Transom End Cap Replacement

[KAK]

I have a 1993 Starcraft SMF190 and I had to replace the transom wood. The pressure treated wood used for the transom ate the aluminum on both sides from the inside out. The job is near complete with the exception of replacing the thin aluminum capping that covers the wood and two aluminum skins that wrap it. Any ideas?

 

[danond]

Re: Transom End Cap Replacement

Got any pictures?

 

[Silver Heels]

Re: Transom End Cap Replacement

Hello,

I would be interested to see a picture of your transom as I am currently fixing a very similar boat as yours with the same problem. The Previous owner replaced the plywood with pressure treated. I noticed a scattering of small powdery corrosion spots, but just figured it was poor paint preperation from the factory. Then the spots grew bigger and I figured out why. with the old wood out, I took a small wire wheel on the inside and wire brushed the corroded metal out. The holes got much bigger once I busted through the powder and hit solid metal. My plan is to go over these spots with JB Weld then sand and paint the outside. How did you end up repairing the holes? To answer your question, my cap had some holes which I also fixed with JB Weld and painted. Looks great now. Depending of on how badly your cap is corroded, you might be able to do the same. If not, sounds like you may have to fab something up. Did you contact Starcraft? Keep us posted and get some pictures if possible.

 

[KAK]

Re: Transom End Cap Replacement

Hi. Thanks for your interest. I took my time to dismantle this transom. Plenty of screws, bolts, etc. I had to peel back the end caps in the corners to pull the old pressure treated transom out. Boy was it coated with white salt. The salt had eaten it's way through both aluminum panels that wraped the wood. I must have had 100 holes, some the size of a dime. I drill out the bad spots, scraped and wire brushed the sinner and outer surfaces. Then I washed them with white vinegar to clean the salt dust off the aluminum. Then I used West Marine fexible epoxy to coat the new marine plywood transom. I used two layers that were screwed and epoxied together and then covered in epoxy to ensure a good seal. I fiberglassed the entire transom and used a thickened epoxy to coat the inner walls of the aluminum. No inner surface was left uncovered. This way no cancer could continue. I am down to capping and installing the drains. I have a few pictures for you to look at.

 

[Landscaping Wiz 808]

Re: Transom End Cap Replacement

I wonder if this problem is only affecting Starcrafts. On my small 12' sea nymph I used pressure treated wood to replace the rotted engine pad. Uh Oh!
It might be time for me to remove them to see if I did any damage.

KAK - can you post those pictures so I (and probably others) know what to look for?

BOB

 

[slarn001]

Re: Transom End Cap Replacement

I was replacing my trailer bunks last week and my local marine supply told me the new chemicals in the pressure treated lumber react with the aluminum and cause severe corrosion. They actually lost two new boats to this problem.

 

[CATransplant]

Re: Transom End Cap Replacement

Don't use pressure-treated wood for aluminum boat transom boards. Plain ACX plywood is just fine, and will last for several years. I just paint them heavily with Rustoleum to seal them.

Thing is, you can replace them in a very short time, so it's no big deal.

As for the aluminum trim, I don't have a good solution.

EDIT: Belay that if you have a transom with wood sandwiched between two aluminum panels. In that case, you need to seal the wood in another way. I was thinking small tinnies with just transom boards.