Alingnment alters

[vic008]

VP2003 shaft drive. Had a mechanic do it, and I pulled apart 3mths later, and removing the coupler bolts was a struggle (ie when aligned those bolts will just slide in) So I aligned again, bolts engage freely, then I take apart yesterday, and bolts very hard to withdraw. Conclusion then, alingnment is altering. Engine is moving? Mechanic mate says it will, due to rubber mounts.

 

[Thistle]

Boat in or out of the water?

 

[vic008]

In water.

 

[greeny]

I've never had one move so much that it affects the bolts being removed. I guess it would depend on the clearance of the bolts in the coupling holes how much it's got to move before they interfere and stick. May be they are a very tight fit anyway and that wouldn't help if there was movement.
My first check would be the engine mount to engine bearer tie down bolts to see if they're moving.

 

[Stemar]

If the mounts are new or at the end of their lives. they will move, but I didn't need to touch mine for years once they'd settled in until one nut worked its way loose after several years. Maybe a bit of Loctite on the threads?