OM606 vibration only when engine at running temp - PeachParts Mercedes-Benz Forum

benedict · #1 12-30-2011, 04:35 AM

Hi all,

Recently (say the last 5k miles) I've developed an annoying vibration which is felt through the steering wheel. It is only there when the car warms right up to about 80-90C.

Engine mounts were changed aroung 40k miles ago with OEM but to clear my mind of a possible failed mount I changed them again last night with genuine MB's. The vibration is still there. After a good feel around the car I found the vibration to be very noticable at the exhaust pipe (you can see it and hear it) and also when touching the engine, especially the belt damper area.

Whilst changing the mounts I took off the crossover pipe/black plastic engine cover for a look-see. I noticed that my breather pipes are a bit worped and not making a good seal (oil seaping from here) with the manifold and aslo noticed a small pool of diesel down inside the injector holes on two of the injectors.
Could either of these issues be related to engine vibration?

The engine sounds great with no knocking at all and pulls like a train at any temp except for this vibration.

Any other suggestions before I start throwing parts at it? Thanks

connerm · #2 12-30-2011, 06:23 AM

If you hear it when you're driving/accelerating, then probably the rubber bushings holding on the differential or the trans mount need to be replaced. You should also have a look at the flex plates to see if there are any problems. Also, look at the axle boots. If they're split and the grease is out, you may have a cv joint issue.

When you lift your car, do it safely with redundant safeties.

whunter · #3 12-30-2011, 06:42 AM

Quote:

Originally Posted by benedict

Hi all,

Recently (say the last 5k miles) I've developed an annoying vibration which is felt through the steering wheel. It is only there when the car warms right up to about 80-90C.

Engine mounts were changed aroung 40k miles ago with OEM but to clear my mind of a possible failed mount I changed them again last night with genuine MB's. The vibration is still there. After a good feel around the car I found the vibration to be very noticeable at the exhaust pipe (you can see it and hear it) and also when touching the engine, especially the belt damper area.

Whilst changing the mounts I took off the crossover pipe/black plastic engine cover for a look-see. I noticed that my breather pipes are a bit warped and not making a good seal (oil seeping from here) with the manifold and also noticed a small pool of diesel down inside the injector holes on two of the injectors.
Could either of these issues be related to engine vibration?

The engine sounds great with no knocking at all and pulls like a train at any temp except for this vibration.

Any other suggestions before I start throwing parts at it? Thanks

I need your VIN# to unlock EPC - WIS for a solid answer.

.

benedict · #4 12-30-2011, 06:51 AM

Quote:

Originally Posted by connerm

If you hear it when you're driving/accelerating, then probably the rubber bushings holding on the differential or the trans mount need to be replaced. You should also have a look at the flex plates to see if there are any problems. Also, look at the axle boots. If they're split and the grease is out, you may have a cv joint issue.

When you lift your car, do it safely with redundant safeties.

It only seems to be when at idle.

Yes, Safety was the first thing I took care of. It was only yesterday morning that I picked up a new set of 4wd ramps to do the engine mounts as mine were rusty and I just couldn't take the risk, I also had, under both sides 3 large blocks of train sleepers just incase, and had a manual (non fluid) jack under the engine and even then I was in and out as quickly as possible.

Sad news I read on the forum today about the young man who lost his life to a failing jack.

My w124 rolled off a jack stand a few months ago as I was jacking up the other side to place the second jack in position. Those plastic lift points really are a recipe for disaster. Still haven't used stands yet, just the ramps until I hear of a better/safer place to put them.

benedict · #5 12-30-2011, 06:59 AM

Quote:

Originally Posted by whunter

I need your VIN# to unlock EPC - WIS for a solid answer.

.

Hi Phil,

Sent PM with VIN.

whunter · #6 12-30-2011, 07:59 AM

Quote:

Originally Posted by benedict

Hi Phil,

Sent PM with VIN.

This is Roy.

FYI:
Delivery date 14 - 09 - 1993
Engine#: 606910 22 001543
Transmission#: 722435 03 394712

Researching further data now.

.

whunter · #7 12-30-2011, 08:12 AM

The accessory belt tensioner shock absorber has been superseded to MB# 6042000214, and makes a nasty racket/vibration when it fails.
SPECIAL ORDER SIP Belt Tensioner Shock,6042000214 - PeachParts

.

whunter · #8 12-30-2011, 08:52 AM

To buy these parts, contact
SALES SUPPORT
Phil Reinhardt
(888) 333-4642 or (208) 615-4005
philip@peachparts.com
Mon-Fri 10:00a-7:00p Eastern Standard Time

Engine Oil breather pipes

6060160630 pipe vent of cylinder head cover...
$ 5.75

6060160481 molded hose, elbow..
$ 7.50

6060160381 Molded hose, three way adapter..
$ 7.50

6060100170 Breather pipe..
$ 32.50

6060100270 Breather pipe..
$ 18.50

6060100370 Breather pipe..
$ 32.50

6060160430 Tube..
$ 9.75

6060160281 Molded hose, three way..
$ 4.40

6060160081 = (x6) Molded hose..
$ 4.40 each

6060160181 = (x3) Molded hose..
$ 7.50 each

6060160530 = (x3) Tube ..
$ 5.75 each

.

benedict · #9 12-30-2011, 05:34 PM

Roy,
Thanks for that info.

Understanding that the vibration damper is to take the stress out of the pulley system, do you think a bad vibration damper could cause the vibration to be passed through to the cabin/car?

And why would it increase only when the engine is warm?

whunter · #10 12-31-2011, 12:00 AM

Quote:

Originally Posted by benedict

Roy,
Thanks for that info.

Understanding that the vibration damper is to take the stress out of the pulley system, do you think a bad vibration damper could cause the vibration to be passed through to the cabin/car?

And why would it increase only when the engine is warm?

Yes, the noise is very penetrating.

.