Mercedes-Benz Forum banner

1 - 10 of 10 Posts

·
Registered
Joined
·
5 Posts
Discussion Starter #1
Hi guys,


I have a 1996 C200 M111 with about 126,000miles.

When I initially accelerate, the engine gives off a horrible chainsaw sounding rattle then returns to normal.
When I let off the accelerator pedal, it gives off the same chainsaw rattle for about 1-2 seconds then returns back to normal.

I know it’s not the belt tension shock as I’ve had that sound before as well and this rattle I have now is way more intense.
The sound appears to be coming from the engine block and not around the pulleys etc at the front.

I cannot figure out wh it is apart from a timing chain issue ?

The car is pretty tidy and I’m trying to look after it !

Any help would be appreciated !
 

·
Registered
w163 02 ML500 W210 97 E50Amg w202 99 C230K w124 - need more space, time to build again
Joined
·
2,189 Posts
Welcome bradjp, :)

Post a sound clip, we can listen to.
Pin pointing sound issues can be difficult.
 

·
Registered
Joined
·
5 Posts
Discussion Starter #3
Thank you !

Yea sure,

Here is the sound. It only happens on initial acceleration and when I release my foot off of the pedal.

 

·
Registered
w163 02 ML500 W210 97 E50Amg w202 99 C230K w124 - need more space, time to build again
Joined
·
2,189 Posts
Listen more carefully and touch each of the components that are operating with the fan belt, touch with perhaps a long screw driver to feel for vibrations (USE CAUTION because of the fan belt and moving parts in the front)
- alternator / power steering pump /water pump (any unusual vibrations could be the bearings)

Have you checked ALL fluid levels? - motor oil, PS fluid
 

·
Registered
w163 02 ML500 W210 97 E50Amg w202 99 C230K w124 - need more space, time to build again
Joined
·
2,189 Posts
With the water pump check, take the belt off and test by pulling the pump pulley front to back for movement, andyou can also run the motor for a sound test.
 

·
Registered
Joined
·
5 Posts
Discussion Starter #6
All fluids are good. Check them routinely.

Ok, cheers. Earlier today I went over the pulleys and removed the belt then run the engine etc and the sound has continued but I’ll go over them more carefully in the morning and see how I go for any unusual vibrations. I think I convinced myself it wasn’t coming from the front but I will double check. Could be wrong.

Thank you!
 

·
Registered
w163 02 ML500 W210 97 E50Amg w202 99 C230K w124 - need more space, time to build again
Joined
·
2,189 Posts
I do not think the "chainsaw" noise is coming from under the valve cover, but perhaps give it some love and add 1/2-2/3 bottle of seafoam top end cleaner thru the vacuum line attached to the brake booster (careful removing that vacuum line) and the rest into the gas tank. Your m111 will love you for it.
You'll need a patner to give it some gas to get the rpms up while it is poured into the vacuum line. You'll also get alot of white smoke out of the exhaust pipe, while you do this. (Warn your neighbours....) :)
 

·
Registered
Joined
·
5 Posts
Discussion Starter #8
Yea I’ve had my fingers crossed it isn’t something serious going on under the cover cause it’s quite sentimental now!
Thank you will be sure to give it a dose of sea foam and advise all neighbours beforehand 😂
 

·
Registered
'97 C200 Blue
Joined
·
81 Posts
I had a similar sound coming from my car about 18 months ago, thought it was the timing chain but turned out to be the water pump. Quite relieved as the repair was cheap, hate to think how much it would have been for the timing chain.Hope this helps.
 

·
Registered
Joined
·
5 Posts
Discussion Starter #10
I had a similar sound coming from my car about 18 months ago, thought it was the timing chain but turned out to be the water pump. Quite relieved as the repair was cheap, hate to think how much it would have been for the timing chain.Hope this helps.
Cheers glenn55, I’m going to try get at it this week when I get some free time and do some digging round. I do hope it’s something like the pump and not under the cover.
 
1 - 10 of 10 Posts
Top