removing varnish from fuel tank

[85GPLef41]

I found a guy parting out a 87 T-type today on craigslist. Called him up on the fuel tank for my LS1 Swap, I also tried to get the 8.5 10 bolt but he had sold it earlier this morning...Anyways I pulled the tank for my swap but it didn't have the sending unit, the hole was covered though and after looking inside carefully it it only has a varnish build up on the bottom from the old gas. Now i did a bit of research and found a variety of ways to get it out ie: acetone, chains or gravel in the tank and shaking it,getting it boiled out at a radiator shop etc etc. The varnish doesn't seem to be stuck in on the metal portions i tried spraying a bit of brake clean and it broke it up the varnish on the plastic baffles though. I don't want to damage the baffles and it doesn't have any rust inside or out. It has about a half gallon of the old gas how would you guys get it out and cleaned?? ANY IDEAS??

 

[bill]

I found a guy parting out a 87 T-type today on craigslist. Called him up on the fuel tank for my LS1 Swap, I also tried to get the 8.5 10 bolt but he had sold it earlier this morning...Anyways I pulled the tank for my swap but it didn't have the sending unit, the hole was covered though and after looking inside carefully it it only has a varnish build up on the bottom from the old gas. Now i did a bit of research and found a variety of ways to get it out ie: acetone, chains or gravel in the tank and shaking it,getting it boiled out at a radiator shop etc etc. The varnish doesn't seem to be stuck in on the metal portions i tried spraying a bit of brake clean and it broke it up the varnish on the plastic baffles though. I don't want to damage the baffles and it doesn't have any rust inside or out. It has about a half gallon of the old gas how would you guys get it out and cleaned?? ANY IDEAS??

I would drain the old gas....add some seafoam (3-4oz) and about a gallon of good clean premium gas (preferably non ethanol)...seal it up and let it soak for a few days....shake it once in a while to move it around....then drain it out. Good gas and seafoam will break it down and liquify it and allow it to drain out. I have heard that setting an unsealed tank out in the cold (below 20f) for a day or so will make the varnish become brittle and flake off....but never tried it...doesnt get that cold here.

 

[85GPLef41]

I would drain the old gas....add some seafoam (3-4oz) and about a gallon of good clean premium gas (preferably non ethanol)...seal it up and let it soak for a few days....shake it once in a while to move it around....then drain it out. Good gas and seafoam will break it down and liquify it and allow it to drain out. I have heard that setting an unsealed tank out in the cold (below 20f) for a day or so will make the varnish become brittle and flake off....but never tried it...doesnt get that cold here.[/quote]

Thanks i'm going to give it a try..Lucky you it hasn't been too warm lately here sun is out but cold, that and i'm getting over a cold... :| I tried draining out the old gas but now matter which way i turned it over it wouldn't come out either from the fule pump hole or the filler neck.. I'm going to try to suck it out with a vacuum pump..

 

[cutlassguy]

i too have done "the gas tank grind and hump" lol you can get most of it out the filler tube, but theres always that last little bit that stays in there boogie on man!!

 

[85GPLef41]

I picked up a vacuum pump from MAC tools that i plan on using now! I'm going to go buy the seafoam tomorrow and celan it out will post before and after pics.. Whenever i get it done.