection. Quite obviously, one never, ever uses a saw of any kind to do this. :)

Don't need a pic of the oil pump gears; that's what you are supposed to see. Sometimes I will swab that passageway for any little bits of 'smurf', however I think that time may have passed for that to be meaningful.

BTW, if you want to makes sure your layshaft is in one piece (which it is in your car since you did have oil pressure) you can rotate the crankshaft and see those little "gears" you can see on the oil intake rotate...

oil pressure
 

i was wondering could the suppply hose from the tank be colapsing when its gets hot.

Is quite stiff, so it would only do that if there is a blockage at the tank I would suspect so the pump suction would collapse the hose.

Didn't get much done today, had to do other stuff. Here's an update:

1. Drained oil from engine. Aprox. 1 quart came out.
2. Drained remaining oil from oil tank. Another quart came out here.
3. That brings the total to 6.5 quarts. Filters still in car.
4. Got a cheapo boroscope and inspected the following:

A. Oil in port (first photo)
B. Engine drain port (second photo)
C. Cylinders 5 & 6 (remaining photos)

The pistons themselves seem fine but how much oil should be on them (see pics). I believe we can rule out valves hitting pistons (at least on 5-6).

No. I inspected it and it is very stiff. No evidence of deformation.

Is that oil ON the piston? They should be very dry....

I would definitely take a close look at the filters not only for debris but for damage/defects. It seems to me that a defective/damaged hp filter could also cause a reduction in oil flow and pressure.

+993!! :)

Yes, that is oil ON the piston head. Where do we think this is coming from?

Since your bottom end was solid before you did the top end, I'd speculate that it's a result of something wrong with your valvetrain. Perhaps a valve guide or seal displaced? Do you see this on multiple pistons?

Yes, I saw this on 5 & 6. Have not looked at other yet.

Please let us know what you find in 1-4.

I feel for you. At this point, it's probably time to pull it back apart.

Agreed. I'm in the midst of dropping it right now.

Hey Peter,

Good luck with the drop, and these kinds of issues are always so discouraging... But I hope you'll find it sooner rather than later.

Thank You! You are right, it can be discouraging. When the engine just plain out died my heart sank. However, I am trying to be positive and pro-active. Instead of Engine-From-Hell I'm trying to think CSI-Oakland, 993 edition.

Current Status: Engine out of car, teardown beginning.:burnout:

When I rebuilt my 95 993, I had to tear it down again to fix a post build oil leak. You can save yourself some time by not separating the cam housing from the heads. Just lift the cam housing out with the head still attached. Be careful that you don't disturb anything and that loctite 754. This step helps with the re-assembly.

Good luck with the tear down. We're all cheering for you here.

OK, Good idea! I won't separate unless I have to.

This thread long ago set a personal record for me in that I can't help checking back hoping for good news. The thread also exemplifies just what is so wonderful about RL....all these really smart guys with vast experience willing to share their knowledge and take the time to post.

Hi Axl

Can i ask you a question please, when you fixed your oil leak did you remove all three heads and the cam tower in one go? If so was it straightforward to get the cylinders back over the pistons?

Many thanks

Berni

1 - 4 are about the same as the other. A light splattering of oil. Could this be due to the rings not seating?

+993!

Possibly, and this could explain low compression, but not the hot running. And I'm not sure it would explain the noise unless the rings were installed incorrectly. Did you replace the rings?

Yes, Replaced rings.

Some pics from the teardown:

1. Oil drain plug.
2. Stuff coming off the top.
3. Check out this rat's nest.
4. Right camshaft.
5. Left camshaft.

Not liking what I see on that oil drain plug - way too may filings after a top end rebuild.

Did you get one of those oil filter openers?
Just for your own piece of mind you should tear into the oil filter and see what it reveals.

Hang in there - just look at it as a learning experience - if there was a mistake made in the rebuild, you wont forget it after this! :)

+ Your posts here are an inspiration for others to keep with it.

Oil filters not cut open yet (no tool). Was thinking about borrowing a pipe cutter. Would that work?

Hmmmm. If you have oil in your piston and cylinder, it would smoke when running right?

Yes, I removed the head and cam housing as line unit. Just undo the 12 cylinder barrel nuts. Don't touch the head nuts. Also rotate the engine straight up so you can lift the assembly out.

Reassembly is easy. Put the piston and rings in as normal. Then just lay the head/cam housing assembly on top. Then bolt down.

Provided it does not create metal fragments from the cut.

Ideally you want a tool that works in a similar manner to a can opener - does a can opener actually work?

