Transom Assembly

[maxse]

Last season we were seeing some water in the bilge after running the boat and in the off season they determined the culprit was the transom assembly so that was replaced.

They completed a sea trial last week without issues and I also took the boat out for an hour and she was running smooth.

Took her out again yesterday and on our way back we suddenly started to feel a strong ‘wobbling’ vibration. It occurs at all speeds and seems to increase with the more power I introduce. It becomes very obvious at 1750 RPM.

I want to think this has something to do with the assembly work and maybe a drive alignment issue? But, wouldn’t that be noticeable right after the work and not a few running hours later?

 

[Pirate Lady]

Prop? Just a guess. Good luck, my mechanic told me the most expensive repair can be chasing a vibration.

 

[Henry Boyd]

Replacing a transom assembly is a drive off & engine out project, so yes, the transom assembly replacement process is a good bet as the cause of the vibration/wobble/strange behavior. That said, I would not attempt to diagnose the cause, other than to tell your service people it’s not right.

Given the extent of the job, some delayed issues are bound to happen. Remember despite the time between the job being completed, there’s at most a couple of hours since a major repair.

 

[scoflaw]

Yup have the drive pulled and check alignment, U-joints and input shaft play.

 

[DWABoat]

I also would start at the alignment between engine and gimbal. Been involved with that process several times, if your mechanic was in a hurry or not careful, easy to be off. They will have to pull the drive and use the Merc alignment tool to check it.
Of course, it could also be a host of other things like mentioned above, but alignment is the logical starting point. Should be a “while-you-wait” and watch thing for a good mechanic.

 

[maxse]

Wouldn’t be surprised if they were in a rush…the way the mechanic shop is setup they can only get boats in/out to perform outdrive work +/- 2 hours of high tide and only have a few slips available for boats getting worked on.

May be time for a new mechanic. They left aft cabin window open after pulling the shrink wrap and a raccoon found his way in and wrecked my aft cabin.