Plastic water tanks

[sirromcd]

I Have a Jeannea 43 Ds with blue plastic water tanks. One tank has developed a small hole in the bottom. Can this leak be fixed with fibre glass, plastic welding or any other method. The material the water tank is made of is similar to the material used in plastic kayaks seen all over the world.

In addition I want to convert one of my water tanks to hold diesel. Is there anything I should do apart from cleaning out the water and inserting new fittings?

[bottleinamessage]

I have a So 42.1 and the aft water tank cracked. I could find no way to seal the leak. Had a new tank fabricated (stainless) as a second fuel tank. Trying to use a water tank for fuel, IMHO, is not advised. You might consider removing the top of the water tank and dropping in a Vetus bladder??? Just a thought. The tank I replaced was the port aft tank. Not easy to fabricate and the estimates were very expensive as the hull slopes both to the rear and side. Luckily, the good lord entered the picture, and a friend enabled me to have the tank made is El Salvador by his father-in-law! Fit's like a glove and is a work of art.

[sailingdog]

Without knowing exactly what kind of plastic it is, it is hard to say whether it can be successfully repaired.

As for converting a water tank to diesel use...without knowing what the water tank is made of you'd be making a big mistake. If the tank is regular polyethylene, rather than cross-linked polyethylene, it will be likely to be damage by the fuel and leak. Also, many water tanks on a boat with multiple tanks are cross-plumbed, so water can be transfered from one to another. If that is the case here, you'd have to disconnect and plug those fittings as well. Finally, a diesel fuel tank needs a return line, and most water tanks don't have a fitting for it.

[Joesaila]

If you can find out exactly what it is and it really is the same used for kayacks, then it is weldable. The hot patch they make is indistiguishable. But don't guess. Either find out what its made of or send a piece to a pro who does that work.

[anchorsaweigh]

If I'm not mistaken (and I don't think I am) you are not permitted to have any openings, valves, taps, outlets, or any other intrusions in the sides or bottoms of fuel tanks. All fuel tank penetrations have to be on the top; the reason is obvious.

It certainly would make life easier if we could drain our fuel tanks from the bottom to clean them periodically.

Cheers,

Bob

[RandyonR3]

Anchor
I just checked to make sure as your post got me to thinking, The outlet on my fuel tank is on the side of the tank at the bottom. If I open the valve, the fuel runs down hill to the filter.