gas tank restoration

[cbudvet]

Well last night I was looking closely at the inside of my gas tank and noticed "a thousand points of light". Crap, I was hoping my tank would be a simple clean and coat and that would be all. I am going to take it to a gas tank Renu place south of Indianapolis this Friday. Hopefully they won't gouge my wallet too much. I have taken pre-pictures and will take and post more pictures when I get it back. Carl

[webdawg1]

Yeah...I'll be getting mine back from (Moyer fuel tank renu) http://www.gas-tank.com/ here shortly. Was only $295.00, so it must not of been too very bad as far as condition....As I was expecting it to be more...So it was really nice when they said ONLY $295.00...So in other words, I'm a happy camper with that price...

webdawg1

[JimmyZ]

I'm finishing mine up. Did eloctolysis for a couple days using wahing soda and a little ospho. This stripped the paint and residual gas out of it. (Someone had coated the inside before) Cut an access hole in the top, sandblasted, and phosphoric acid treated it. I'll sandblast again and apply metal prep before applying RedKote. Redkote is a great gas tank liner and is used by my local radiator shop and others. It is something to look into at $31/qt. After having read all of the smear/neg advertising between Hirsh and POR I decided to stick with Redkote. The local radiator shop guy showed me the insides of a few tanks he was doing which had been coated by other processes. This greatly influenced me as well. It can be removed by soaking in MEK if one should need to remove and reapply. It also seal holes up to 1/16".

Here is a video I made using a sample of RK.

http://warbuddies.homestead.com/RedkoteTank_Liner.wmv

I hear that Renu is good and that they bascially do the same thing. They use a different sealer though. Seems that they would provide a higher quality repair than most.

[beandip]

I'm finishing mine up. Did eloctolysis for a couple days using wahing soda and a little ospho. This stripped the paint and residual gas out of it. (Someone had coated the inside before) Cut an access hole in the top, sandblasted, and phosphoric acid treated it. I'll sandblast again and apply metal prep before applying RedKote. Redkote is a great gas tank liner and is used by my local radiator shop and others. It is something to look into at $31/qt. After having read all of the smear/neg advertising between Hirsh and POR I decided to stick with Redkote. The local radiator shop guy showed me the insides of a few tanks he was doing which had been coated by other processes. This greatly influenced me as well. It can be removed by soaking in MEK if one should need to remove and reapply. It also seal holes up to 1/16".

Here is a video I made using a sample of RK.

http://warbuddies.homestead.com/RedkoteTank_Liner.wmv

I hear that Renu is good and that they bascially do the same thing. They use a different sealer though. Seems that they would provide a higher quality repair than most.

Jimmy , you might outline how you purged the tank before you started cutting into it . Other wise someone might blow up a tank with a spark .

[JimmyZ]

Ah yes... A good point. This is a very important part because of the severe explosion hazard. Should have put up a disclaimer like this...

Gas tanks pose EXTREME explosion hazards which have been known to kill or at least break a few bones while sending someone across a shop. This is something which should not be taken lightly. Before beginning any work on a tank one should remove all traces of gas or anything combustible such as varnish which may produce vapors. Gasoline itself is highly flammable but one should remember it is the vapors which ignite and not the gas itself. Stay at least 100 away from open flames, water heaters, electric motors and anything else which could ignite the vapors. If something should ignite the vapors in a tank, the openings are unable to release the pressure resulting in a serious explosion. I've met a survivor of such an explosion. His description wasn't pretty and he confessed he was very lucky to have survived. Handling raw gasoline is equally as dangerous and requires extreme caution. Place drained gasoline in a sealed, approved container as soon as possible.

End of disclaimer

Here is what my research has found regarding creating conditions for safely work on a gas tank. (Welding, cutting, anything involving sparks or heat etc...)

Since a mistake with a gas tank is a one time thing I'll list methods which have worked for some but should NOT be relied upon. Ususally the work being done on the tank was welding or sweating. The following methods though somewhat sound have FAILED at one time or another and should NOT be used...

Filling tank with water

Assuming tank that has set dry for a year is safe(Can't smell fumes)

Purging tank with exhaust pipe. CO supposedly negates combustion.

Purging tank with inert gas such as argon. (Similar to above)

Washing tank with water

Methods that work and what should be used...

Take tank to radiator shop for boiling and any welding/sweating req.

If you are doing it yourself...

Drain all fuel and place in approved container.

Use strong degreaser to thoroughly clean the tank. Clean tank until no residue is showing in waste water.

A good follow up for the degreaser treatment is electrolysis as this will liberate a lot of crud that the degreaser might have missed. Electrolysis has dangers of it's own so I will make a page for the electrolysis and place in a later post. It's cool and it really works well. One shouldn't rely on it to remove all rust inside a tank despite using internal electrodes.

Cut access hole in top of tank and sandblast. Stop occasionally and use a light and mirror to see what you've missed. When you have removed 90% of rust then drain sand and apply ospho to inside of tank. Let ospho set up for 24 hours and sandblast to remove all traces of it.

Conduct any sweating or welding on the tank now that it is taken down to bare metal inside and out. Create and weld in patch for access hole.

Apply metal prep such as Hirsh's tank etch to inside of tank. Follow product instructions.

Apply tank sealer per instructions. See my original post for opinions/reasons for using RedKote tank sealer.

Some people use muriatic acid to nix their tank rust but this is very destructive as it eats metal. If the chemical reaction isn't neutralized it could continue to eat things or rust out the tank. The way to be absolutely sure that the rust is gone is outlined above. Make sure that you focus on the seams and any areas which harbor rust when sandblasting. Ospho gets the rest but needs for there to be as little rust as possible for maximum effectiveness.

Schew!!! That was a longgg post. Sorry.

Beandip, you're absolutley right about the need for extreme caution/safety. Thanks

Jim

Attachments are post tank cleaning/electrolysis. Single "L" shaped electrode was used inside tank. Note how more rust was removed in areas closer to the electrode.