Anyone ever tried one?

If there was enough oil to foul the plugs, could expailn why the engine shut down?

Hope your up and running soon.

Been following this. Praying for ya brother.

that is very unlikely

Let's go back to the drain plug, for a moment.

Are those, in fact, metal shavings or are the lighting conditions/camera/my monitor playing visual tricks?

-Mike

Yes, there there was metal on there. Here are a couple more pics. The particle size was very small, like grains of sand. You can see some on the paper.

Peter,

Longacre makes a real nifty filter cutter made expressly for this purpose. These do not leave any debris in the filter casing which is critical.

Once you get the filters opened up and the paper media all laid out, you can drag a magnet through them to see how much debris (ferrous) you get.

particles' bronze color reminds me of two internals, rod small bearings and valve guides. And since there is oil on top of cylinders, just thinking of the latter

Does the debris actually appear as shiny copper, or is it the photo? Wish I was closer,as I would give you a hand. Good luck with it.

Emerald

The appearance is silver to my eye like the large rod bearings (which were new with this rebuild.)

Filter Cutter ordered, I should have it tomorrow.

Hi Peter

I really hope that things are not as bad as they seem to look. I rebuilt my 993's top end last year and have for various reasons not had the chance to actually drive the car properly since. I am giving the car it's first proper outing tomorrow. My issues have been oil leak related. I really feel for you and am hoping for a good outcome.

Berni

Thank you! Good luck with your ride...

Can't offer any advice or help Peter, but watched this intently from post 1 and been rooting for you all the way.

Thanks! We'll get there..

Update: A Tale of Two Filters

Cut open the filters with the appropriate tool. Photos below. Just a couple of notes first. I will show this in several posts as there are a bunch of pictures.

1. The large filter has been in the car for the last 800 miles (pre-rebuild use).
2. The small filter is brand new (post rebuild use only).
3. On visual inspection the small filter had very little metal - a few tiny particles found.
4. On visual inspection the large filter had many specs the largest of which was about 1/8 inch long. There were thousands, most very tiny.
5. The large filter has what looks like little pieces of plastic - could this be loctite 574, something else? See pic 4.
6. I used two magnets: small filter magnet is 1/4 inch diameter. Large filter magnet is 1/2 inch diameter.

Continued from previous post.....

Page 3 continued....

Is this right???

The large filter is for oil coming back from the engine. If there is engine issue, it would be caught by this filter.

The smaller filter is for oil coming from the tank into the filter.

Those are large pieces, bigger than I would have expected, especially since all you need to wear in was cams, rockers and guides. I did not split the filter on my rebuild, but the oil I dumped had lots of particles in it, but non that were this large that I found. Maybe Steve or someone can comment.

Well, engine is out so you might as well dig in. How is the disassembly going?

Cheers,

Mike

Yup, and since he has picked up particles in the large filter, its stuff from the engine, not the tank.

Plus the large end bearings on the rods. What about the idea that this could have come from pre-rebuild? The large rod bearings were very worn down. Not sure if this could have played into this - 800 miles is not much.

I am down to the long block sitting on a furniture dolly, exhaust removed. Waiting to coordinate 3 people to help me lift it up on to engine stand. I tried w/ me and one other. Too heavy. I think I will continue on and remove/inspect the rockers, Cams, the Cam Tower/Head assembly as a unit. I find having it on a stand is soooo much easier though so I might wait.

Must of missed this, and pardon my memory - so you removed the rods, and then put them back on the crank with new bearings? Did you use ARP rod bolts, and I guess you could not use a stretch gauge so went with the burnish/torque method?

Its funny that the large rod bearings were very worn - how bad was it? (and again, pardon me for asking, there are other rebuilds happening in the background where I am answering via emails/PM's, and its easy to get confused). I would suspect that, even with wear (and no failures), it would add to the metal content of the oil but not the pieces you are seeing here.

Cheers,

Mike

Yes, lot's of info on here. Easy to get distracted. To answer, Yes. I sent the rods to Steve. He re-conditioned them and installed the new bearings plus he added ARP Rod bolts and used a stretch gauge.

I will have to go and take a picture of the old bearings. IIRC, they were less than 1/2 the depth of the new ones.

Here are a couple of pics. I also measured them and they are in the range of 1.4mm to 1.6mm thick. Does anyone know the depth of these when new?

Wait, how can you use a stretch gauge on installation without splitting the block, there is no room? You mean you measured the torque required for the right stretch while the rods were outside the block, and then on installation you used that torque? (just checking).

