C&C-29 Yacht shaft vibration problem?

My father has a C%26amp;C-29 sailboat with a Yanmar inboard diesel engine. Last summer the prop shaft was damaged due to a collision and has since been replaced, but there's still a horrible vibration. He thinks the strut might also be damaged but is unable to get a new part or the proper measurements and angles to have one made. Can anyone out there help with this issue?

C%26amp;C-29 Yacht shaft vibration problem?
I will add one thing - DO NOT scrimp here...


You do not want an agonizing or returning problem.


Have a reputable mechanic in a reputable boat yard - do a complete allignment - and I would suggest a laser allignment.


If you have to replace the strut and cutlas - then you will have less money in your pocket AND less gray hairs on your head.





ONE MORE THING - I had to replace the bearings in the transmission due to a grounding. The Mechanic said he "would not garrantee his Laser Alignment if I did not replace the sloppy bearings".


Also make sure there is no zinc on your shaft and have your prop tested first.
Reply:Sounds to me it's a pilot bearing.
Reply:Check your cutlass bearing. Whatever the cause, it's going to be a yard repair. Have the boat pulled, and then you can do anything you need to, while it's on the hard. Make sure that if you run the engine to diagnose the problem, that you have a cooling water supply running to the engine. It could be something as simple as a bent or out of balance prop blade.
Reply:Sometimes the strut can be straighten, but it will need to be removed. Most prop repair shops can do this. Have a new bearing installed too.


Was the engine to shaft alignment checked and adjusted? I would have that checked first. Motor could have shifted if the impact was hard enough. You don't need to pull the boat.
Reply:definite alignment problem
Reply:It could be the strut.allignment. Check engine allignment and the cutlass bearing. The collision could easily have changed the allignment of the strut which would damage the cutlass bearing.

hollyhock