Pin hole leak in water tank

May 28, 2020
10
Hunter 36 Vision West Vancouver
My wife and I have just purchased a 1995 Hunter 36 Vision sail boat and are in the process of repairing the fresh water tank. The water tank is 75 gallons (sort of L shaped) and has a pin hole on the top corner of the seam where the L shape is. The tank is white and translucent. I have use JB weld in a tube and a JB in a putty to no avail. Does anyone know what the tank is made of? Does anyone have any tips on how to repair it?
 
Jan 11, 2014
11,401
Sabre 362 113 Fair Haven, NY
Probably polyethylene. Regular glues and epoxies won't stick. There was a recent thread here on repairing polyethylene tanks or try a search on the internet.
 
Dec 2, 1997
8,725
- - LIttle Rock
Heat welding is the only way to repair a PE tank...and if the weight of the contents pulls the crack apart, the weld won't hold. So I'm afraid it may be time for a new water tank.

Since it's an odd shape, Ronco Plastics is the only plastics tank mfr who's likely to have one that size and shape. They have more than 400 shapes and sizes, including 100+ non-rectangular, build top quality tanks for a very reasonable price and even install fittings in the sizes and locations specified by the customer. Ronco Plastics marine Tanks Most people find their older catalog a lot easier to search Ronco Plastics old marine catalog

Aluminum is an acceptable choice for a water tank (but NOT for a holding tank!) and has an average lifespan of about 20 years. You might find it less expensive to have one made locally.

--Peggie
 

DArcy

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Feb 11, 2017
1,702
Islander Freeport 36 Ottawa
Plastic tanks are really challenging to seal. Try a Google search for "welding polyethylene"
 
Jan 7, 2014
401
Beneteau 45F5 51551 Port Jefferson
I used west systems gflex to fix a hole in a kayak and it's been fine. gflex is different than 105 since it flexes a bit. maybe some 4200 would also work make sure its compatible with potable water first
though.
 
Jan 7, 2014
401
Beneteau 45F5 51551 Port Jefferson
this kayak was cut in half and glued back together. The guy looks to be about 175 pounds. the force exerted on the joint is probably 4 times that.