Seachest refit

[SeaSloth]

So the boat has a seachest to handle all raw water coming into the boat. It is fiberglass built into the hull and has 6 raw water lines going out of it (engine intake, heads, manual foot pump). There should be a picture attached.

The top appears to be plexiglass or lexan. The wingnuts are fairly corroded and the petcock is corroded to the point it is not usable. The outputs appear to be bronze and you can see by the green they are pretty old and have developed a strong patina.

I need to refurbish the box. I'm not sure I want to change out the bronze fittings but the top definitely needs work. I will at least change out the hoses and clamps attached to these fittings.

For the corroded studs that hold the wingnuts I was thinking of removing them from the fiberglass, using epoxy to fill the old holes and to hold the new studs in place.

For the top I'm not sure what to use. Any suggestions? I also am not sure what type of sealant to use between the chest and the top. I don't want something permanent because it is designed to be disassembled to remove any foreign matter that gets introduced. Maybe 4200 but that might be too strong. Any ideas about this or the plan overall. I've not done this before so I'm not sure what I need to watch out for.

Any wisdom is appreciated.

[steve77]

Making a new top of Lexan seems reasonable to me. You want it thick enough to be fairly rigid so it won't warp with time. Perhaps 3/8" is too thick, but that's where I'd start if it were my boat.

What seals the top of the sea chest now? I would think a gasket of 1/8" rubber would seal any imperfections in the sea chest lip. You can usually get sheet rubber at auto parts stores. They sell it as gasket material.

Cheers!

Steve

[rebel heart]

I'd do 4200 unless you use it for a watermaker's input. The possibility, at least in the beginning, of errant petrochemicals getting into the watermaker would scare me a bit.

I'd second the Lexan but just be careful and maybe buy a piece big enough to make a couple of them because with that many screw holes it would be easy to shatter it and get little cracks running through it.

I always liked the idea of a seachest, especially now that I have a watermaker and want to have non-aerated sea water as an input.

[SeaSloth]

Not sure what sealant is used now. It appears to be something squozen from a tube. According to the west marine advisor silicone is probably the best choice for lexan to fiberglass. I'm guessing that is what is on there now. I think some silicones are rated for below waterline use as well.

[SeaSloth]

Rh, I didnt think about the water maker. It does have one but I have no idea if it works or what condition it is in. I will likely use it if I can when I get to that point. I could use a pipe dope that is rated for potable water connection, I suppose. It really doesnt have to hold the lexan down, the wingnuts will do that. It just has to make the seal watertight.

[JPA Cate]

Sea Sloth:

A long time ago (in Internet terms) CF ran a fairly long thread about rehabilitating watermakers left pickled for a long time. When you're ready to approach that one, I suspect there will be folks here who will be able to point you in the right direction. Jim actually did it, but it was so long ago, neither of us remembers exactly what was done.

Ann