We just installed a 1995 AMG'd M104 engine and started it up.

Once the vaccuum cleaner sound of the air pump during a cold startup is gone, we noticed that as the engine got warmer, the valve assembly started to give-off a sound like a diesel's klattar-klattar.

I nor my MB tech remembers how an AMG'd M104/C36 engine sounds like, so we want to know if this sound is normal?

Thanks in advance,

:-) neil
1988 300TE w/AMG'd M104 engine, aka AMG C36

Valve train should not be that noisy. Even if they were solid lifters, which are noisy when cold and quiet down when at temp. Something is rotten in Demark. I has heard a few MBZ with the AMG treatment and even at full honk, I have never heard a noisy valve train.

__________________
Jeff Lawrence
1989 300e
2000 Dodge Grand Caravan SE
No matter what you fix, there will always be something else to fix..
"Warranty" is just another way of postponing the inevitable.

Do you have any history on the engine?

Engine has 18K miles, and was previously in a 1995 C36 that did F1 Medical car duty, and was retired (no accidents or blown motor issues).

Thanks,
:-) neil

I have seen where the lower oiler pin used in the front lower timing cover will work its way out and click against the front lower timing cover. This happened on Lee's C 36...We caught it while doing a reseal for an oil leak.

__________________
Benzmac:
Donnie Drummonds
ASE CERTIFIED MASTER AUTO TECHNICIAN
MERCEDES SPECIALIST 11 YRS

It's definitely coming from the valve train, and it isn't the typical lifter or rocker sound. Just a muted "klatta-klatta", but not nearly as loud or tinny as a diesel engine.

We think it's just because of the aggressive cam AMG engine's use.

:-) neil

I hope it's not pinging or spark knocking. The valve train should not be making noise such as you describe...unless..something is wrong.

__________________
Jeff Lawrence
1989 300e
2000 Dodge Grand Caravan SE
No matter what you fix, there will always be something else to fix..
"Warranty" is just another way of postponing the inevitable.

Definitely not pinging or knocking.

Another Mercedes list member just drove a C36, and found the valve train to be little noisy only at idle, just as I have.

Let's hope this is it.

:-) neil

This is a follow-up on the klatta-klatta noise that our C36 is making.
We've noticed that it only makes it during idle, and it sounds like its coming from the timing chain/cam sprocket area.

Via the diagnostic port, we can activate/de-activate the cam-advance solenoid.
When activated, the sound is gone.
When de-activated, the sound comes back.

Does the intake cam sprocket assembly get noisy, or could this be chain stretch?

Could this contribute to no high-end "umph"?

Our only testing is with the stock 300TE exhaust (single cat, single O2-sensor), so we are now fabricating a dual-cat and dual O2-sensor free-flow exhaust that will mimick the C36 exhaust system.

Any other ideas?

Thanks,

:-) neil
1988 300TE w/AMG'd M104 (aka, C36)

Excessive play in cam actuator linkage or chain tensioner has worn out, or chain has strecthed beyond adjustable limit. Don't wait for it to get worse.

__________________
Jeff Lawrence
1989 300e
2000 Dodge Grand Caravan SE
No matter what you fix, there will always be something else to fix..
"Warranty" is just another way of postponing the inevitable.

Another update.

Well, the klatta-klatta noise is still there. We re-installed the chain tensioner (it was too tight), and reset the timing chain (no stretch) and it's still there.

How does one diagnose that there is excessive play either in the chain tensioner or the cam actuator linkage?

Do you have to replace th entier cam actuator linkage?

Once the front top valve cover is removed, how can you determine if the lower oiler pin used in the front lower timing cover has worked its way out and is clicking against the front lower timing cover? Do you have to to pull the lower timing cover?

Anyone else have any ideas?

Thanks,
:-) neil