Need suggestions for hatch repair

[buckbuck]

The fuel tank hatch on my boat has developed a soft spot. I removed it and confirmed that there is an area where the Balsa wood has rotted. Does anyone have suggestions on how to proceed? Do I plan on removing the fiberglass underneath and replacing everything.? Not sure what to do here. Anyone remember others doing this?

 

[Scottintexas]

My clean out hatch rotted,

https://jetboaters.net/threads/clean-out-hatch-is-rotting-fixed.1227/

I'd suggest cutting it out from bottom and putting new wood in and fiberglass over it


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[Scottintexas]

Also

https://jetboaters.net/threads/2007-2009-230-clean-out-hatch-needed.20280/#post-345939

 

[zipper]

There was this rot repair on an older 04-06 Yamaha. But yours will be easier to get at due to the hatch being removable. Good info.

https://jetboaters.net/threads/2004-2006-230-floor-rot-repair.11861/#post-203691

 

[buckbuck]

Thanks guys. I just spent the last hour reading through what @CrankyGypsy accomplished. Yikes.
So @Scottintexas do you feel it would be best to cut out all the balsa and replace because you can't get all the wetness out before injecting the epoxy?
@swatski are you still recommending the pour in stuff? I think I will consider that if I can keep the white gel coat intact as a mold. Just pour it in and fill the entire thing sounds easiest.

 

[swatski]

Thanks guys. I just spent the last hour reading through what @CrankyGypsy accomplished. Yikes.
So @Scottintexas do you feel it would be best to cut out all the balsa and replace because you can't get all the wetness out before injecting the epoxy?
@swatski are you still recommending the pour in stuff? I think I will consider that if I can keep the white gel coat intact as a mold. Just pour it in and fill the entire thing sounds easiest.

Yes, that thing is the bomb. There are at least two formulations the last time I checked, both meant for transom rebuilds - pouring large volume of resin into a cast/mold - stronger than concrete and lighter than fiberglass, formulated to cure without generating excessive heat (when mixed and poured in large volumes) - so no worries about it cracking the gelcoat or skin or melting anything.
However, it helps to be able to pour it flowing down... so if need to pour inside/around a hole (through a circular cut) - I would want to "mock" the pour just to see what it would feel like. The cure time is few minutes so you want to make sure the stuff can stay inside while curing and does not flow out.
Also check the shipping costs, it's biohazard and could be a factor in total cost. Shelf life is limited like with any poly-resin so getting it from a reputable source (fresh) is important. I can find an address of people here in MO I dealt with if you need it, it;'s been a few years I last checked.

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[Scottintexas]

So @Scottintexas do you feel it would be best to cut out all the balsa and replace because you can't get all the wetness out before injecting the epoxy?

it wasn't so much the remaining wetness it was just the unknown factor of "did the mix get to all the voids" and the time (patience) it involved.

I knew (or thought) most of my rot was around the latch hole but I knew I had cracks around the edge, whether that was from rot or just weakness and continued stepping on the hatch from above,

If I had to do it again I'd cut out a section where I thought the rot was and continue outward until I found good wood and either replace the wood and glass over or as swatski said just pour it in (maybe you could mimic the hole with a piece of thin cardboard rounded to a circle)


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[buckbuck]

I need you guys to help me feel comfortable with this. After opening a corner of the hatch it appears the balsawood is rotting around the edges also. I am now leaning toward cutting the unfinished bottom of the hatch and removing all the balsa. This would leave a shallow (1/2") pan of gel coat and fiberglass backing. Does anyone have concerns about pouring 'CarbonBond transom compound' into the gelcoat shell? The temps are supposedly only going to get to 160 F. Would 1/2" of this stuff be able to support the weight of people?

 

[swatski]

I need you guys to help me feel comfortable with this. After opening a corner of the hatch it appears the balsawood is rotting around the edges also. I am now leaning toward cutting the unfinished bottom of the hatch and removing all the balsa. This would leave a shallow (1/2") pan of gel coat and fiberglass backing. Does anyone have concerns about pouring 'CarbonBond transom compound' into the gelcoat shell? The temps are supposedly only going to get to 160 F. Would 1/2" of this stuff be able to support the weight of people?
View attachment 111657

I'm pretty positive you would love the compound. There is basically zero risk of overheating damage, especially with such large surface to volume ratio as you will have there. There are less expensive ways to do this as it is all just flat and open but the compound will give superior strength and should be easy to do on a level surface. It is very light and probably the strongest of all the options. I put a sledge hammer to a puck-sized piece (a leftover pour) once, just out of curiosity, and I could not dent or brake it apart.

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