Which JB Weld?

[FlyGuy65]

Small fuel tank leak at a topside rivet. Various threads researched mention Loctite 290 (green), and some mention using JB weld. However, there are a lot of variations of JB weld, or so it seems to someone who has not used it before. Which flavor would be best, if someone wanted to use it to hopefully seal a rivet? Would one also use this to fix a small cosmetic dent?

Thanks in advance!

[PilotjohnS]

I would not recommend JB weld since the compatibility with fuel may be unknown. Also I think the material needs to wick into the area and be compatible with the pro seal already in there. I would recommend what has worked in the past, like the specific locktite product made for this repair. JMHO.

[Larry DeCamp]

John,
I did the green loctite thing with initial success but had some leakage after a while. I use JB weld for cosmetic filler but I question its ability to adhere and penetrate the tiny source of fuel leak around a rivet. It may work.

What I do know is 3M2216 works. It is relatively low viscosity and the stickiest stuff you can imagine. I headed the advice of the Horton School of Composite technology by using the “ Credit Card Scrape for pin holes “to push the goo into the target area.
To minimize mess and avoid unnecessary contact with paint, I used a hole punch in polyethylene tape or packing tape. Make the hole about the size of the dimple and card the goo. Pull the tape to cure. I know it was auto fuel compatible for at least two years before the plane was sold.

[HFS]

I had a discussion with a 3M engineer back in 2011 re/the compatibility of 3M 2216 ScotchWeld adhesive & avgas.

He told me that 2216 could be used in contact with avgas with no adverse effects. As a follow on to his comments I have been "cooking" some cured 2216, submerged in avgas since that time (now going on 11 years), and whenever I pull out my sample for testing - I see no changes, looks just the same as when I put it in all those years ago.

YMMV - but on this question, I bet not.

HFS

[PilotjohnS]

I agree EC2216 is good and may work. But the question was about JBWeld; I dont think JBWeld is identical to EC2216, thats all I am saying.

[Roadjunkie1]

I know of one pilot who had used $$ProSeal$$ on a fuel leak in a non-RV aircraft. After it cured there was still a small leak and the airplane needed to be flown. He got some of the Quick Cure JB Weld and applied it to the areas that were obviously leaking past the $$ProSeal$$ after cleaning the area with pure Isopropyl alcohol (used to clean clock parts: no water). The small leak has disappeared and, at last report, has not leaked since. This was done about 3 months ago to an area that is in constant contact with fuel. Just the facts, ma'am.....