W124 driveline vibrations following engine mount swap.

[WDB124066]

Unless it is low compression or a faulty injector that doesn't behave itself till the car warms up. You never know for sure with these things?

 

[teddycatkin]

Thanks for the replies everyone. The gearbox mount has been changed too. The problem was not present before with my old mounts. Yes, the engine is sitting higher so a general change in alignment could be an issue. There is a mild drumming sensation too when driving at 50 -60 mph say.

Don't whether I should defend my indy or not but he offered to replace the rear diff mounts, diff seals, ABS sensor seal and reseal the back plate for £300 plus parts. The seals are only being done because the diff's coming out, not because they are leaking excessively. Please let me know if this is too much!

Wheel bearings ? will get warm after a few miles running and re-act differently from when cold as will diff oil ?

 

[kth286]

I think one important aspect of changing engine and gearbox mounts is to settle the mounts before the bolts are tightened.

The manual makes a point of this.

Just like many techs do not bother to lower car onto suspension before tightening newly installed suspension bushes (thus causing them to twist beyond their designed operating spec and shortening their life); perhaps the rear or front mounts were tightened up before the opposite end was replaced.

Mercedes make a point of saying the engine assemble should be moved/pushed several times on it's new mounts before the bolts are tightened.

The manual talks about the link of the exhaust assembly from the engine attachment point to the chassis attachment point needs to be in a de-stressed situation.