Leaking Prop Strut

[nkihn1987]

Hoping for some advice on how to proceed.

Long story short, I purchased a 1977 custom built 28’ sailboat this spring. I had the boat hauled last week to investigate some vibration in the drivetrain. The mechanic advised that the cutlass bearing was shot and the motor mounts were “questionable”. Being that fall haul out is rapidly approaching, I had the cutlass bearing replaced and decided to have a second look at the mounts once on then hard for the winter.

After the boat was relaunched, I noticed seepage of water around what appears to be where the prop strut attaches to the hull (see photo). When I asked the mechanic about this, he sent the other attached photo of the exterior of the hull, indicating that he noticed cracks in the strut mounting prior to commencing his repair. It isn’t sitting right with me that I wasn’t informed of this as part of his estimate - Obviously a bearing replacement alone isn’t going to solve the issue if the strut is not bed properly!

My questions are as follows:

Is it possible that the mechanic caused this damage as part of removing the old cutlass bearing? Or more likely that the seller of the boat hid this damage with bottom paint? How to best handle the conversation with the mechanic?

Is it a poor decision to continue using the boat for the last month of the season at low RPM? Core damage, additional vibration etc? I covered the leaks in some epoxy putty until a decision has been made, although there is still some seepage. I am not doing any long distance voyaging, mostly off the dock pleasure cruises.

Best course of action to remedy in the off season and cost? I’m fairly handy - My thought was to grind out a bit, both inside and out, around the strut mount and fill with 5200/cover with epoxy. Then hire a (likely different) mechanic to potentially replace motor mounts and align the westerbeke.

Thank you for your help!

[Lepke]

Originally Posted by nkihn1987

Is it possible that the mechanic caused this damage as part of removing the old cutlass bearing? Or more likely that the seller of the boat hid this damage with bottom paint?

Looks like the strut/shaft hit something. I doubt the mechanic caused the problem. The bearing is usually removed with a puller that doesn't stress the strut.
I'd bet the owner covered it with bondo and paint.
It needs to be ground out so there's plenty of good hull to bond to. I'd use West Systems with 404 High Density Filler, never had it fail. But use what you like.

[Suijin]

I would give up on determining the cause. It could have been that way for years or it could have resulted from ham fisted removal of the bearing. I’ve seen a few yard workers over the years who’s solution to getting difficult bearings out is to go fetch a bigger hammer.

Ideally you want to pull the strut, grind out and repair the glass, then rebed the strut with 5200.

The challenge is getting the geometry and alignment right when you do that. You can only move the mounts so much and if the strut is not perfectly aligned when it goes back in you’re going to start chewing through cutless bearings.

I would also have the shaft checked for runout and potentially even replace it depending on what condition it’s in.