Transom leak

[GinnupsGirl]

On the port side, sea water is seeping from the transom into the boat. I have checked the exterior and there are no obvious signs of damage. Diver also looked underneath and found nothing.

I noticed the leak a week after filling water tanks. When water tanks were full, well over a gallon a day was entering the boat. Water tanks are now empty and about a cup per day is coming in.

Splash Zone was placed over the initial pinhole leak. Unfortunately water began seeping above it (upper black mark in pic) then eventually water penetrated the SZ.

Boat is scheduled to be hauled next week.

Has anyone else had a similar problem? Any suggestions?

[Glory]

I would take a good look at the water tank, to be sure.

[jmooney]

Doesn’t look like your problem, but I had water leak from a corroded trim tab screw that came completely through the transom, probably a replacement screw .

[cww]

Ordinarily I would say the rudder post stuffing boxes are the likely culprit, but in your case if the leak is directly related to how full your water tank is, then most likely you already have your answer.

[Captain Ralph]

Well,,, When the water tank is full, The trim tab cylinder is lower.
The tops of the tab cylinders, where they bolt thru the transom, should be looked at also.

Lots of ideas here.
It's a boat, always an adventure..

[Scarlett]

Check the bolts holding the swim platform brackets, I had one that was leaking.

[Captain Ralph]

Check the bolts holding the swim platform brackets, I had one that was leaking.

This is a great idea.

[GinnupsGirl]

Doesn’t look like your problem, but I had water leak from a corroded trim tab screw that came completely through the transom, probably a replacement screw .

Did the leak manifest near the corroded trim tab screw, on the bottom of the boat?

[jmooney]

Did the leak manifest near the corroded trim tab screw, on the bottom of the boat?

Yes it did, and very hard to find.

[GinnupsGirl]

The swim platform was removed by a PO and none of the repair areas appear to be leaking. Rudder post is also dry.

Leak location is near the port 'trim tab cylinders'. Perhaps water is seeping in somewhere around there. Earlier this week the port side trim tab came off the boat - screws holding it in place had disintegrated - perhaps these two issues are related.

Thank you all for your insight.

Rebecca