If it is put on to the engine and gets on the belts will this damage them ? It was put all over the engine. Also what is a fair price for a shop to change one valve cover gasket ?

Thank you for any info

!986 420 SEL

Most engine degreasers are registered w/EPA & won't damage belts as long as care is used.
Shop labor for BOTH v/cover gaskets is around 1.5 hours, so for 1 side I guess would be .8 to 1.0 hrs.

Thank you for your reply!!! I also have a knock from the engine at all times and I would like to know how I can tell if it is from the lifters or from the camshaft ? Timing was checked and everything is fine with the chain and tensioner. Thank you for any info.

The only way to tell is by looking at the side at fault. It very well could be a bad rocker arm. (I have done dozens)

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Benzmac:
1981 280GE SWB
1987 16V
ASE CERTIFIED MASTER AUTO TECHNICIAN
SERVICE MANAGER FOR 14 BAY FACILITY
MERCEDES SPECIALIST 8 YRS
PARTNER IN MERCEDESSHOP.COM

If this knock is not looked into for another 4-6 months (money problems) and the car is still being driven normal what further damage can occur if it is a rocker arm, lifter, or worn camshaft ??? Timing chain and tensioner are fine. Thank you for any info.

If the rocker arm is the only part that is the problem now then replace it now. Waiting will allow the cam to wear out, if it's still good.

Re degreasers; Beware of the water-based butyl solvents as most are strongly alkaline in nature and will "frost" the aluminum valve covers found on diesels and many older MBs. If the engine is exceptionally greasy (as in valve cover leak) pre-soak with diesel fuel or kerosene, wait a few minutes then rinse with a hot water high pressure washer. Avoid spraying water directly at fuse box, elec relays and components, and be sure to rinse well! If an air chuck is available, blow all water out of crevices underhood.

Benzmac, The bad rocker you discussed here, would it give a knock that would be evident some time and not at other times?

If the rocker arm is worn out then the noise is constant. Intermittant noises are related to lifter pump-up.

Get a noise locator stheoscope and listen to the top of each valve cover approx above each spark plug. If it's audible while you are standing in front of the car, you should be able to pinpoint the source, or at least get it narrowed down a bit. I hope it's not a connecting rod or a piston slapping or a bad piston pin. You didn't mention much about the quality of the "knock", ie, is it high pitched or low, does it vary with rpm or load, can you hear it inside the car while driving??? How many miles on the car, how is the oil pressure? Lots of possibilities here..

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Jeff L
1987 300e
1989 300e

[This message has been edited by jeffsr (edited 01-28-2000).]