I am having a problem that I can't figure out. I hope someone knows what the problem is.

I have a 74 240D. About 6 months ago I was rear-ended (mild damage). About two days later the left motor mount broke. When the mount is broken, there is strong engine vibration.

I replaced the mount and everything seems fine.

The motor mount broke again in a few weeks driving. It has broken again and I have replaced it again two more times.

Does anyone have an idea what is causing this?

I tried loosening the fuel injector tube on each cylinder while it was running and found that each cylinder has the same effect.

Sounds like the engine isn't aligned with the subframe properly, possibly when you were hit the driveshaft pushed the engine out of alignment. Take a look close at the trans mounting & the subframe.

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Thank You for your reply.

I am trying to think of a method to determine any misalignment of the frame/subframe or engine mounts.

When I replaced the left motor mount theier did not seem to be any misalignment in the screw holes. I took this as a sign that the frame was not misaligned. maybe there is something else I should consider.

I did not replace the right motor mount or transmission mount. Thety don't seem to be broken but maybe a little stretchy. If this could be a contributing factor I will replace them next time around.

I am wondering if there may be any contributing issues relating to fuel injectior or that the cam gear seems a bit louder than I would like (but I'm not experienced with diesel engines).

Thanks Again

Jon Schmidt