Did you do a clearance check on the rod bearings using Plastigauge ? (this is a bit controversial since it will pre-crush the bearings before installation - but its the standard way). What was the brand of bearings supplied?

The good thing is you, if you have to dig this deep, can remove the rods and reuse the Arp bolts - unlike the stock Porsche bolts.... the bad thing is if you need to go that deep ...

Cheers,

Mike

I did not use a stretch gauge at installation. Steve pre-installed the ARP bolts at his place using a stretch gauge. What I did during installation was lube and torque to ARP's spec.

Regarding plastigage... I was advised not to use it. Steve does not like plastigage. Instead, I measured the crankcase journals which were all near top of spec. Regarding the brand whatever Steve would usually supply, probably Glyco.

Okay, good. Like I said its controversial, but I think Steve is in the minority in this case. Ok it should not be a likely failure spot.

I am lucky to have a few large I beams in the shop (by large I mean 16"!) and I can use that to hoist the engine onto the stand using a trolley and chain block. Wow, impressive doing it manually!

Cheers,

Mike

I've been following but got lost recently. Were the old rod bearings severely worn? This would be unusual. If so was the cause determined? The crank was okay and measured with a mic and found to be on size? Did you verify the rod journal bearing clearance and if so, how was this done? Just trying to get the facts straight so all can make useful suggestions. :)

Matt, I already asked those questions and got answers - just read back a few posts. One thing is bothering me though - if I would have found high wear on rod mains, I would have considered splitting the case - lets see how it goes though, he is taking it apart now..

Cheers,

Mike

I may be way off base here, but I sense a tension on Mike J's part concerning Steve Weiner's input. Both of these guys give way beyond what we could ever expect of them to our little problems. After all, they make their living fixing the problems we have with our toys. Having had 911's since 1987, I see Steve Weiner as a giant in our community. Mike J is new, but he is a generous contributor, and I'm surprised he finds the time to make his many posts. What bothers me at the moment is that Mike J feels the need to snipe at Steve. These guys should be the ultimate allies. They seem to want the same thing, enlightened 911 ownership, they both have impeccable reputations. I really appreciate Mike J's contribution here, I don't like his suble sniping at Steve. Just my opinion.....I really love both guys.....Chris

FWIW, I don't see any sniping going on. People have different opinions on things and that is as it should be. Mike J has been absolutely great in helping me - THANK YOU MIKE! Plus, his website is a great help to many. Steve is also a fantastic contributor here along with countless others. It's all good...:rockon:

I didn't get that. Everyone is just trying to help troubleshoot.

We didn't hear back as to exactly how all of the measurements were done. However, it is a mute point now as they can be remeasured if the damage isn't severe. Re: high wear - yes, this is important to know before deciding on a course of action. Was there a pre-existing issue perhaps? Its a tough one as rebuilds are expensive and doing them twice would be quite a set back for most of us. Hopefully it turns out to be minor and reassembling and reinstalling will not seem like a big chore!

No tension, everyone has an option and I am just expressing mine. Lots of opinions on measuring vs Plastiguage, pre-crushing bearings, etc. Its gets a lot wilder over in Pelican on the engine rebuilding forum - it's all good. Anyways, I am sorry if I came across like I was sniping, that was not the intent.

As for me being "new", lets see, was on PorschePhiles, then PorscheFans, then PorscheList (which changed into rennlist) and Pelican, and on this forum and contributing steadily since 2001 (and practically none of my posts are in OT - its all technical), been taking 911 apart for decades - now I feel old! :icon107:

Cheers,
M
Mike

Totally agree! Are you also thinking that perhaps the rod bearings might be the source of the knocking sound?

This has been an interesting thread, and with much of my engine in pieces it does raise some concerns as I start the rebuild process.

I would be concerned at finding bearings that were between 1.4 and 1.6mm thick. Generally the tollerance we are looking for here is in the 100's if not 1000's of a mm. I have measured all of my rod bearings and they measure between 1.479 and 1.482mm. With 2 bearings at 1.4mm you are going to have massive clearance which could quite easily show up as knock. The only way to measure these is with a micrometer, a vernier caliper is not accurate enough for measuring clearances.

Measuring clearance with plastigauge is really the only option if you are not splitting the case, as it is impossible to put a micrometer in to measure the rod journal.

If the old rod bearings were as damaged as you say I would be concerned that there may be damage to the crank as well. How out of round were the rods?

As for the metal pieces, Is it possible you broke a ring on install? It could explain a bunch of things (Oil on Piston, Low compression etc)

Good Luck...

