schwank

Still trying to diagnose my no oil pressure issue in my new motor. But I want to back up and try to understand a 'special tool' that makes no sense to me.

So the oil cooler/filter housing is held to the block by 4 bolts. At least with the early motors, there is a sleeve inserted into the block as well to guide the OPRV. The early alignment tool is nothing but a simple metal rod that slides into the filter housing and that oprv sleeve. In theory this tool somehow aligns the housing so the oprv valve does not bind.

I simply don't understand how the tool actually does anything. The housing slides over that sleeve and is secured with the 4 bolts. What can actually ever go out of alignment? Is the tool only useful if that sleeve has been removed from the block?

Please educate me, because if there is a trick, I am missing it, and it just might be the reason I have no oil pressure. But the valve seems to move smoothly inside the sleeve with or without the tool already, so just trying to figure out what I am missing. FWIW, I am using a turbo filter housing with an external oil cooler, but the tool should function the same using an NA filter housing as well.

Here is the tool:


And here is a pic of my motor with the yellow arrow pointing to the oprv sleeve:

KuHL 951

The lower section of the alignment tool is stepped for the sleeve section. The larger one above it is for the housing. There's no magic involved but there is some slop if you just slap on the oil cooler housing that the tool adjusts for. Any chance that the sleeve isn't sealed at the base or loose at all? It does need to be sealed with a Loctite 638 or 648 if removed. Yummybud had this problem this year after losing OP. That sleeve can not have any movement at all.

Did you try reinstalling the PS pulley like Bruce said? I think you need to use it to get the right torque on the crank bolt.. The manual steering crank had a shorter snout.

Hopefully it's something simple like the PS pulley you left off.

Wipeout

So if I are reading correctly...

The tool doesn't align the OPRV as much as the oil cooler housing itself? If the cooler housing is out of alignment then the OPRV binds and you have no pressure?

KuHL 951

In a nut shell, yes, but oil pressure can be zero or too high depending where the piston binds. I'm still thinking Bruce from Arnnworx is right about the PS pulley...it takes up a gap that the crank bolt might need to torque down correctly. Maybe without the PS pulley the bolt bottoms out in the crank early and fools the torque wrench.

Wipeout

I'll let Eric verify, but from my conversation with him yesterday I believe he put the PS pulley back on with no change.

schwank

PS pulley was back on two nights ago with no change in results. At the same time I also used a borrowed early tool and disassembled and re-assembled the housing and OPRV. No change. Frankly the OPRV seems like it would move just fine in the sleeve. The sleeve was never removed from the block, it stayed put during machining. The tool goes in exactly as you descibe Steve.

I swear I have more than 150lbs of pressure on the crank bolt too. I am actually worried if I put a pipe extender on my breaker bar that I will snap the bolt or the crank.

KuHL 951

Damn Eric, you have done about everything I can think of. I've read so many 'failure to prime' posts on here I've lost count. Some of the weirder ones I recall were:
1. Someone used globs of assembly lube or Vaseline in the oil pump and it couldn't clear itself to prime;
2. The O-ring at the base of the pick-up tube was cockeyed and prevented suction;
3. A common problem was very small debris at the base of the sleeve that hung up the piston (this was my problem).

Was the block stoned flush with the girdle before installing the Loctite and oil pump?

F18Rep

Now this is Just an idea... What if .... we took an old pump drive sleave, welded some sort of attachment onto it so we could fit it into an electric drill. Then used the drill to manually spin the pump. Would it gall the crank? Would it suck in too much air around the sleave to prime?
Or, what would happen if we pulled the filter, closed it off and used the oil pressure test port to inject oil pressure (from an external pump)? Would it damage the OPRV seal?What if we remove the OPRV? Wouldn't it fill the pump and push the air out through the pick-up? ... Bruce

M758

eric,
have you started the motor or just cranked it? I have never had any luck getting a fresh motor to build pressure on cranking only. I just fire it up and it may take 5-10 seconds to build pressure first time then it goes fine.

Maybe the oil pump is just not turning fast enough on the starter motor to prime?

schwank

Well, Wipeout and I have spent another 4 hours on it today. The OPRV is not even getting oil to it. We took it out to check it out again (3 times), and coated it with Redline lube before re-installing. After probably 30 seconds of cranking with no results, we pulled the oprv again and the lube had not even been washed from the face of the piston. So I am definitely not getting pressure from the pump at all, much less to the cooler, filter and then pressure sensor. Supply line to the cooler is dry too. We even applied 30psi again to the dipstick and the case holds the pressure no problem... it does not bleed off until the hose is pulled from the dipstick.

