flex in transom

[Dilligaf]

checked out a seacraft looks solid everywhere but when i checked around the drain. there are 2 store/ cooler things on back of stern and the drains go out back of transom . well around one when i push on transom it flexes in.. is that rot? the drain is about 1 ft from corner of boat that should be pretty solid right??

[Dilligaf]

i know you have an opinion

[JohnB]

It's hard to say without seeing first hand, but most of these boats have wet transoms after 20 years, and at some point, they deteriate to mulch by about 25 years. My guess is if you hit it with a mallet there, it would sound hollow. You could alway drill a small inspection hole to see what is behind the glass. A moisture meter will tell you that it's wet.

[Dilligaf]

we tapped around on the hull and transom sounded good. all same tones even in the flexing area but the drain on the other side does not flex.also if you stick finger in drain port it has a little movement. if its flexing must be rot right???also i know rotten wood cant be good... and should be replaced but what can happen if not replaced??

[abl1111]

Yes - it's rot.

The drain tubes leading from the coolers leak and drip water into the transom. Over time, it rots the wood and things delam. The amount of damage is unknown till you pull it apart. However, the damage could be minimal too ?! That is a weak spot for sure - too much flex between the transom and the stern cap - the brass tube either cracks over time, or the sealant fails - either way, water gets where it shouldn't and you have problems.

When I re-did my transom, that is the area, both sides where the majority of water came from, and rotted the transom pretty good. I re-did the drainage tubes the same way - a dumb mistake on my behalf as they leaked within two years - but not into the transom ( besides I epoxied the transom thru-hole edges ).

I might remove those drainage tubes ( they're garboard tubes ) and replace with some sort of flexible tubing that can be epoxied in place - anyone have an idea what would work here ? Flexible is the operative word here. No matter what, the transom cap will have a little felx with the transom and that flex puts undo pressure on that drainage tube !

I bet a hell of a lot of transoms fail from this area !

[Dilligaf]

if there is rot in trans... what will happen? boat sink?

[JohnB]

You will get a lot of flex, and if you hop waves or trailer on rough roads, eventually, you will start to get cracks around the corners, and on the inside of the cut out of the motor. You will also start to see cracks in the splashwell too. The cracks are from the fiberglass flexing because the coring is disintgrating. Once the cracks start, you need to think about fixing it. If it hasn't had any patch/repairs, and is all original, it probably will be fine until the cracks show up.

The size/weight motor you have on it will also affect how fast it comes apart. If you slap a 500+ pound motor on something that was originally designed for 350, and the transom is weak, it will go even faster. Boats that were used if fresh water, or those that are left in the water for extended periods of time tend to fail faster.

IMHO, there are 2 types of "classic" SeaCrafts, those with rebuilt transoms, and those that need one. 25 years is a LONG time to ask a transom to last, especially with the newer/heavier/more powerful motors people are slapping on them.

[Dilligaf]

same goes for an i/o