Removing sealer from Gas Tank

I have to remove all the sealer in my tank, and was wondering what would work best. I have researched the archives, but didn't find much on cleaning sealed tanks. Who ever sealed it did a crap job. They sealed the inside of the gas cap, then drilled holes in the cap to vent it. It looks like they didn't even clean out the rust before sealing. I just want to remove and clean the tank. I was thinking of using 2 stroke oil, slick 50, or something like that to help keep down the rust after I get it cleaned out. I read on some threads that diesel fuel or kerosene works good to seal the metal too.

I am going to check out the local radiator shop to see what they can do, too.

 

i hear acetone is the stuff to use

 

I'd be amazed if anything shifted it! After all its designed to sit in petrol indefinately. You could try acetone but I have my doubts. Note this stuff is highly volatile/flammable/noxious.

IMHO I don't reckon any petroleum product eg diesel fuel will "seal" rust. You should be using rust converter

 

I was thinking the oil or diesel fuel to coat the metal after all the rust was removed. I would use either muradic acid or the electrolysis method to remove all the rust. I just don't want to recoat the inside of the tank. I personally know too many people that have had problems in the past with the tank sealants.

I am going to take it tomorrow to the radiator shop. They said they may be able to clean it out for me.

As for the acetone, I am quite familiar with it. We used to use it frequently to clean the optics on the lasers.

 

Fair enough...I presume you mean muriatic (hydrochloric) acid though? , I didn't know it was used for rust removal... I thought phosphoric acid was the silver bullet....

 

One of the two. It was also referred to as the cement acid. I was thinking the stuff you clean concrete. I think the salt water/battery charger thing would be the best.

 

Methyl Ethyl Ketone (MEK) would probably remove the old sealer as that is often the original solvent in the material. (Also highly volatile).

Phosphoric acid is the converter. Muratic acid is the one that will eat a whole in the metal...

 

Electrolysis....I wouldn't go there mate...the process produces hydrogen gas...mix that with any residual petrol fumes and well...you know the rest 8O

http://myweb.tiscali.co.uk/andyspatch/rust.htm

Sadly I think the MEK will only disolve uncured sealant?

 

i have a tank 4 sale if ya want it..its stock issue from a 82 xj650..
only one small ding looks like from a rock...will easily be fixable
with a little spot putty before the repaint...

 

I just got back from the radiator shop. The guy there says that it is Kreem liner, and he has tried everything to remove it. He said acetone makes it guey, but doesn't remove the stuff. The last one he did, they cut the tank open, sand blasted it, and put welded it back together. If it was another brand, he would have chemicals to remove it.

BTW: He told me that he uses muratic acid to clean all the tanks prior to sealing (with red coat), and that after cleaning out all the acid he uses MEK, a prepaint moisture remover you can pick up at your local paint shop. He gets it at Sherman Williams.

Looks like I will be running this tank for a bit, unless I can find one cheap, $30-$50 price range.

 

I have removed Kreem with progressive applications of paint stripper.
The thicker it is, the more stripper it needs.
In a way, first put nuts and bolt and stuff in it and break up the large pieces and get them out as flakes. Then put in stripper. That way you can use less paint stripper and get by.

I dont like redkote either. Heck I prefer Kreem to redkote. I have done POR15 but its near impossible to remove without blasting it.

Cool.
Srinath.

 

Went through the same problem. Check with another rad place or muriatic acid will remove it best of luck . Best to get that tank cleaned or else your carbs will cry.

 

As for the myths of muriatic acid eating metal it did not eat my tank but I would not leave it in there for too long maybe 1 hour at the max. But I strongly suggest for cost purpose to check with other rad places like I said I tried the Kreem thing and what a nightmare spent more money on the kreem and the acid then if I would of taken it right away to the rad shop.

 

Muriatic acid eats rust over 1,000 + times faster than it eats plain steel.

In fact with Kreem peeling in there you could put the muriatic acid in it and rinse like a maniac and get out all the rust and the crap etc etc etc out. Then rinse with hot water ... hotter the better. Some baking soda can help ... but very hot water is your best friend.
Then get the tank dry dry dry ... like put it in an oven at 200 or so and get it dry. As fas as possible the tank needs to be dry.

Then here is the trick, close off all the openings tight wihtout using duct tape, inner tube in the petcock and a rubber plug for the cap hole works OK. and it has to be really air tight ... get in plain pure acetone in there and slosh it, and it may take several hours of sloshing. Being air tight actually slows down the evaporation of acetone till its got the kreem nice and soft and goopy. You can add more acetone if you get evaporation losses but better to get in that 1 lot sealed tight and it should work.

Then open the top and let it sit for a while in 1 position, then slosh a little and sit in a different position etc etc etc for 2-3 days. It may re kreem itself quire well.

The Kreem is peeling cos its got rust underneath. That has lifted the kreem in some spots and that has lead to an enmasse peel off. The muriatic acid will get the rust and not affect the kreem. The rinsing will get the muriatic acid out. The trick is to get the acetone in in a dry tank which has not re rusted form the moisture of the rinsing. Then acetone softens the kreem and re coats everything. Just takes time and shaking. Its easier on a sport bike tank, you can cut a plate for the cap and put inner tube in it and bolt it in. This cannot be done with POR15, only with kreem, cos POR15 cures with exposure to water. Kreem just dries. It will actually work better in winter cos cold weather keeps acetone form evaporating that fast.

Cool.
Srinath.