The crank bolt has to be tight since we put an extension on and 18" breaker bar and he pushed and I pulled. A 2.5 foot bar with two guys push/pull should definitely equal 150lbs at least. I know the pump has oil in it as I backfilled it. Seems to be spinning pretty well as I have been charging the battery between tests, and the plugs and DME are pulled.

I pulled the pan off the old motor to check the pickup gasket against what I used. Tthe o ring looked far worse than the one I installed in the pickup on my new motor. The pickup in the new motor was hot tanked with everything else and I looked over it carefully before installing it. I honestly don't see anything I did wrong based on comparison to my other motor and Wipeout's old motor.

Seriously, we are baffled. The OPRV seems correct and slides pretty easily. We have tried multiple 3 piece OPRV's. We have torqued the crank bolt like 6 times. Joe what you say tempts me to try to fire it up but that also makes me very nervous as I know that the rotating parts are not getting oil yet.

I am extremely hesitant to tear it back apart yet but still don't have a better idea.

I am also super bummed because I am missing a race weekend as I type this... including 52 cars in my run group. Next weekend is Rose Cup, a SCCA national with a double 944 Cup race weekend. Life kinda sucks right now and I would love to get out there with my friends and race.

schwank

OK, back again. Still no love but possibly a path to pursue.

While talking today with a local lister Tom (StickShift) and looking at the car, we were discussing the oil pumps. The pump I put on my car was indeed from an early car, an 83 to be exact with a pre-83 stamping date on the pump. The motor I am installing on is a 86 block.

What Tom pointed out was this from the WSM: "Various modifications have been made on the oil pump and crankcase beginning with 1985/2 models. Consequently the new oil pump, part number 944 107 014 08, must not be installed in older engines."

Technically I have not violated this proviso. However, I am running a very early pump on a later block.

The part numbers in question:
83 pump (on 86 block): 944 107 104
87 pump (from orig 87 motor): 944 107 111

Sooooo... the million dollar question is: Does this mean I need to swap out the oil pump for a later one? We have confirmed the existing one is spinning, but I don't seem to see any oil coming out of the pump. Both of my pumps seem to have a later part number than the 'new' pump number listed for post 85.5 cars in the WSM. Not sure this makes sense, but... the current part for sale at Pelican (for $758!) is 944 107 014 11. Weirder, they list it for 07/84+ engines. Was that the '85.5' build date cutoff or what? They list 944-107-014-09 as the current part number for earlies up to 6/84.

Early: http://www.pelicanparts.com/cgi-bin/...F84)%2C%20Each

LAte: http://www.pelicanparts.com/cgi-bin/...-95)%2C%20Each

67rschev

Something to think about . I have read on an old thread in one of the NASA forums by Greg Forhdal , that the 83 model had a different oil pump drive thrust washer due to crank differences . This is the beveled washer that gets compressed against the oil pump drive gear by the crank bolt . In his post he had stated they were experimenting with coated rod bearings , and that they had a run a newly rebuilt motor for a while with the late thrust washer on an early crank , and it never built any oil pressure . The cause was the wrong thrust washer was used . If you use a 83 crank , you need the 83 washer . What is the year of the crank u are using ? 83 s had the nice factory crossdrilling .

Incidentally , the real gist of the thread was that the rod bearings suffered no damage with the coating .

Maybe your issue ?

schwank

I did call up to Fordahl this morning and though Greg was busy, I was told that the 83 pump will not work on the 86. So, my evenings will be nice and busy this week!

He can get me back by whipping me soundly at the Rose Cup races this weekend

StickShift

Let me know if you want a hand on this, I can help out a night or two this week. I can also bring a torque wrench so you can properly torque that bolt! Probably even get my hands on an engine hanger.

schwank

Thanks Tom! It was great to meet your friend Rod last night as well... much appreciated on the help and troubleshooting. And nice to see a 968 cab in person!

I'll let you know what is up... I plan to work on pulling the pump tonight and rebuilding the one off of my 87, since that is not too hard. I took tomorrow off work and hopefully will be able to get the bulk of the work done then. I would think the loctite 574 needs to cure a bit before I can turn it over.