Fuel Tanks

[Paul prinzo]

I have sandblasted my fuel tanks and now there are several spots that have appeared that look damp. The tank did not leak and these damp spots are located where weld are. Anyone coat the inside of their tanks with a sealer?

[Freightrain]

I've patched/welded on mine for years.  Until I ordered new Aluminum tanks last year!!  No more leaks  LOL!!

I used to drain them down, loosen the straps and make sure the fuel was away from where I welded.  No problem.  It would find a new spot every few years, thus I replaced them.

[Hobert62]

I used a product called redkote in a antique johndeere gas tank before.            Dumped a quart in and rolled it around for awhile then turned it upside down to drain extra out.      Worked for the tractor, but I don't think I'd use it in a road tractor due to its red color.   

[eddeere]

Sealers should work if the tanks are clean and etched inside. Some radiator shops  will prep a tank with an electrode suspended in with a strong electrolyte solution and D.C. voltage . One of mine leaked after sand blasting . I filled it with Murphy's soap oil and  water brazed the area where the damp spot was. So far no leaks . A coating of epoxy primer on the out side may have helped some .  

[MHfred]

I know that many of you have coated your tank internals but I cannot bring myself to put anything into my tanks except the fuel that is used. I feel the odds are against me because there is too great a chance the coating will come off and cause more problems than the tank not being coated.

[Maddog13407]

coated my B model tanks with red coat, i cut the end caps off, had the tanks blasted in and out, red coated them with a brush and stayed away from where id weld the end caps on, welded caps back on then poured red coat in the tank and rolled the tank to coat the inside where the weld was. been runnin them since 2008 with no problems.

[Hobert62]

2 hours ago, Maddog13407 said:

coated my B model tanks with red coat, i cut the end caps off, had the tanks blasted in and out, red coated them with a brush and stayed away from where id weld the end caps on, welded caps back on then poured red coat in the tank and rolled the tank to coat the inside where the weld was. been runnin them since 2008 with no problems.

Did you get any color bleed to the fuel?   With the jd I did it sat about a month before I put gas in it.  I still ended up with a pinkish tint to the gas for awhile in the settlement bowl.  

Edited February 23, 2018 by Hobert62

[Maddog13407]

not that i have noticed. i have done a few gas tanks for B models with it also

[Hobert62]

Guess the diffrence could be on the tractor the sediment bowl is clear.    The truck tank is dark and prob couldn't notice it even if it did.   

[Maddog13407]

prob not, not sure if the red kote would be enough to dye diesel or not... i know i have used some kinda white kote stuff to on the inside of a gas tank and  to my surprise, the stuff ws hard as red kote but any contact with water and it flaked right off. got that at a motorcycle shop

[Maxidyne]

That was probably POR15, I've had good luck with it on motorcycle tanks, but keep in mind that you'll need a lot more for a big truck fuel tank than a 5 gallon or so motorcycle tank needs. There's also economics to consider- We spend big $$$ restoring motorcycle tanks because even if we can buy new or good used tanks, the prices are often over $1000. But many truck tanks are pretty much generic, so better to replace with new or good used than get into expensive repairs and unsafe welding on fuel tanks.

[steelman]

Two years ago, I coated the inside of the two fuel tanks on my toy hauler (freightliner).  On the way to Macungie, the truck shut down on the interstate because the coating came off and plugged up the fuel line.  I changed fuel filters, and cut them open, and found more sealant in the filter.  Had to clean the fuel lines, and cut the ends off both tanks and removed all of the sealer.  Put back together and have had no more problems.  I have over 45 years working with antique cars, trucks, engines, etc., and had never had a problem before.  I will not coat the inside of another fuel tank, especially a diesel.