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Fuel Tank Sealer Botched Job

The original toaster tank on my 51k, /5 project has no rust inside but the OEM inside coating is showing its age. The outside will be re-painted.Having used POR-15 in the past on worse vintage tanks(inside rust) I was leaning toward another POR-15 job but now thinking Red Kote is the way to go? Any other ideas out there?

FWIW, one of the things you have to watch out for when you seek & try to apply information from various "tech Lines" such as mentioned here (but not meaning to point at POR-15's tech line) is that they are knowledgeable about their products but often lack "application" skills or knowledge. Don't expect them to know how to use the product in the shop as would a skill trained tradesman.

Another benefit with Red Kote is it has an almost indefinite shelf life if you seal the can after using it. I used the same can a week ago that I bought 12 years ago and it worked perfectly. I have some left over and will buy some more so I can do all the project tanks sometime this Winter before I get paint put on them.

Por-15 is some great stuff but its no match for the Red Kote!!!
 
My choice for Red Kote was so the original red coating could be duplicated or preserved. That did not work out. I don't think there were any pin-holes in the tank, but the original coating was starting to flake based on the petcock screens.

I used ~ 1/2 gallon of superclean in the tank and let it sit for about a day. All the original coating was removed. Multiple flushing with water got the coating out. Since I was in that far: 1/2 gallon of etch-n-prep was added to the tank which was then agitated for ~ 1/2 hour. The etch-n-prep is phosphoric acid, the superclean is sodium hydroxide. The tank was flushed multiple times with water.

Three coats of Red Kote were applied after letting the tank dry and rinsing with acetone and MEK. I rigged up a hair dryer set on low to help dry the tank. The original red coating was not duplicated after applying the Red Kote.

In hind site, I would have been much more careful about taping and covering the paint. But, it was not too bad - primarily because I understood not to try and clean the coating if any got on the paint. There are now some red hue areas from the coating that I expect will eventually fade when exposed to sunlight.

My tank has the original paint that was not in great shape before coating. So, it was not a catastrophe that some coating got on the paint. Overall, I would do it again but be much more careful with taping and covering the tank paint. My experience may not relate to yours. YMMV.
 
Along with the use of chemicals, something that will help break off coatings of paint or rust is to put some washers, screws or other small objects into the tank and give it a good shaking. I had an old Triumph gas tank that had rust in it, I used a box of 1 inch drywall screws. It won't get everything out, but it got most of the rust out of the tank before going to the chemicals.
I counted the number of screws that went in each time and made sure the same number came out.
 
There is an ongoing thread on ADV in "The Garage" section, r.e. fuel tank renovation that makes reference to www.rusteco.com . I just read the website as pertains to MC's & there is some good info., however the product is very expensive! Cost $125 for enough for a 5 gal. tank! Anybody used this stuff or have knowledge of what the magic solution might be in a more affordable source?
The ADV thread has several other experienced comments on tank renovation.
As to the above "shake & clean" method-I've done that one but it's worth saying(never know who might be reading this) that you best not have any gasoline in the tank when you do so!
 
I am currently doing the tank(s) on my Indian Chief. I am using epoxy from Aircraft Spruce. For anyone doing a tank interior project, it would behoove you to buy a "Digital Inspection Device" from Harbor Freight.
 
I am currently doing the tank(s) on my Indian Chief. I am using epoxy from Aircraft Spruce. For anyone doing a tank interior project, it would behoove you to buy a "Digital Inspection Device" from Harbor Freight.

Totally agree, in that I borrowed one from my buddy down the street and what I saw on the other side towards the rear of the tank made me very sad, then madder than H e double tooth picks to think someone made this lovely mess and now I come along to clean it up. Will be getting the tank back shortly and will give a full report with pictures.
 
Remember, epoxys formulated for fuels back in the late eighties and early nineties had no idea the concoctions of booteeque fuels that the feds have come up with in our postmodern era. There was a time when gas was gas. Can't imagine the coatings of today will last much longer than those from twenty some years back.
 
One of the bennefits of ethanol fuel is moisture goes into solution in the alcohol and out thru the carburators with the gas instead of forming a little puddle of water in the bottom of the tank and rusting thru the seam like in the old days.. Its the reason northerners put dry gas in their tanks in the winter to absorb the water an avoid frozen fuel lines. Its hard for me to believe that the minute partilcles going thru a gas filter would prop open a needle valve. I'd take a really good look at my float conditions first. They are the classic over flowing carb source.
 
