craiger914

Hello, all

I am a little freaked out. Went for a little cruise and all of a sudden I noticed and developed a tapping noise from the motor. It's really prominent right around the 2000 rmp. The oil level and oil pressure seem ok and I'm 100% sure It's not the rockers clacking either. (I believe it's the driver side)
The motor only has 1600 miles on it! It's a 3.8LRS spec motor and does have mechanical lifters. I hope it's something I can tackle as I spent more money on this conversion that ever admit. The parts that went in this were supposed to have been top notch. MAHLE Motorsport 3.8L Pistons and Cylinders Pauter Rods, billet sport cams, Air Intake Boot Kit, Air Injection System Delete Kit, Ceramic coated Sport Headers with Polished Stainless Silencers, 16 quart Competition Oil Tank System.

Sorry for the long post, I'm just trying to give needed details for your much needed suggestions.

Thanks for your help.

I added a few pics too.

Steve Weiner-Rennsport Systems

Well sir,....from what little I see, your car is drop-dead gorgeous. Well done!!

As long as you have good oil pressure, I would begin the process with a stethoscope (or long-handled screwdriver) and place it along the valve covers and cam chain covers to localize the source and placement of the sound.

This will help you determine whether its valve train related or not.

I'm assuming that the valve adjustments are all perfect,...

craiger914

Steve:

Thank you for your response, I'll tell you I am about sick.
The motor is actually quite normal on a cold start. It's when it warms, then at low rmp, right around 2-2500. she starts her prominent tapping.
Yes. the valve adjustment is good. I've heard what you said, but I dont have a stethoscope and as far as the srewdriver... I'll assume the tapping will vibrate the srewdriver a tad more in the problem area? As far as I can tell, by ear, it's coming from the drivers side.

Should I take the upper and lower valve covers off to take a peak?

Monique

Just a tiny addition: the RS engine has hydraulic lifters.... unless you turned them to mechanical during the build.....

GL

And as Steve said.... DD gorgeous.

993Porsche

That engine is unbelievable. Andreas, would appreciate its super cleanliness.

Ken

AOW162435

I passed out when I saw those pics!

Have you spoken with the shop that built the motor?


Andreas

Martin S.

1. Take it back to the shop who built the motor,
2. If you want someone else to look at it, I'd recommend Kevin Kelly at Newport Auto in Newport Beach. He was the lead "wrench" at ANDIAL and has built may a high performance motor.

I also understood the 993 3.8 had hydraulic lifters.

I hope it is something simple...a 3.8 conversion must have cost a fortune.

JoeMag

Take the oil fitler off and cut it open.

craiger914

Thanks for you kind comments and responses.

Yes. The builder suggested and used mechanical lifters with the billet sport cams.

I haven't contacted the builder as of yet, they haven't been to easy for me to deal with in the past. It's a long story, but lets hope I can solve the problem myself.

Ok, since we are sure that mechanical lifters were used and we are sure that the noise only rears it's ugly head when the the engine warms what the possibilites are there?

If it were:

Valve adjustment: on cold start it's quite and normal. If it was an ajustment issue, they would be consistent or noisey all the time?

Timing chain: wouldn't that be a consistent noise as well?

Steve was kind enough to give me some direction order to locate the noise, but I believe I have a pretty good idea already. My question remains... what are the possibilites? or my next move?

Should I take both valve covers off and look for my answers?

clubsport1

Agree that 3.8RS normally has hydraulic lifters, many tuners seem to fit the mechanical lifters as fitted to the 993 cups when tuning the 3.8, so it's not that unusual.

MarkD

Beautiful car. Awesome powerplant.

There are too many possible sources to guess without hearing it.
I agree with your logic on cold vs. hot on lifters. mech. lifters would normally get quieter (if anything) when hot.

As Steve said, track down the source of the noise.
If it seems to be related to valve train, go in and look.

Timing chain tensioners are hydraulic (unless there was something else done in your engine) so that is still a possibility.
My .02c

I feel for ya... best of luck to you.

Flying Finn

You place the screwdriver in various parts of the engine and hold your ear against the handle of it. It "amplifies" the noise so it's easier to tell where the noise is coming from.

Good luck!

craiger914

Thanks,

I know I am asking a tough one without being able to listen to the problem "live"

I am going to take the MAHLE oil filter off and check for any metal debris before I attempt to start the car. I think I will take the drivers side (both upper and lower)
valve covers off as well to ensure the rockers are as they should be. I will take pictures of my progress and that might help with future suggestions or remedies.

Thank you all for your time, suggestions, and moreover patients.

I'm not a mechanic by trade... . but it can't hurt to investigate the matter.

Craig

craiger914

Hey guys,

Kind of a rough start, I'll tell ya.

Who in their right mind would tighten valve cover allen bolts to ? I had to resort to 1 foot pipe cheater bar set up! One was so tight I had to actually cut it off! They had tightened a few others the point they were bent when I finally got them out! I have pictures to follow....Per the book, torque is 7 foot pounds.

Crank case breather hose: They added some funky reducer to restrict oil existing the case. I'm not too sure about that? If too much oil is trapped in the case, that couldn't be good at all? If the oil wants to exit, shouldnt it be free to do so?

Oil Filter: Same frustrating deal, It was so tight I thought I would never get it off. I did, but I ended up having to vertually crush it before it cracked loose! Something so easy turned into a total hassel. My neighbor was kinda pokin fun at me ... not the best day for that...lol

Spark Plugs: Only had time to remove the uppers, look a little lean? maybe? a tad too much white?
I do run 100 octane racing fuel, though. I believe you still want a light brownish color..?
(not too white, but def not dark brown or black)

Rockers: so far so good, but I've just started.
I plan on adjusting all of them prior to starting the car. again. Could I be totally lucky and it be one bank?
Say a prayer.

Mahle oil filter: again, I had no choice but to finally resort to, big, channel locks to finally get it off. I tried three different oil wrenches and NOT one of them was going to cut the mustard.

Conclsuion: not much done, but no horrible findings as of yet.

** I read, today, about the Mahle filters and the check valves.
Seems as though some issues have come up in reference to the check valve sticking. Could this be a concern as well?

Some of the pics didn't turn out so well. I promise to get the settings correct next time.

Thanks

Craig

**The last pic came out the best and it has nothing to do with my issue... lol
That will be my next "FUN" project, can't be all negative.

Oh and I dded a few others.. interior w/911 dash, Recarro seats, and,hey quit looking at butt, rear end shot.

AOW162435

Your 914 - very nice!!

I presume this engine work cost a pretty penny - what does the shop have to say regarding your findings?


Andreas