88 250 cc engine compartment

[Roy C]

On my 250 cc engine compartment I notice there a 1/2" plywood separating the engine from the aluminum
gas tank is rotting at the top I could remove pieces with my hand . also on both sides of the engine the flat surface feels soft. on one small section I pressed and feel balsa underneath the rotted plywood does anyone know the layers and if I can replace the rotten wood the hull is sound no other issues thanks roy

 

[JVM225]

There is a company named Alloy Metal Works in East Farmingdale that makes new aluminum tanks. You can bring them your old tank and they can make you a new one if you need it.
I'm not familiar with your boat, but it sounds like you're describing rotten plywood around your tank.
Sometimes they use wood to brace in a gas tank to keep it from moving around, and it usually has no structural value other than to keep the tank in place. If that's the case, you should be able to just take out the old wet rotten stuff, and replace it.
Is it an I/O? If so, you may have to remove the motor to get to the tank.

 

[Roy C]

Thanks no I was worried about the plywood upright piece separating the tank from the engine that has a few pieces of rot
and there's a ledge about a foot or so above the stringers on both sides of the engine that seem to have a weak spot
thanks again

 

[boatman37]

i know the piece you are talking about but can't help you with your situation. i believe that is all 1/2" plywood and the boxes beside your engine should be foam filled. my guess is if the wood is soft then the foam is likely soaked. sorry i can't help with the construction or remedy though. i'm not sure if the stringers run all the way to the aft cabin with the bulkheads built in between in pieces of if the bulkheads run the whole width and the stringers are pieced at the bulkheads?

i think there are a few here that have completely rebuilt similar boats but i think they were 268's or something but i would think the construction would be very similar

 

[Spudgunman]

i would find the source of the water leak and then decide if your up for the project, sounds like you need to rebuild the whole engine compartment at a minimum.

what size tank do you have the 100Gal? the engine needs to be removed to even move that tank, I have always wondered how I would do it with out cutting that wood out of my boat.

you may check the rear birth as well see if you have any rotten there, if you do I would almost say the boat is a loss or a total gut- and rebuild (horrible news)

 

[SCORPIO]

I did that same job on a previous boat, 82 260SXL. I replaced that bulkhead, the entire tank compartment and the side shelf. Removed all the wet foam and replaced with new closed cell foam and finished with a new gas tank. Took about two weeks of work to do but was well worth it. I epoxied in pvc tubing in the limber holes used to drain the water from the gas tank compartment. The factory just drilled holes in the plywood and let it bare, wicked up water over time and rotted. It's a DIY job if you are handy but it is MESSY and you will need to do fiberglass work. Use marine plywood if possible and epoxy resin, lower odor and stronger than polyester.

 

[Spudgunman]

What was the water intrusion point? Flooded bilge from rain water? Where did the water enter the fuel cell bulge area from - curious so I can protect or check my boat for this.

 

[SCORPIO]

On my old boat, they drained all the rain and wash water thru the floor compartments and int the bilge, no scuppers. So it was basically a design flaw. I reglassed the deck, removed the carpet and installed marine vinyl and sealed all floor compartments with hatches and installed scuppers.

 

[Spudgunman]

yes that is a problem, glad they put that into mine from factory!