V Twin tank sealer?

[FNG1]

Hi Eric, I am asking because I thought all factory tanks were treated. I think I am going to try Harleytoprocks idea. After reading up I wonder, does the parkerizing prevent rust, or is its ability to hold oil that does it? Does gas (refined oil) help, hurt, or do nothing? Now my head hurts. Does anyone have some years on a set of untreated repop tanks that could say how they held up? Does anyone have a set of 41-46 OHV tanks that need repaired they would sell? I'll follow up if I park them or piss on em and leave them untreated. Five or ten tears down the road any tank that rusts or leaks..... Well thanks all for the great input

[exeric]

Parkerizing will inhibit rust so it would be better than bare steel. However, there is no reason why repro' un-lined, un-treated steel tanks shouldn't last for many years. What gets them is sitting for months on end with just a 1/4 tank of ethanol, because rust will occur. If the tanks are going to sit indefinitely, either fill them to the top with gas, or drain them. I prefer draining them.

[FNG1]

Hi Eric, good to know, I wondered how they would hold up as is. I,m hoping for better than untreated and have some new ideas thanks to this forum. Thanks again.

[harleytoprock]

You have to identify your goal for using a sealer. Is it to stop leaks, stop future leaks or prevent rust? The sealers on the market are good for any of those goals but at the risk of fuels attacking the sealer or the sealer not adhering to the tank inner surface. Sealers like redkote or kreem dry by evaporation of the solvents. I said dry and not cure because I believe these sealers can be attacked by similar solvents. Much like dry lacquer paint can be dissolved with lacquer thinner at any time. Epoxies(2 part) and urethanes use a chemical curing process. Por15 (a urethane) cures by reacting with moisture in the air. Other urethanes cure by a chemical catalyst. (Isocyanates). I think either moisture or chemical type will accomplish the same final urethane product. Adhesion will depend on surface preparation.Epoxy coatings, like Caswell's likes to stick to rusty surfaces and seals off the rust from future moisture contact. I think that preparation tank tumbling in a clothes drier, with nuts and screws will not improve adhesion. It's more of a vibratory process which makes the metal appear clean and pretty but polishes the surface to a degree that prevents good adhesion. Sandblasting would be great if you could get to all of the surfaces. So that leaves acid etching.
A big concern with ethanol gas is that the alcohol content absorbs moisture just like DOT3 brake fluid. This junk becomes corrosive in tanks and carburetors.
Parkerizing will do nothing to prevent leaks but unlike a polymer sealer it can not be dissolved or attacked by solvents and fuels. Parkerizing is a conversion process of the iron in the steel. Since it's not a coating, it can not peel off.
It's all a crap shoot to some degree. But to have success with any product all of the steps have to be done right.

[T. Cotten]

Folks,

Many of you may remember that I test my local P4gas annually by applying various paints, sealers, adhesives, etc. to etched glass plates, and then immerse them for observation.

Red Cote has survived well, so far, but Caswell's failed after many weeks, and POR15 rarely lasted overnight.
Please remember that this is an assessment of my local fuel only, and combinations of brands may be more digestive than any one alone. To confuse things even more,"Seal-All" failed in years past, but survived admirably in last year's summer blend. Yet "JBWeld", which used to be fuel-proof, has failed the last two years running.
So its all about the fuel.
Ethanol is obviously a major culprit, but the percentage has been 10% for decades. ("Gorilla Glue" separated from the glass in P4gas, but not in ethanol-free!)
Otherwise, there are ~150 various federally mandated additives, many proprietary, and combinations may well be synergetic. (We won't consider illegal dumping of solvents unless fuel gets back to four bucks a gallon.)

The tried and true isocyanate I use is TNEMEC's Omnithane 530. But my buckets are quite old, and I am not certain if the formula has changed since I obtained them.

I really do not know if fuels will compromise parkerizing, but I know 'dry' parkerizing will rust.
There are probably other phosphate coatings available as well.

....Cotten

[FNG1]

Hi Harleytoprock, My goal is corrosion resistance. Acid etch sounds like the way to go for prep. I asked to take advantage of others experiences so I don't have to find out the hard way. I stumbled onto zinc plating. Maybe I could fill the tank with the electrolite, hang some pure zinc in it, connect up the battery charger, and let it go to work? Some more hours on the web and it sounds doable. Not enough time this week. I will let you know. Thanks again for the information.

