Damaged gas tank has slow leak... repair options?

[andynogo]

I usually solder tanks up. Much less heat than brazing (which does work well) so might be easier for some.

Clean the tank out with degreaser then soapy water, blow it out till there's no trace of petrol in it.

Clean the paint off around the entire area to be fixed plus a bit, heat up with a small blowtorch or a really good powerful soldering iron, use baker's fluid or similar steel flux and tin it up with ordinary solder. Works a treat.

 

[machiasmort]

Not bad advice Andy. I'd stick w/ a propane torch though! Unless you can get directly behind the hole with the iron.

 

[w31john]

I cut them off and weld on the next bigger size allen bolt

 

[radrob]

i called jbweld . they said the original is the best if its dry and you have the time. but jbstick will dry with the presence of gas.
i have had 2 of my first 3 tanks leak.

 

[Al.Fisherman]

Brazing works well. Empty tank (well, of course) flush, flush again and braze with the cap and valve off. I did a Honda trail 50 tank that had pin hole rust all over the bottom. I pretty much brass plated the whole tank bottom. Had the bike for ten more years and it never leaked again. The poduct Kreem works well I hear but it's expensive and was more than I wanted to spend for the little Honda. I think a new tank would cost much less than Kreem for a HT engine kit.

That is what I'd do and that is braze it (do it right). Don't flush with water..here is a sure way to neutralize the gas and fumes. First empty any fuel in the tank, tip and use a rag. Attach a hose to a exhaust pipe (I use my Miata) and force as much exhaust into the gas tank you can. Do this till the tank gets good and warm...braze away. If you think this is BS try this sometime, take a container like a tank, leave a little gas in the tank. Flush with exhaust till tank is good and warm. If any fuel remains pour on the ground and try to ignite it...can't be done. When ready to braze, pass the torch by the inlet...you might get a LITTLE poof (less then a real good f**t), and that's it.
Someone mentioned solder...that is good also.

 

[radrob]

true thats how the brazed my tank in me volkswagen scirocco. fired up a lawnmower engine hooked up a hose from the exhaust and brazed away!!!

 

[dirbob]

gas tank repair

In the old days we used a chemical called Triclorethane to kill the gas fumes in a gas tank. If you can find Triclor just put it in a sprayer and spray the in side of your tank. It will kill the gas fumes and you can weld on it all day. We used to kill a 10,000 gal gas tank with about a gallon of it, and then would cut it in half with a cutting torch. Hope this gives you another option. Bob

 

[MotorizedMitch]

I damaged a gas tank when I took a spill on the bike, and now it's got a slow leak. It appears to be leaking from the base of one of the mounting posts- the post is a little bent, and it's created a crease where the post joins the tank. I can't see with the naked eye if there's a fracture in the metal there, but evidence suggests that's the case.

I figured I'd just buy a new one until I saw how much they're going for and how much it costs to ship 'em, so now I'm curious about repair options. I know a guy who welds, so I could ask him about that, but welding and gas tanks just don't sound like a good combination. Are there any other viable options? Epoxy? Silicon? Duct tape?

Just had the same thing happen to me more or less. After searching the internet and brainstorming this is what I came up with. Prep area and use jb water weld around mounting posts where leaking, and use a washer over top that will cover cracked area, push washer into jb waterweld And let it fully cure. Then cover washer with jb waterweld and let that fully cure, ill let you guys know how it holds out as it should work better then the common technique of just using jb waterweld.