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[dfloeter]

So this brings up a question. A few years ago I swapped our gearbox for the ZF12 and raised the engine accordingly.  The engine is now higher on the mount studs with more threads below than above.   I had wondered about the leverage on the mounts but opted to ignore that thought.   I suppose using the top end of the stud would and does allow excessive movement.  Maybe I should raise the mounts by shimming underneath.   So, should I?

[Ron Hill]

Ken & Kable : This is a real test of my memory about the old (replaced) M25XP engine.  I double nutted all of the top nuts on my K75.  As I recall (I have no pictures) there was still about a 1/2"' of threads above that top nut!?!

I'll guess that there is going to be plenty of threads.  If not I'd take 1/4" thick aluminum and make a shim the same footprint of Vetus mounts.

A few thoughts

[Ron Hill]

Dietrich : I'd leave the engine where it is as long as there isn't excessive vibration of the engine when running.

A thought

[KWKloeber]

So this brings up a question. A few years ago I swapped our gearbox for the ZF12 and raised the engine accordingly.  The engine is now higher on the mount studs with more threads below than above.   I had wondered about the leverage on the mounts but opted to ignore that thought.   I suppose using the top end of the stud would and does allow excessive movement.  Maybe I should raise the mounts by shimming underneath.   So, should I?

Dietrich

It depends where the engine/bell housing brackets land on the K75 stud.  See my previous post/warning.  Pics of yours??
**its best that the brackets sit in the lower half of the studs.**
 I saw a pic of a snapped off stud (apparently) where the engine torque was applied too high.  I cant recall if it was an M25 or XP and whether it was on a 30 or 34.

[KWKloeber]

@Kable

Here's some specs below that might help you.

If you measure where your engine brackets currently sit (or sat?) on the DF studs, w/ the new tranny they'll sit 8 mm above that spot on the K75 stud.
 
So depending where your brackets currently fall (fell?) on the stud (mid? above? below?) you can decide whether to shim and how much.

[dfloeter]

Thanks for the info.  It’ll be a few months before I get back on the boat but this looks like a great winter project.  Maybe even swap out the mounts while in there.  Happy cruising.