Transom Rot

[gmc1962]

I have a 1989 Mirage Rampage 189 skiboat. We have owned it since new and it has never been moored in the water for more than a day. The boat is stored indoors and kept dry. I recently brought it out of moth balls for 5 years. Took it out, it ran great but I was getting water in the bilge. I put it back on the trailer and took it to the local shop to have the problem looked at. I was informed that the whole transom was rotten and the leak was between the outdrive (Mercruiser 5.7l alpha one) and the transom.

I am having a tough time beleiving that a boat that looks brand new and has been kept in dry storage could have this problem. The shop said that rot is like mold and can grow weither the boat is in the water or not. I know 21 years is quite a while but I spent alot of money storing this boat inside to prevent this type of problem.......

 

[BeaufortTJustice]

Re: Transom Rot

Once water gets into the wood core of the transom, it sits there for a very long time, no matter whether the boat is in or out of the water. The wood sucks it up like a sponge and holds it. Water + wood = mold and rot issues over time.

It's not the news you want to hear, but what you are being told is a very real possibility based on the above.

Good luck with your issue and let us know if you find out anything further.

After re-reading your post, I also wanted to add that "dry-rot" is also a possibility, but much more unlikely, and that could have led to the leak...interesting tautology here...which caused which.

To rule out dry rot, couple of things to consider...was the storage location a high-humidity location? Is there evidence of any other wood on/in your boat that is rotted?

 

[gmc1962]

Re: Transom Rot

Thanks for the response. There is a soft spot in the floor on the Port side of the motor. That has been there for years, it is just a storage area so I never worried about it. I kind of figuired it was just a bad peice of plywood. We live is Oregon, in the valley which is humid.

I noticed the bolts for the swim platform were sunk in on the inside on the transom. They only had 3/4" washers on them so I doubled up some SS fender washers at each location. That may also have been a sign of an issue back there I see now.

 

[ezmobee]

Re: Transom Rot

All it takes is an improperly sealed fastener or thru-hull to rot out a transom.

 

[gmc1962]

Re: Transom Rot

Thanks, I am looking into some possible resolutions. Any fix that I do will not have wood in the equation! We need to let anyone looking at buying a boat to be sure of the hull construction. I will report back as the plot thickens....