Transom edge moisture - - how to treat

[MartyTn]

My 1959 Glasspar Lido runabout transom has indications of moisture along the starboard edge and bottom. I’ve removed the cap, hardware and drain tube from the transom. The plywood is solid and dry down to within 4-5 inches from the bottom which is the lowest screw in the transom. The wood is moist at the drain tube area which is at the starboard edge, and so is not at the lowest point (center) of the transom. I’m looking for ideas on how to treat this moisture and possibly the plywood at those edges. The transom has been drying for a couple of weeks now with a fan. Lots of stress cracks along the starboard edge and starboard side of the bottom edge lead me to believe moisture in these areas need treatment, and possibly the plywood and/or bond in those areas may need repair. Another indication of need for treatment was the large buildup of brown sappy plywood glue residue on the hull from the drain tube. I’ve read about CPES, but I’m not sure if it can penetrate several inches of solid dry plywood to get to the moist wood. I’ve also heard about possible moisture displacement products but don’t know anything about these and if such a product would help the weakened plywood or bond even if the moisture was displaced. Any ideas greatly appreciated.<br /><br />Thanks,<br /> Marty

 

[quantumleap]

Re: Transom edge moisture - - how to treat

Sounds like it's time for a transom rebuild. But if you are trying to put that off for a while there are a couple of ways to approach your problem. First off, no product will solve your problem unless you get the wood completely, I repeat, completely dried out. If you can get it dry, a product like CPES applied thinned at first, and then full strength for the top coats, will seal it up as long as there is no rot. These types of products aren't meant to remove water and will only seal in any water not removed from core of ply. If there is rot, Antifreeze is a good method of keeping the rot from spreading, but replacement of the wood is the optimum treatment followed by finding and sealing source of leak(s).

 

[MartyTn]

Re: Transom edge moisture - - how to treat

Thanks Quantum; At first I also thought I needed a transom rebuild, but after getting into it, I just dont see the need for it. The transom is solid as a rock with no flex. Even the drain tube area is solid wood and not even soft wood, but it was just "moist to the touch". Not wet, just a feel of moisture. That was a couple of weeks ago before the fan drying began. Once dried, it can be sealed. If a product like CPES could get to the affected areas, I'd hope it should be okay since there's no flex now. I've avoided drilling into the center/lowest point of the transom so far, but I'd think that would be the place to see the "worst" of it, and also to let it drain and help it to dry, and then go from there...???

 

[Solittle]

Re: Transom edge moisture - - how to treat

Tap the inside of the transom with a hammer. The sound will tell you if you have rot & where it is.

 

[MartyTn]

Re: Transom edge moisture - - how to treat

Thanks SoLittle; I've done the tap test and all sounds good. I've seen/tapped rotten transoms, and "almost" rotten transoms before, and I know the difference in the sounds, etc. This one sounds good all over. I removed several screws from the transom including handles on both sides and speedometer bracket (4-5 inches from bottom) and a rubber engine cushion approx 12" wide that extended down the transom approx 12" mounted with 7 screws in the transom exterior, and every screw came out of solid dry wood. <br /><br />I believe that if there's any damage at all, it's only at the bottom and starbard edges. The sound is also solid there, but I'm not so sure that I'd hear any sound difference at those joint areas if there was a little "slight" damage - - like maybe just enough damage to weaken a joint bond but not rot yet???<br /><br />Still, I figure there must be a reason for the stress cracks on the starboard side and not the port side, so I figure there must be some damage there...??? <br /><br />Many thanks to all for ideas and opinions...