Tank Liner Recommendation

[peterg]

I removed the emblem tabs from my Special tank, bondoed it had it professionally painted 3 years ago. It seems like gas is seeping through the bonding to beneath the paint on the left side. Can anyone recommend a good tank liner? I’m hoping not to have to sand down to the metal and weld repair it.

 

[DogBunny]

Caswell is #1. Will seal leaking tanks. Works with ethanol gas.

 

[peterg]

Thanks. Looks like a 1/2 tank epoxy kit is the right amount. But for a few more buck might as well get the pint kit.

 

[grizld1]

+1 re. Caswell; I've done three tanks with it, great results every time. Be sure to follow instructions on ambient temperature carefully. If temp is too cold the epoxy won't flow well, and if it's too hot the epoxy will start to set up before you've had a chance to ensure complete coverage.

 

[peterg]

Thanks Grizld1.

I’ve ordered a pint kit.

 

[peterg]

Any suggestions on how to treat the petcock bolt holes prior to pouring the gel in the tank?

My tank isn’t rusted. Is it necessary to swirl around drywall screws as per the instructions?

 

[DogBunny]

Put bolts into the petcock bolt holes. Take them out when the epoxy has turned to Jello or stiffer.
If your tank is decent (or not), there is no reason to prep it. Caswell will work on rusted tanks, or on tanks that have been previously treated with Creme or other liners that are failing or peeling, with no more prep work than blowing out anything loose.

 

[peterg]

Sounds good. Thank you.

 

[TwoManyXS1Bs]

A Caswell experience...

Post #3315.
http://www.xs650.com/threads/what-have-you-done-to-your-xs-today.32082/page-166#post-531940

 

[peterg]

Thanks TooMany

 

[OHRider]

I have had good luck with POR 15 in 2 tanks.

 

[peterg]

Below are two photos of my tank.
The first one is pre-bondo state. You can see where the welds were that tacked the emblem bracket in place. I used a dremel grinder to remove the welds and probably took out too much of the tank metal.
The second one is post bondo and painting showing the bubbles that formed where gas leached through small pinholes and saturated the bondo. At least that's what I'm assuming happened. Any ideas on how to get rid of them short of sanding and re-bondoing? Would applying heat and rolling work? Or ironing? I've never worked with bondo before so don't know what can be done when it's been saturated with gas.

 

[gggGary]

Hypodermic needle and super glue have a clamp ready to press it down? not so sure you won't continue to have bubbles form, once gas gets under the paint.... Kinda late for you but you don't need to remove the brackets just tap the ends back a bit and bondo over them. I've found intact brackets ready for use after pulling the bondo out of the recess many times.
POS heating bondo with a heat gun makes it easy to remove.

 

[peterg]

Kinda late for you but you don't need to remove the brackets just tap the ends back a bit and bondo over them.

I'll know better next time. Bubbles may not have been the right word. I suspect the bondo has swollen up like particle board does when it's been exposed to water. Is that possible?

 

[kshansen]

I'm thinking that maybe the best plan of attack would be to use heat gun to soften the Bondo and clean it all out. Once gas gets in it probably just keep happening.

Then I would be looking for a good epoxy to fill and seal the pinhole leaks. Then once they are sealed have at it again with fresh Bondo. Might even be a good idea to coat the inside of the tank with something like Caswell or you choice of sealer.

I had very good luck with the Caswell on a tank on an old Farmall that developed leaks where the mounting brackets were spot welded on back in the late 1940's. It's been bouncing along for over two years with not a sign of a drip.

 

[azman857]

Like OHRider, I used POR-15 on my tank. It set up as hard as a rock. I'm sure it sealed up a crack I had along the back seam where I dropped the tank and it's still gas tight after a couple years and many miles.

 

[peterg]

kshansen - i'm trying to avoid sanding the bondo down but that's probably wishful thinking.

I have a Caswell gel kit in hand so will be able to stop any more gas from seeping.

azman and ohrider - after extensive research (this thread!) I decided to try Caswell.

 

[azman857]

I'm sure it's good stuff. Hope it works well for you

 

[gggGary]

I've had several gas tanks with paint ruined by gas seepage.
The Ersatz indian paint is bulged by the "gas gauge tube fittings" .

Neither of these are my "artistry".

Apparently it's OK to bondo and glass in a different gas cap, no metal needed. The tank on madness when it got here. There was a cool flush type cap just stuck in the hole!
It's not always aftermarket either.

When I poured in some acetone it ran right out of these areas. 30 year old glass, prolly got some ethanol too.

 

[peterg]

Has anyone used Permatex Fuel Tank Repair putty on the exterior of a tank? My intent is to use it then bondo over. I’d prefer to have the small hole welded but I don’t have a welder (machine or person) at hand.