993RS

I have lifter noise now and then sporadically. Haven't had any noise in 2 months, and had it briefly this morning. This has been happening for about 18 months. Just sporadically. The moment the motor is warm, it stops.


On a German Porsche forum, someone said that it is not the lifters, but rather

"It's just the oil from from pump to hydraulic lifters draining away, the oil flows down and air then forms in the oil channel.
When the engine is started, a "certain amount of time" is needed until the air fills out in oil line , the oil arrives, and the stem is filled again.

So when noise occurs in the lifters it usually means that the oil channel from the pump is left empty, but not necessarily that the hydraulic lifters are defective."

My mechanic said I need a higher quality oil to insure a better flow of oil...

Steve, what do you think? Anybody else?

earossi

Interesting that your mechanic suggested better oil. I am assuming that you are running synthetic, right? If you are not, you should consider switching to it since most synthetics have superior additive packages in their formulations compared to dino oils.

You might also consider going up on the weight of oil. For year round driving, Porsche recommends 10W40 synthetics. Or, if you are just a warmer clime driver, you could run 15W50.

Addressing your symptoms, it sounds like one or more of your lifters are bleeding down overnight and that it is taking a few seconds for oil pressure to build up in them to eliminate the lifter noise. If that is the case, and the lifter noise quickly disappears once the oil pressure is established, I would forget about it.

When lifter noise becomes a constant all the time, then you probably do have a plugged or failed lifter and should think about changing out all the lifters since the others may be just as deteriorated.

Though I have never done it, the change out of the lifters is straight forward and appears to be something that can be done with the motor installed in the car. Someone else on the forum may want to chime in and suggest how difficult and costly it is to change out the lifters.

993RS

Thanks. The oil I use now is Castrol tws 10W 60.

LimeyBoy

I posted a similar issue very recently. Had a few replies including SteveW who all confirmed what earossi said above.

993RS

Weird is that it happens rarely. My car is a daily driver, so it is not a driving frequency issue...

Steve Weiner-Rennsport Systems

Hi Phil,

Indeed, the lifters are simply bleeding down and thats usually caused by either lifter seal failure or a thin oil at ambient temperatures. Its not uncommon when these engines accumulate some miles.

One cannot buy those proprietary seals (I've really tried that one) so we usually replace the lifters when these engines have some miles on them. You can try a 15w-40 or 15w-50 oil to see if that helps, however if your car has over 60K on it, I usually replace lifters to keep this from recurring.

This can be done with the engine in the car; you'll need to pull the valve covers and then rotate the engine so each rocker is resting on the heel of the camshaft so the valve spring isn't compressed. The rockers are removed and the lifter is easily replaced.

993RS

Thank you Steve. I have 90'000 miles... Guess sooner or later I'll have it done...

Hope you are recovering OK....

geolab

Salut, the oil you are using is one of the best for the 993, you should not have doubts.

Steve Weiner-Rennsport Systems

Hi Phil,

You are quite welcome,..

I think you are squarely in that window of needing lifters: I have found that once some begin making noise, they do not heal themselves and eventually, will require replacement.

I'm much better, thank you!

shadow993

How hard is it to replace your lifters on the Intake/upper heads? I think I have a bad lifter. I replaced the lower lifters last year.

Thanks in advance

Mr Swed

Just as Steve said "the lifters are simply bleeding down and that’s usually caused by either lifter seal failure" when I change my lifters 6 years ago the seals were so dry that they simply cracked just by touching them. It could be that the detergents in cheaper synthetic oils dry out the rubber in the seals.

Steve Weiner-Rennsport Systems

Heat is the culprit; that's what causes the seals (O-rings) to harden, crack, and fail which allows the lifter to lose its charge of oil.

Its a proprietary seal made just for Porsche and not available anywhere either here or in Europe, even after trying diligently for over 12 years.

Proker911

Thank Thank Thank you - I am new to the and you have saved me - I am a long time 993 owner and we have just developed the TICK TICK noise - so now I know what it is.
Please can anyone guide me through - in car access to changing lifters
torque settings for such things as rockers etc..
Removal of lifters do you need a special tool.
What happens if the old seal disintegrates in the hole?
Not had to do any work on the 993 other than services but not new to spanner work but know from other cars previous knowledge and access tricks make all the difference - PLEASE share the 993 love.

jan the man

Go here

http://pcarworkshop.com/index.php/99...er_Replacement

I did all mine two years ago with engine in car, if you strip certain lower allen head screws when removing the exhaust manifold must come off to get them out.

Not too bad if you are mechanically inclided and go slow

Steve Weiner-Rennsport Systems

For those who are mechanically inclined (& interested), look carefully at the Step 6 picture and note the uneven wear on the cam lobe.

See how the left side is polished and the right side almost looks untouched?? This is quite common now and indicative of QC issues with the rocker arms from the Factory. The pad on the rocker arm was not ground parallel with the rocker shaft bore and this manifests itself with excess cam lobe wear on one side or the other.

Brand new factory ones exhibit the very same problem and that's why we haven't bought new ones in years unless they are dished or cupped. Instead, we regrind them correctly to ensure even wear and pressure distribution across the face of the cams & rockers. The payoff is reduced wear and longer component life (providing the proper oil is used).

We do provide this service to other shops as well as individuals doing their own work.

Mike credited the illustrious John Dunkle for the great pics and I regret I didn't see this while he was undertaking this project since I would have been happy to help.