dirty gas tank from old gas

[phase_one]

Wasn't sure where to post. I know this board has the most traffic so someone should see and can help. I bought an 92 chevy van for the engine and trans. Of course not all is prestine. The van had been sitting for 4 years. The tank has what used to be gas in it. I use a siphron pump to get the gas out and then dropped it. There is a ton of the tar/varnish in it. How do I get it out? The exterior of the tank is good. I changed the fuel fitler and blew out the fuel lines with my air compresser. I have a new fuel pump and sending unit to install. