Replacing engine mounts on an XJ12
 

Hello,

Under hard acceleraion, I get major vibrations. My mechanic says the engine mounts need replacement.

The thing is, he knows that I plan on doing a tune up, changing gaskets, bolting on some performance adders, doing a manual transmission conversion etc. He's making the case that we should pull the engine out and do everything at once. My wallet would rather not right now.

How big a job is changing the engine mounts? Can the engine be lifted enough (with minimal disassembly) to swap the mounts, or is it labor intensive enough to try to combine it with at least some of the other engine work I need?

If you've done this, or had it done, an hour or cost estimate would be appreciated.

Thanks,

ROD

Not an engine out job by any means.

Remove the air cleaners and the backings. Now you can actually SEE the mounts. I attack the RH side nuts first, as it will be easier by a fair long way.

Remove the top nuts on both side mounts, the LH will test your metal, as the power steer hoses are going to mess with whatever you try here.

I jack up the engine with a huge lump of softish wood under the front section of the "sandwich plate", and raise it CAREFULLY, watching for the fan hitting the shroud, and the oil cooler pipes/hoses, and any other stuff that wants to get in the way. It does NOT have to go up all that far, about 4" from memory. Common sense, and patience are mandatory here.

Once up, remove the other nuts and juggle the mounts out, that is fun, then juggle the new ones into place, more fun. Take note of any fibre discs that may in place, and ensure they go back where they were.

Lower the engine and secure it all, refit what you took off.

I would also be taking a serious look at the transmission mount, as most V12 noise comes that sucker.