Motor Mount Replacement?

[kipwrite]

All,
Alas, the forward starboard motor mount under my Volvo TAMD31 has badly compressed...maybe an inch lower than the others. While the motor sits stable on mounts at all RPMs, I'm afraid the compressed mount has thrown the engine out of alignment, albeit modestly.
There's an automotive CV joint between the transmission and the prop shaft, which I suspect is bearing the strain. The cutlass bearing was recently replaced.
My yard quoted 70 hours of labor to a) remove the transmission; b) replace all four motor mounts; c) install an aquadrive.
There's excellent clearance under the oil sump for a small jack - and I'm wondering whether anyone has experience replacing motor mounts, and whether this is job that can be tackled by a) loosening all four mounts b) removing the CV joint and c) jacking the engine up by the sump (with a proper board as a brace) and then d) swapping out the defective rubber mount. I've run the boat for years with CV joint successfully and wondering what an aquadrive would provide that a CV joint would not, and whether this was a change worth making (I'm thinking of carrying a back up CV as a spare...)
Hate to part with that many $$ on a job that might be done more simply by myself...
Anyone dealt with this?

[merlin2375]

70 hours? Is that a typo?

[kipwrite]

Hard to believe, but not, that's not a typo..

[dhornsey]

I always thought that an aquadrive was a CV joint. Is there a difference?

[Rockter]

Do it yourself. If the CV joint has served you well over the years, then leave it.
Disconnect the final drive, jack up the motor, and change the mount.
It really is not a lot of work.
70 hours has to be, like, $5000.
Mounts are not too expensive. Perhaps it's best to change all four of them.
Keep diesel splashes away from them and they last a long time.

[negrini]

Not sure how old is yuor engine/mounts, but every mount has different stiffness based on engine weight, so better to change all at once. Hard work will be if you can't find exactly same size mounts. That took me days to re-bed the engine and mounts ....

[75R20]

Another thought is "why" is that mount compressed ~ 1" ? That's a lot. Bad mount? or ? I'd want to try to find out as I replaced the mount so it doesn't happen a second/third/fourth time. The mounts can't be cheap. I can't speak to the labor involved, but 70 hours is a bunch.

Kary
#49080