Can you shoot me some pics of the rod bearings? I'd like to see the inside surface of each one and it would helpful if I knew which cylinder was which.

The case needs to be split and EVERYTHING cleaned out very very thoroughly along with the oil tank, lines, thermostat, cooler, and all oil passages in the cam housings and case. The galley plugs should be removed and all passages scrubbed out and flushed.

The crankshaft also needs its oiling plugs removed and then ultrasonically cleaned.

I did a quickie measurement yesterday on the old rod bearings at multiple points along the arc. This was not a precision exercise. I was just responding to Mike's question.

I honestly don't know how 'worn' they were. I just recall getting them back from Steve, looking at the new one's and noticing a big difference.

The measurements on the bearings were the old ones. Back then there was no knock at all. The bearings in there now are new and there is a sound, but the sound is originating between the cam tower and the cylinders. I wouldn't call it a knock but that is subjective. There could be a broken ring - don't know yet.

My best guess now is there was not enough pressure to adequately pump up the lifters and that is where the noise is coming from.

Steve, I'll send you up pics of the rod bearing inside surface tomorrow. Unfortunately, I do not know which came from which cylinder as I stored them together in a bag and were headed to the recycling bin.

Agree totally on all the cleaning.

Update on Dis-assembly:

Got down to 1-2-3 cylinders today. Pics below. I did not find anything unusual other than confirming oil in combustion chamber. We can rule out oil seepage from the valve train (at least on this side). Both exhaust and intake valves were dry. The oil is getting past the rings perhaps because they have not seated. There was no obstruction on the oil pathway between case and chain housing. Chain housing interior looks normal.

The camshaft looks ok to my unexperienced eye. The only thing that COULD be off is the wear pattern. One side of each lobe seems a little shinier than the other. I really don't know if this is normal or not - take a look at the pics.

Pistons, cylinders are next to come off.

Was that oil on the piston there when you pulled the heads?

Steve, you asking to look at the old bearings or the new ones? Maybe it does not matter - both sets - he will need to check those bearings anyways.

Just curious to see if the rod journal measurement and bearing id were measured prior to assembly to verify clearance.

You can't measure rod bearings unless they are installed in the rods with bolts torqued up to spec. You need an inside mic. Alternately plastigaging them during assembly will verify acceptable clearances.

Excellent advice Steve.

I would suspect that the knock is from the lifters. However that still doesn't explain all the particles in the oil filter etc.

Cleaning is going to be a long process, but needs to be slow and very exacting.

Oil Lines can be cleaned with a wire fish and rag soaked in oil
Oil Cleaner to American Cooler ~$120 http://www.americancooler.us/
Case hot tanked, galley plugs and squirters cleaned - Ollies ~$300 http://www.olliesmachine.com/
Cam Towers Cleaned - Ollies ~$90
Oil Tank ultrasonic clean or wash/flush at lease 6 times (When I cleaned mine I poured out the cleaning solution through a coffee filter to check for particles. I had none in the any round of cleaning but I kept going, still found nothing though)
Thermostat can be taken apart (regulator etc)

Be careful removing the oil tank as the filler hose (Convoluted hose) is easy to break.

That's all that comes to mind for the moment.

Yes. I also boroscoped these prior to disassemby and saw the oil there.

Steven, Great information. Thanks. What cleaning solution did you use for oil tank?

I understand. Could you recommend a tool(s)/brand for measuring the crankshaft journals/bearings once I have them out? I'd like something accurate but easy to use for a newb like me.

I think the big issue for Pete is to find the source of the particles in the oil - once that is found, then he can assess if that caused the noise, or it was an independent issue.

The complete cleaning that Steve is talking requires splitting the case of course, and that will involve a lot more work and expense, but with those metal bits in the filter, you have to be careful not to have anymore in the oiling system.

Years ago, when I attended Bruces engine rebuilding class, there was a guy with a 964 who was on his second engine rebuild - the first one was from the PO because of a bearing failure (rod I think), it resulted in metal going into the oil system, the current owner bought the car, and the engine was failing shortly afterwards. the PO did not clean well, and the particles got into the engine, and now he was taking it all apart to fix it again - and cleaning all the lines/etc. Bruce at that time suggested he toss the oil cooler, its too hard to clean right... but technology has moved on since then.

Cheers,

Mike

If the crank is out, the shop that you will send the crank out to get cleaned can do that for you, they should have good tools. I did that, also used my own micrometer (you need a fairly big one given size of the crank), and then used Plastigauge on both the mains and rod bearings. If the measurements all line up, you are good to go.

