PIn hole leak in plastic fresh water tank

[fontmell]

Help please
I have small leak in plastic fresh water tank which I can see but without major dismantling cannot get at!
Any one know of something to put in tank that will seal from inside and not poison the crew
Many thanks

 

[macd]

The tank's probably polypropylene or polyethylene, which practically nothing will reliably stick to (although both can be welded). If you're confident of the precise location of the leak, as a short-term fix, a self-tapper with a neoprene or similar gasket might work, but it would be no more than a bodge.

 

[vyv_cox]

We used to seal holes in footballs with a spoon handle heated in a blowlamp but I don't think I would try it with a water tank. As Mac says a self tapper is the best bet. Assuming you mean a solid tank, not a bag.

 

[bigwow]

Gentle use of a soldering iron, worked on my Vetus exhaust:encouragement:

 

[Pete7]

The plastic rings which hold beer cans together was a favourite for repairing skis, melted with a lighter and dripped into scratches before filing flat. Used the same idea to repair a trailer mudguard when I miss judged the gate post.

 

[matthewriches]

Miliput any good stuck on the outside of the tank?

 

[Irish Rover]

Did I misunderstand the op or did he say he can’t get at the bloody thing?

 

[Caer Urfa]

Agree with Bigwow if you can get at it and touch it with a hot soldering iron the plastic will melt and seal the hole if it so small

 

[QBhoy]

By your description, do you mean you can only get at it from the inside ? If you can get to it from any side...CT1 will seal it.

 

[thinwater]

Neither CT1 not Milliput are rated for polyethylene. They will likely peal right off unless the surface is properly prepared, and probably even then. Note that epoxy is mixed in PE cups, and it pops right our when cured, and that sealants like CT1 have PE spouts, and it does not stick to them even when cured.

Sure, a screw might work if it was a drilled hole, but if it is a wear spot or a crack it will make it worse fast.

 

[macd]

Did I misunderstand the op or did he say he can’t get at the bloody thing?

He wrote that he could see it, which may mean he can contrive to get a screw to it on the end of a driver. He might even be able to drill a pilot hole with a slim electric driver. If he can't, he can't.

 

[sailaboutvic]

Has Mac said a screw with plenty of seikaflax , I did one on mine like that the other year and still dry

 

[fontmell]

Thanks all responses
As said can’t get at it without dismantling big time
Don’t you just love boat builders!
Is there a chemical to put in tank anyone knows off like Rad seal

Thanks

 

[Tranona]

Thanks all responses
As said can’t get at it without dismantling big time
Don’t you just love boat builders!
Is there a chemical to put in tank anyone knows off like Rad seal

Thanks

No.

 

[macd]

Is there a chemical to put in tank anyone knows off like Rad seal

There's no point putting anything in the tank unless it will bond to it, and nothing will (assuming my presumptions about the material are correct). The only exception I can think of, and it would be a poor one, is to line the entire tank with an epoxy film (such as used for some old GRP motorcycle tanks), but to do that you'd need to swill it around -- in other words, take the tank out.

P.S. Come to think of it, any sort of poured-in lining would be worse than poor, and probably short-lived in its effectiveness.

 

[PTB]

Can you get at the top to put an inspection hatch in and then do the self tapper thing from inside?