I have a hairline crack in my gas tank so small you can barely catch your finger nail on it. Instead of spending a whole day removing it and putting on a new one, I was wondering if anybody knew of a confirmed product epoxy or otherwise that would work to patch it. Some of my research has narrowed it down to " Marine Tex Grey " is good for a lot of Metal patches and a lot of people have said JB Weld gas tank repair did not work.

 

Here is the problem with surface patches, they can not hold/stick to the plastic because of temperature changes, and the plastic used in gas tanks must be chemically resistant to most, if not ALL, glues, or gasoline would eat it away, so double whammy.

You can weld plastic, that's how they make some plastic tanks(weld two halves together) and how they/you can fix it.

Good DIY article here: Repair Plastic Fuel Tank: 3 Steps

A lot of shops can weld plastic gas tanks as well, not too expensive, and no dropping the tank if you can get to the crack/leak as is.

 

Ron, Mine is a metal gas tank and some unconfirmed info I have read was Marine Tex Grey is a good product. Just don't know anybody who has used it.

 

JB water weld and JB tank weld both work for fuel tank repairs but like Ron said they are temporary fixes, even on a steel tank they will not last. don't know anything about marine tex grey. I'd fix it once and be done with it instead of trying to rub magic potions on it, epoxies are great for emergencies but not lasting repairs. Just my opinion.

 

Epoxy can hold/bond better to metal than plastic, but the metal still expands and contracts with temp changes so temp fix