Measuring accurately down to the accuracy required is actually a bit of an art form, especially using bore gauges, etc. It also depends a lot on the quality of the tools, temperatures, and picking the right spot to measure. That is why I also like, for amateurs like us, to use a shot and then Plastigague since its a last confirmation and its hard to screw up (possible but harder... ).

Of course, I assembled the rods onto the crankshaft before putting the case back together...... and also Plastiguaged those, and used a stretch gauge for the rod bolts since there was room.

Cheers,

Mike

Does anyone know of a shop like Ollies but in the bay area. Shipping these things can get expensive. Then again, the bay area is expensive and it might be better/cheaper to ship.

Yup, that's job one. Then I can move on.

Can someone recommend a technique to remove the lifters from the rocker arms? The last time I did this I found it is difficult to get them out without damaging them.

Peter, I feel for you on this one. New lifters are almost impossible to remove from the rockers without damaging the somewhat fragile head. You can try cleaning the oil off the top and grabbing them with a paper towel in the jaws of a set of grommet plliers (plastic pliers). Your going to end up replacing some if you think they need to be inspected. Make sure the plastic seal at the base is not left inside the lifters that is easy to miss. (even from the original replacements).

I just finished reading your thread. Good luck with the rebuild and keep up the positive attitude.

Thank You!

Strange sound from rebuilt engine SOURCE DISCOVERED
 

VIEW DISCRETION IS ADVISED!



I finally found out the cause of the noise and it aint pretty.

The connector rod nuts were colliding with the very bottom of the cylinder. This created some raised ridges inside the cylinder wall which then scaped along the piston skirt. This happened on all 6 cylinders although side 1-2-3 is worse.

After removing the pistons I found the I could move the rods in and out about 1/16 to 1/8 inch. Sadly, I knew this BEFORE I put the engine back in the car. I mistakenly believed this to be normal. The use of Plastigage would have prevented this. Needless to say I am now a member of camp Plastigage.

I discussed this with Steve W. and our current theory is the nuts were not torqued down enough due to a faulty/inexpensive torque wrench. I am sending the rods up to Steve for inspection.

I am continuing with disassembly and cleaning.

Wow Peter, Didn't expect this.

On a bright side I bet your Lifters and the like are in good working order.

Oh ****, ouch.

I'm confused though. 1/8th of play on the rods is obscene. Was that really just from rod bolts not quite tight enough?

what did you torque those to?

sorry to hear about the damage, but you may at least be able to save the cylinders.

Rod bolts torqued to 40 ft-lbs. And remember this is just a theory right now. The only other thing I can think of is the crankshaft is worn. Any other ideas?

Yes, the silver lining!

Peter,
That's painful, but at least you've made progress.

PM sent.


Andreas

Are the rod bolts directional?

I see some references with them threaded in from the crank side and other references showing them threaded in from the piston side.

"After removing the pistons I found the I could move the rods in and out about 1/16 to 1/8 inch."
"In and out" perpendicular to the rotation of the crankshaft?

Even if the rod nuts were finger tight, you wouldn't get 1/16" play. Did you not install rod bearings?

Honestly -- and please don't take this the wrong way -- you might want to have a professional do the reassembly. If you thought having that kind of rod play was normal, well....maybe have a professional do the job this time.

Yes, half the battle is knowing what you're dealing with.

Perhaps. There is a first time for everything. Rod bearings installed on rod by professional (Steve W.)

Here is a short video showing the amount of play.

See Video prior post.

Peter,

I'm really sorry you have all these issues. That slop on the rod big end is just crazy. Is the rod cap tight up against the top section of the rod when you move it like this?

Are you sure there are rod bearings installed????

The rod parts do not appear to be moving in the video which leads me to believe there are no rod bearings.

Wow. With that amount of play, I guess you can be lucky that the entire thing didn't simply grenade. :(


Andreas

See item 1: Rod bearings

x2!!!!

You probably have some serious crank damage now as well.

Hey Peter,

Really sorry to hear this, but at least you found it.

I doubt if its the torque setting, as was said before, even hand tight would be tight enough not to get that kind of play. Perhaps the nuts undid themselves? Are there any gaps between the end cap and the rod itself (they should be tight up even if the nut is hand tight).

