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I need to seal pinhole in a petrol tank without welding? Answered

i have a leaking petrol tank (pinhole size) Can it be fixed without welding?

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Josehf Murchison (author)2014-03-31

OK clean it and fiberglass works great I have rebuilt entire gas tanks with it, funny all of them on Fords vehicles.

However if it is just one hole a sheet metal screw and a rubber washer.

When you screw the screw into the pinhole the rubber washer seals the hole.

Joe

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user

I used a similar method on the top of a badly neglected motorcycle tank about twenty years ago using small round headed screws it had about twleve pinholes in a cluster about three inches across; when a friend asked what all the little bumps were I said they were braille filling instructions for the former owner who was blind; it took him about ten minutes to realise what I had said ;-)

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CabbitCastle (author)2014-03-31

Bondo is usually a body filler for more or less cosmetic work - I doubt that it would withstand fuel contact.

I'd recommend various gas / fuel / petrol tank epoxies.

Go to Google / Amazon / eBay / whatever and look for "gas tank epoxy" or "gas tank sealer". If the site has a rating system, go for the higher-rated ones and check the comments as well. Carefully read the supplied instructions and use / apply exactly as described.

Results include Permatex 80884 Gas Tank and Radiator Repair, J-B Weld 8267-S SteelStik Steel Reinforced Epoxy Putty Stick, J-B Weld 8277 WaterWeld Underwater Epoxy Putty, the list goes on. You will need to choose your epoxy based on the material your tank is made out of.

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rickharris (author)CabbitCastle2014-04-01

Bondo is fibreglass base and should be fuel proof.

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CabbitCastle (author)rickharris2014-04-02

You are correct:
Checking 3M's FAQ it indeed states that Bondo is gasoline-resistant, but it can only be applied to metal tanks and cannot be submerged in gas.
I still think epoxy is the better choice though.

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nkerr1938 (author)2014-03-31

I bet JB Weld would work also

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iceng (author)2014-03-31

I solder closed a puncture in my gas tank.

Don't use a propane solder pencil !!!!

Use a grounded electric solder iron.

Gasoline specific heat does not sink heat away like water would allowing solder to wet a steel tank with fuel and seal the hole.

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iceng (author)iceng2014-03-31

BTW I was young, and kind of impulsive ... and

Gasoline did not have carcinogenic additives those days.

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steveastrouk (author)2014-03-31

You don't say where you are in the world, so its hard to be specific, but you should look at "POR-15" and their tank repair kit.

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rickharris (author)2014-03-31

Bondo or equivalent, you can or could here in the UK buy a petrol tank patch - probably illegal now.

Really you should look to change the tank. IF it is leaking in one place - It will be leaking in others soon.

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