gas tanks

[augermac]

Getting ready for paint on my 51 Pan restore-tanks are stripped was wondering about consensus about having tanks sealed,have heard form others that they had radiator shops seal them but they drill a small hole in tanks and that in time have failure with this process.Any thoughts,Auger

[exeric]

Pressure test the tank first. You can make up fittings to use the gas bung on the bottom of the thank, and seal the top with a regular cap. I like to use a bicycle pump, but you can use a compressor with a flow valve, or regulator. Of course you will have bubbles around the gas cap and bottom fittings, but with careful examination, you will be able to spot the smallest of leaks on the welds, or around the shifter bracket. Worst of all is an internally rusted tank that is rusting thin, with pin holes. If that is the case, it is most expedient to use a sealer. There are plenty of threads here, and on sites like CAIMAG that go into great detail on prepping a tank for sealer. I seal my own tanks and use Red-Kote, but everyone has their own preference.

[T. Cotten]

Auger!

The easiest and safest way to pressure-test a tank is to cork it up and submerse it in a tub of hot water.
You will want to rinse any soap off thoroughly anyway, as it is corrosive.

I do not advocate any sealer (except for soldered-construction tanks).
Sealers are difficult to remove if any future repairs are necessary, and the paint will always be sacrificed.

Phosphate coatings can prevent internal rust.

Good luck!

.....Cotten

[D.A.Bagin]

I had the unfortunate situation where on my 440 I had sprung a leak at the top of the tank adjacent to the gas cap on the soldered seam. About a 3/4 inch split. I repaired it neatly with JB Weld and it held perfectly. I had another leak show up at the rear mounting tab where it mounts to the frame. Rather than risk anymore than I already had it was time to bite the bullet and get in line for Matt's repro tanks from Iron Horse corral. After receiving them I pressure checked them at 4psi and used the soapy water process to check for leaks. I found none and decided after reading the horror stories about sealer that either wasn't used on a properly prepared tank or failed for some unknown reason chose to do without. So far after 3 years I have, ("Knock on Wood"), not had any issues. I guess after this long drawn out story you make your own decision on this but if they check out with a pressure test "I" would not seal them. Granted "I" was dealing with new metal welded tanks and you are in a different situation, so make the decision based upon condition after stripping, inspecting, and pressure checking them.

[augermac]

my tanks are solid,don;t know how that happened have been stored and moved many times since late 70's..more concerned about rust ,pressured tested no leaks..still very solid tanks.thxs for input Auger

[augermac]

thxs for info..will consider Auger

[augermac]

thxs for info tanks pressure tested ok..was more concerned about rust,Auger

[exeric]

The alcohol in modern gasoline has been a huge problem in humid places like Florida. In my case, if I know I'm going to park a bike for more than a month, I have to drain the gas out of the tank. I've only mentioned the alcohol; there are other mystery chemicals in modern gas that are pure hell on some metals, and synthetic materials. That is my reason for using Red-Kote, and I think it has preserved my tanks. Tank lining is a passionate topic, so I will not recommend it; that's up to the individual.

[T. Cotten]

Auger!

Just google "phosphate coatings"; There are many to choose from...
The hard part, with any treatment, is preparing the insides.

As I implied previously Folks, soldered-construction tanks (of which Panheads' are not..) are their own purgatory.
Red-Cote survived my immersion tests perfectly a couple of years in a row, however an Indian associate tried several times, with scrupulous attention upon modern reproductions, to seal a micro seepage using it, and failed.

There is no 'silver bullet'.

....Cotten

[exeric]

I agree, Tom; there are no guaranteed procedures, or results for marginal antique gas tanks. You work with what you have, use your best judgment, and try to do a superlative job.

[T. Cotten]

Eric!

The Indian tanks I mentioned were new, from Germany (perhaps manufactured in India?).

I assisted my associate with re-soldering the area; He held the heat gun while I worked the iron.
Although I wasn't there when he tested them, he is quite qualified, so the seepage was diabolical.

My point is magical sealers don't exist.
And beware Folks: JBWeld, which I used to swear by for its fuel resistance, failed the last two years in a row in my immersion tests.
(No time for a test this year...)

The fuels are constantly changing, and combining brands seems to make things worse.

Back to Auger's concerns,
Prepping tank internals demands aggressive cleaning, and even my tumbler with aquarium gravel has its short-comings.

....Cotten