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 ;-)
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.
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.
Discussions
5 years ago
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
Answer 5 years ago
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 ;-)
Answer 5 years ago
Now that was funny ;-)
5 years ago
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.
Answer 5 years ago
Bondo is fibreglass base and should be fuel proof.
Answer 5 years ago
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.
5 years ago
JB Weld for certain.
5 years ago
I bet JB Weld would work also
5 years ago
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.
Answer 5 years ago
BTW I was young, and kind of impulsive ... and
Gasoline did not have carcinogenic additives those days.
5 years ago
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.
5 years ago
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.