Anyways, the feel of the rods on the crank should be like oiled-silk - very smooth and no up/down play, and perhaps a touch of side play.

have you removed the rods yet? Were the rods machined for oversized bearings and that was missed? (even then, that is a LOT of play you are showing). Where were the rod bearings sourced? (or what has been asked - are their rod bearings at all?). Not sure what was machined with the rods and end-caps, but often they will be re-bored with the ARP bolts to make sure they are perfectly round.

Ok, if you pull the rods, and you have not beaten up the crank, that still leaves the issue if you need a complete teardown to get all the metal out of the engine, and to check the crank for roundness. That is hard to check when the crank is still in the block. The crank is likely to be damaged, but its pretty tough too. The pistons also go very deep into the barrels but I think you have enough clearances there, but you need to double check.

All in all, take heart, you found the issue, now you need to figure out what's next, be methodical and go forward. Please lean on all of use, we have literally several lifetimes of engine experience on the forum, and we would help you on each step...


Best of luck!

Cheers,

Mike

It's interesting that this occurred almost identically on all six cylinders. If this was Peter's error, he was amazingly consistent in making it. Not joking or making fun here. Just seems amazingly consistent for "human error."

Sorry to see this....

Terry

Looking back at the original posts you said this sound was there from the very beginning leading me to believe the nuts did not come loose.

Another take-away from this is during and after assembly, BEFORE trying to start the motor, and with the plugs out, turn the engine over several times by hand. As Mike J said, everything should turn freely and feel very smooth - that technique would have caught this interference.

Sorry to see you having to go through this - hang in there, you will get it fixed and learn a lot at the same time.

Well, a fundamental mistake like using the wrong bearings, or missing bearings would be repeated on each one, right?

I think the fundamental mistake is not checking the play with Plastigauge, but realistically that kind of slop should have been noticed on the spot. That is just experience, i am sure Peter feels really bad right now, and its best just to caulk it up to experience.

Cheers,

Mike

as has been said, its just a big chunk of metal. nothing that can't be fixed.

I'm really confused about this rod situation. You don't seem like the type to forget bearings, so I'm wondering what in the blue hell causes that much play. As has been noted, even finger tight wouldn't give that much play.

^^^^^^ That's exactly what I'm wondering as well... Especially if the rod bearings were professionally mounted by Steve, that is so much play, I'm just at a loss.

I'm not sure anything could be said here that you aren't already thinking, hindsight truly is 20/20. Just know that I'm sure everyone here is still pulling for you, just be glad you finally found it!!!! (How disappointing would it have been to do a full break down, and not notice a thing?)

Keep at it Peter!

Back in the '80's, rebuilt the engine in my first car, a 1973 cutlass supreme. When the crank came back, my uncle and I did not notice the machine shop had turned the rod and crank journals down differently. I believe the crank was 10 thou, and the rods were 30 thou. We bought 10 thou over for everything. Going from the memory of a 17 year old) Assembled the motor, and when turning it over by hand, we could hear the clunk at the top and bottom of travel. He quickly figured what was up. Upon breakdown, we could see the shop had plainly stamped the journals correctly, we just overlooked them.

In this case would a large bearing gap keep the oil pressure low?

cept in this case we'd be dealing with clearance of 60 to 125 thousandths (1/16 to 1/8")

That much clearance would have a devastating effect on oil pressure.

Without rod bearings there would be approximately 3mm of play or just around 1/16th, which is just about the amount of play I can see in the Video.

Now as Mike has said, tear her down, and start cleaning. Everything is repairable, I can understand how you are feeling, you have had a great outlook throughout this whole process, keep it up and she will be back before you know it.

Was there any signs of contact between the piston and valves?, with this much play there could be potential of contact.

Double post.

So this wasn't just a top end rebuild then?
I didn't think anything serious of the oil pressure due to the fact it was stated as a top end job. Yeah rod/crank bearing tolerances play a major roll in oil pressure. I'm sorry to see this.

Vorsicht,
First off, BRAVO for tackling something like this yourself. :rockon: Someone smarter than I said "You learn more from failure than from success."

To illustrate, I just helped ZombiePorsche44 through a flawless R&R of belts, fan bearing, and alternator in an afternoon.....using my knowledge of my 3x alternator rebuild over 2 months due to my own error on install round 1. Application of the BFH and alternator removal are NOT compatible...who knew... Oh, not to mention snapping 2 new belts due to a rag left on the bumper that was sucked into the fan... :banghead: Oh, and I need another full rebuilt alternator, since the thing STILL isn't right.

You are not alone my friend.
^^^^THIS...is why I am here. Good people.