[FNG1]

Hi Cotton, I like your no nonsense style of testing. I have done endless testing with alcohol, and it always ends with me studying the bottom of an empty shot glass. I found out from some of the gun sites that parkerizing (and blueing) creates a surface to hold oil. Still I think that it would help in gas (I'm geussing now) because gas is refined oil. That said,I want to try the zinc plating idea. Any thoughts? I hope this is no longer about cheap repop tanks and becomes more about metal preservation.

[T. Cotten]

FNG!

I really don't know if the gas-is-oil theory works with Parkerizing, as I really haven't the chemistry background to understand its affinity with oils, other than petrolatum lasts a lot longer than WD-40.
Gasoline and water shouldn't mix, but ethanol and water do. When it gets to five percent of the ethanol, it separates from the gasoline, and then the bottom of the tanks are exposed to it.

Zinc sounds alright, but how do you get every bit of the insides covered? Beware that gases will undoubtedly be released, and hydrogen can be quite exciting if ignited under pressure.

....Cotten

[jim d]

When I pressure test a tank I would expect the tank to hold the 3 lbs. for a few days with no leak down. If it lost pressure I would use soapy water to locate the leak. But I have used hot water and froze the vessels to locate leaks on smaller items such as floats. I have also used a constant regulated pressure to check intake leaks.

[T. Cotten]

Jim d!

I would be quite surprised if any caps would hold pressure for that long, even overnight. Most gauges don't read accurately that low, and it would be difficult to be certain if it was the caps or a leak. So why not just go straight to a bathtub test?
Submerged in a hot water, soap would only get in the way.
And there would be no risk of over-pressurizing and bloating out any flat surfaces. (I found out the hard way on an oil tank, decades ago!)

Believe me, I believe in soapy water (http://virtualindian.org/11techleaktest.html), but its always best to keep it as simple as possible.. and a tub of hot water is.. more simple.

...Cotten

[FNG1]

Hi Cotton, what I read about zinc is that it is sacrificial and would protect until it was gone. Well I got Some klean strip phosphoric prep and etch and some coiled sheet 99.% pure zinc for protecting you roof shingles. I will set something up to experiment on and take some pictures and let you know. But not this week.

[exeric]

Hi Cotton, what I read about zinc is that it is sacrificial and would protect until it was gone. Well I got Some klean strip phosphoric prep and etch and some coiled sheet 99.% pure zinc for protecting you roof shingles. I will set something up to experiment on and take some pictures and let you know. But not this week.

That is a great idea FNG1, and would be a great aid to help solder repairs on an older tank. Thanks for the suggestion, and I found a sight that details a home zink plating process.

http://thefactoryfiveforum.com/showt...uts-and-Bolts&

[T. Cotten]

That is a great idea FNG1, and would be a great aid to help solder repairs on an older tank. Thanks for the suggestion, and I found a sight that details a home zink plating process.

http://thefactoryfiveforum.com/showt...uts-and-Bolts&

Gosh Eric,

I doubt "older" terne plate soldered tanks would take the plating.

The are doomed to a "sealer", although an associate of mine could not seal an invisible pinhole in his Indian tanks (modern soldered-construction reproductions) even with multiple applications of Red-Cote.

....Cotten

[exeric]

There isn't much of anything but rust left in most of the old tanks I mess with

[jim d]

Tom
You make some good points but my tester dose not leave the cap on for testing. It replaces the cap and only covers the top of the bung so that seeing a leak in that area is not a problem. It is also universal so it may be used on all sizes of tank openings. The tester uses all rubber seals including a 1/2 in. thick one between the tester and the top of the bung. Incorporated into it is a 1 1/2 in. Ashcroft 0 - 30 lb. gauge made in USA that reads in 1/2 lb. increments to monitor and avoid over-pressurizing the tank. The last tank I repaired was a leaking oil tank in a Chief with tanks silvered soldered together. That required cutting a hole in the none leaking gas tank to repair the oil tank testing it and then repairing the hole in the gas tank and testing it. With the oil tank being in the gas tank putting the tank in water and watching for leaks inside the gas tank would be a challenge. So I made a tester that I could put a few lbs. in and let it set for 3 days. This was a lengthy repair and one I didn't want to revisit so I wanted to be sure there were no leaks. I have used water to test tanks before and it works fine. A pressure tester just lets you watch for leaks over a much longer period of time or where you can't see as well. I will see if I can figure out how to post some pics of it or I could email or text them if some one is interested.