One of the bennefits of ethanol fuel is moisture goes into solution in the alcohol and out thru the carburators with the gas instead of forming a little puddle of water in the bottom of the tank and rusting thru the seam like in the old days.. Its the reason northerners put dry gas in their tanks in the winter to absorb the water an avoid frozen fuel lines. Its hard for me to believe that the minute partilcles going thru a gas filter would prop open a needle valve. I'd take a really good look at my float conditions first. They are the classic over flowing carb source.

Sorry for the delay as it has been overly busy in my world. Here is what finally happened on the messed up POR 15 tank liner.
I phoned POR 15 on there 800 # and spoke with a technical person who amazingly enough understood and had sympathy for me. Advised that you can remove the POR 15 chemically using anything that is a Methylene Chloride base. Products such as Mystripper, Liquid Aircraft Paint Stripper all works extremely well. The tank has to be throughly cleaned with clean hot water. It then has to be etched to allow any other tank liner to used. He said several times that the biggest reason POR 15 sometimes fail, is that people do not dry the internals of the tank to remove any traces of water.
Now the fun began.
I hunted all over Western Canada for the Red Kote product and no one would sell me enough to do my tank. However found a radiator shop here in Calgary called City Radiator who said and did take the tank, stripped the POR 15 out and relined the tank with Red Kote twice. Was not cheap, but it saved me time and the cost of getting rid of the left over chemicals. Nice part is that they did screw up the outer paint, even though it will have to be repainted someday.
End of story, in that POR 15 is gone, Red Kote is now a beautiful red color and I know my Bing Carbs will now perform the way they are supposed to without get clogged with that fine white powder we are all familiar with at the bottom of the tank.
I am glad the water has finally gone under the bridge on this situation.
I will post some pictures towards the end of the week.
 
Rusteco

As kentuckid mentioned, this product is definitely worth a look for cleaning and de-rusting tanks. IT WILL NOT DAMAGE PAINTED SURFACES, NOR WILL IT DAMAGE YOU.

Yes, it's expensive, BUT CAN BE RE-USED SEVERAL TIMES FOR SEVERAL TANKS. I store mine in a 5-gallon gas can I bought for the purpose. IF you absolutely, positively do not want to re-paint your tank, $125 is pretty cheap, IMHO.

I have some working in a BMW tank right now, and will let folks know how it comes out. My previous treatments have been on an old Goldwing tank, which had no coating (other than RUST!) that I could detect. Goldwing tanks have "internal plumbing" that (generally) means you CANNOT use "coatings" successfully. Also used this SAME (used) batch on another tank (also "uncoated"), and it makes the internals shiny-new IF the only problem was rust.

I cannot (yet) address how successful this product would be at removing flaking original red coating, but will pass that along when my current "soak" is finished. I suspect that it will NOT remove old original coatings, nor would it remove POR-15 botched jobs, but that's just a guess. The techies @ Rusteco can tell all, or maybe their website can do.

Check out the website, and call them. Their "main" mission is de-rusting HUGE commercial equipment, such as bulldozers that have been buried in the South American rain forest for months and months. (Not kidding.) The workers using these big vats don't even have to wear protective equipment beyond what you'd wear to immerse your hands in water all day. . .NO fumes, whatsoever.

Once treated/de-rusted, this product provides an invisible layer of protection so it won't rust again. My old 'Wing's tank still looks great after two years, and this bike sits a lot, sometimes with only a half-tank of (Sta-bil treated) gas.

NO affiliation with these guys, beyond knowing that the product WORKS, as advertised. They'll also do it for you, out of L.A. Send them your tank, if you want.

Walking Eagle
 
Several months after coating the tank and having cleaned and reinstalled the fuel petcocks, I replaced them. I will eventually rebuild the originals, but having clean new petcocks is very nice. The new petcocks have a distinctive 'click' when rotated. Part of my reason for buying new was from running out of fuel on two occasions - because I reassembled the tubes backwards - and did not want a third incident (photo's should have been taken before disassembly). Since you have photo's that should not happen in your case.
 
Several months after coating the tank and having cleaned and reinstalled the fuel petcocks, I replaced them. ... The new petcocks have a distinctive 'click' when rotated.

Nice, huh? I finally broke down and sprang for new straight-through Karcomas (from Bing) for my toaster tank. I was going to swap them over to my 6-gal tank, but decided to just buy another set of new ones for it too.
 
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