knocking when releasing clutch

[Alpine]

I've a knocking when releasing clutch, and when coming on/off the accelerator, sounds like its coming from the engine area

I've changed the top engine mount a few weeks ago as it was split, but I'm wondering if it has exacerbated a problem elsewhere. The lower engine mount (under the car) looks ok, but are there another two somewhere? Could it be linked to the top mount, or something else?

[ITSv40]

If it is like the C70, there is a mount by the crank pulley, one on the front of the block under the inlet manifold, one on the rear of the block under the exhaust, the dog bone tie bar under the engine and the upper mount to fire wall.

[volvo again]

Definitely sounds like worn engine mounts, did you replace the bulkhead bush when you did the top mount?
The lower tie rod mount is also suspect but it may be worthwhile replacing them all, I did on my '98 V70 and it made quite a difference to noise/vibration

[Alpine]

Originally Posted by volvo again

Definitely sounds like worn engine mounts, did you replace the bulkhead bush when you did the top mount?

I didn't as it looked ok, but I'll have another look, and try to find the others

[SteveSarre]

Hi Alpine,

Often as one mount goes, that puts more strain on the other mounts, then they go too.

As far as I remember ...

I think the mount under the crank pulley would be the next suspect. Once it collapses or breaks then the two parts of the mount knock.

I am not sure how to test that, or to explain better, but I think you have to get down there and pry the engine up and down a bit and you may be able to see which bits of the mount are knocking. If I recall, there is some steel which stops the engine lifting up too far, or dropping too far. If the rubber block has become detached from its base plate, then the engine can lift too far and knock. If the rubber block has collapsed, then the engine can drop too far and knock.

If you are trying to fix on the cheap, and the mounting rubber block has become detached from the baseplate, you can take the mount off, clean up the base of the block with degreaser and a wire brush, then glue it back down with superglue! I have done that a couple of times and it worked fine. But obviously better to get a new mount.

HTH
Steve

[SteveSarre]

PS

Actually, I think the "the dog bone tie bar under the engine" (near the junction of engine and gearbox, going forwards to the subframe) is a good quick and easy one to check first.

Steve