installed new engine mounts but vibration is still there
 

Hello everybody,
My 1989 230E is not as smooth like some other W124s I have driven so far. The engine vibrates at idle (very visible) which passes to the cabin. At 900rpm I can even see the passenger seat shake and vibrate while I am at the driver's seat. I would say with the stereo volume at max a person would be able to tell if the engine is on or off. This is because the vibrations are so noticable.
Last week I have changed the engine mounts but that reduce the vibrations by about 10 percent. The mechanic looked at the transmition mount and told me that it is looking fine. Because the vibrations more noticable at the back seats he said it should be the bad mufflers of the exhaust system causing the vibrations.
I also noticed is that one of two rubber mounts of the air filter housing has come loose from engine. This is causing the air filter housing to vibrate at a very high rate.
Should I fix the transmition mount, the exhaust or the air filter housing mount and what else could it be?
How can I glue the rubber mount of the air cleaner housing back to the engine?

Hurshi

If the mounts are bad, I'd fix them all.

If you replaced the engine mounts, I don't see how that much vibration could be transmitted to the passenger compartment. Are you sure you used the correct ones - i.e. not those for the six?

Mine is a W102, and the first exhaust support is solidly bolted to the back of the transmission. The tranny mount supports very little weight - it is designed just to fix the location of that point, and provide vibration isolation - the mount is very soft. If it has hardened, exhaust vibration will couple in there.

I am more concerned that replacing the motor mounts did not substantially solve your problem.

Steve

I am going to fix the muffler tomorrow and will let you all know if it solves the problem.
Thanks for the info.

We had a C220 that had fresh motor mounts that vibrated and made some neat harmonics through the body. More noticable during the warmup cycle. The tranny mount solved it.



Joe

Thanks for your input. I will recheck the trans. mount too.
The muffler repair is postponed to next week. Iwill let you all know what solves the problem.
Thanks again.

Hurshi

problem solved for $120
 

I have found a problem part that was causing engine vibrations and howling sounds inside the car at low rpm accelerations. The bad part was a round metal part between the engine and the transmition used in both automatic and manual models. I don't know its name but in my language it is called mahovic. Can someone name this part for me please(picture attached below).
Here is a story how I found it was bad.
Yesterday, after a brief stop at my work I started the car, gave gas but car didn't go. Instead I heard a sound like some big thing
turning over while touching something.
Towed the car to the mechanic, he diagnosed it was a transmition clutch. After he took out the transmition and clutch we saw that a round very heavy metal part was torn into 2 parts and had cracks inside. At that moment I told myself I have to get rid of the car before it falls apart completely.
Today, my father bought that part used in other city for $120 and my mechanic installed it. A test drive showed no engine vibrations, the car accelerated smooth and felt very soft. I could push gas hard at low rpms but didn't hear a howling sound.
My mechanic told me that this part smoothes the torque coming from the engine and acts like a converter from the AC voltage to the DC voltage. It smoothes out the spikes at torque that happen
when spark plugs fire. This results in smooth acceleration and no engine vibrations at idle. That part in my car was probably already bad and later broke completely.
Below is the picture of the broken part.


Hurshi.

Hmmm....looks like a clutch? You have a manual tranny? Clutch replacement is a maintenance item, but roughness of engagement (or lack of-) are the usual symptoms of a problem.

Steve