I think Peter sent out the rods to to Steve to be inspected, machined and fitted with ARP rod bolts (along with the heads, etc). The engine itself was not sent out, and the case was not split, so rod preparation would have been done by Steve, but the final fitting and "mounting" would have been done locally by Peter, which should have included a clearance check, and proper torquing. If you are using ARP bolts and the torque method, there is a burnishing procedure you need to go through, but Steve may have done that given he set the rod bolts using a stretch gauge.

Because of the debris in the the oil stream, I think the only option forward is to split the case and do a complete cleaning, otherwise there is a risk of other pieces of debris in the system somewhere than can ruin any number of components, including bearings, pumpt, etc. He will need to split the case anyways to get the crank checked and cleaned, and then build it up from there. Steve mentioned that as well previously. The good news is that it will be a complete rebuild which should last many years.

Again, Peter, take heart, we are all behind you!

Cheers,

Mike

Check the rod bolts' end from the video...The nuts rhyme and are not loose.
This video shows how these engines are tough. Whatever the reason, with such play in the rods, the engine ran and ran.
The rods being loose, the engine case got filled up with oil from the crankshaft.
Hopefully you have the bearings inside, and that the rods are wrong. Lets hope the crankshaft is fine.
The challenge is to remedy with the least cost.

George, you think with the particles in the filter, the case need to be split, and the entire oil system cleaned?

Cheers

Mike

I would clean it with baby cotton swabs if it was me, up to the oil cooler.
And my first worry would be to rebuild with the least cost since I do not have funds these days :icon501:

Just read through this, sorry to hear about the problems but glad you found out what the issue was and I wish you the best with getting all back together!

Peter I am glad you avoided the take it out and run it hard to pump up the lifters. That would have left you with a pile of metal. Sounds like the bearings may not be on the rods. I have an extra 993 crank that was machined/ magnaflux'd at Ollies if it turns out you need one.

I could just cry.

BTW, you have to split the case. If the rods were hitting the cylinders then it is likely the oil pump has been hit also. Clearance on the pump is really tight eg Carillo rods require machining of the pump itself. Bummer, but it absolutely could have been worse.

MEA CULPA! MEA CULPA! No. Bearings. MEA CULPA!

I offer this with tongue in cheek: Confiteor

Confiteor Deo omnipotenti, et vobis fratres, quia peccavi nimis cogitatione, verbo, opere et omissione: mea culpa, mea culpa, mea maxima culpa. Ideo precor beatam Mariam semper Virginem, omnes Angelos et Sanctos, et vos, fratres, orare pro me ad Dominum Deum nostrum.

Can you guess which one is me and which one is my 993? :)

Ugh. Well, we've all been there once you do enough of these, or any, engines. Can't say I can admit to this particular omission.

I knew a fella who did the same thing in a Ford marine diesel. Bloody thing already made so much noise that you couldn't hear anything odd, but he noted that the oil pressure was low for a rebuilt engine and that was the giveaway.

After a VERY thorough cleaning and a replacement of the rods & crank, everything turned out fine.

First thing...bravo to you for your endurance, patience, and attitude. Second...bravo to all the knowledgeable people on here that have helped you. Lastly...I'm thrilled you found the problem. I couldn't offer any useful knowledge, so I just stayed on the sidelines...but I've read every thread on these 23 pages and have been pulling for you the whole time...and trust me when I say...I have never before read a 23 page thread in my life!

Best of luck now with the repair...I'm still pulling for you!!

I hope y'all don't mind if I don't reply to each individual post/question from the last 12 hours or so. There are too many and I have work to do! I'll do a sum up here.

Thanks to all of you for your support and advice, PM's and phone calls. The car would be long gone if it wasn't for RL. I am committed (perhaps I should be committed :)) to fixing this. I am lucky in that the top end is relatively unscathed and the bottom did not implode. Here is the plan.

1. Disassemble bottom end and clean everything.
2. Have the crank inspected, cleaned, repaired.
3. Rod inspection/repair.
4. Repair/Replace P/C's.
5. Send out oil cooler for overhaul.
6. Other bottom end stuff - seals, gaskets, dare I say bearings?
7. Pumps? What to do here?
8. What am I missing?

Thanks. Maybe I will put all of this into my next book :)

A hug. *HUGS*

Good luck!

-mb

Good Plan, all that I would add.

Remove and clean Oil Tank, Thermostat
Clean all oil lines
Rest and drink _______ (Insert beverage of choice)
Clean, Clean, Clean, Clean - Case and cam housings are important, remove oil galley's, piston squirter's and cam spray bar. This can be does yourself or outsourced. I would personally out source as for the price it is not worth the hassle (especially the squirter's)

Oil pump can be taken apart and cleaned and inspected. The tolerances/clearance in the pumps are very exacting and any damage would require a replacement. Most will recommend a replacement pump.

Oh one other thing.

As the cams and rockers may not have fully bedded in, I would speak to Steve W on his recommendation. They may need to be re hardened and then run in again, not sure.

Good luck Peter, we are all here to help.

Like trophy said, clean, clean, clean. Take apart the cam housing and clean or reverse flow the oil spray plugs. Debris can collect there, clog the oil spray, and kill your engine again.

Virtual Bearings


Peter,
Glad you found the issue. Pics coming later today.


Andreas

Hi Peter,

Admitting that the rod bearings were missed is, to quote the LOTR, "you have shown your quality, sir - the very highest".

For some reason, I found cleaning the cam carrier/spray bars/etc a pain in the butt - would send that out if you have a good local shop.

Definitely send the crank out, get it all checked/cleaned/polished if needed, and you can now do the rods and crank at the same time. Get a stretch gauge (the ARP one is not expensive) so you can do the rod bolts exactly right, or if you are not sure of yourself now, get it done. You rods will need to be machined at the best case, but hopefully not ruined.

if you split the case, you should replace the bearing sets (mains, nose, layshaft). You will need a gasket and bearing set for the bottom end - would recommend using Wrightwood racing gaskets, they are superior.

I am sure you do this, but i would explore the Pelican parts engine rebuilding forum, lots of good info and more people are not talking about the 993 and newer engines.

I would get (if you do not have it already) a 20 gallon parts washer and fresh solvent, it will be really useful to flush out all the passages, parts, etc.

When wiping bearings/parts, I used wipes designed for the computer chip industry - no lint since they are designed for wiping wafers - I used isopropyl alcohol first to clean, then break-in paste, and assemble.

You will need an assistant when assembling the block, its much easier to have to to torque the through bolts in the 20 min you have to do all of them - is a rush!

You may want to start an engine rebuilding thread(s) like I did with lots of pictures - that would be like having a bunch of eyes to double check the work.

Cheers

Mike

Thank You
Return Hugs *HUGS*

Hi Peter,

I know it's painful, but I would be curious to see how the rod and crank surfaces look -> you taking pictures?

Cheers,

Mike

Glad you figured it out Peter. Good thing you didn't take the advice given to drive it around!

I really have to say you have taken all of this so well (publicly anyway). I would not be so calm.

Keep up the good work. You will be a 993 engine expert here shortly.

having had the experience of losing three race engines, i feel for you. there is nothing like the feeling of "how much is this going to cost"? i recently converted a 3.6 1996 engine to a racing 3.8 liter. the engine had about 75k on it and was in perfect running order when disassembled. you can have the matching rods, cylinders, and pistons for $350 + shipping if interested. i have been in your place before and been nervous about "reconditioned" rods especially.

doug

Wow, that is a stinking good deal and very nice offer! Great stuff Doug!

Yes, On my list.

Yes, I would not have made it too far. I could have wheel-barrowed it out of the street and back home!

I agree, WOW. That is generous. I may take you up on it. They would certainly be in better condition than the current set up.

Mike, All good ideas. I will probably do a 'rebuild' thread. I love the idea of a parts washer but am limited on space at the moment.

A 20 gal parts washer sits on a bench, is about 20" x 24", and has a hinged lid. Without it, you are going to struggle with cleaning - and it's only around $120 or so. Buy one, use it, and then sell it on craigslist when you are done.. :-)

OK. I will re-consider. I was thinking of the box on a stand thing. All of these one-off tools drive me nuts and they accumulate like dust. I am focusing on the must haves. The nice to haves may wait.

Here are the pics of the rods. This is representative of all six although this is Cyl. 1, the worst. You will see the point of collision/rough area is nearest to the cylinder, or 9 o'clock on 1-2-3 and 3 o'clock on 4-5-6. They feel smooth to the touch.

oof. did you get an idea of what the crank looks like?

And just for fun, here is what it looks like without the Virtual Bearing.

It is not out yet but when it is I will throw up some pix.

peter

i got your pm, but dont know if you received my response. pm me your email so i can send you photos

doug

Hi Peter

I really feel for you on this. I rebuilt my top end with my brother and a couple of times we would have done something silly if had not been for the other set of eyes. When you finally win victory will be all the more sweet.

Berni

Doug, I PM'd you again, this time with email address.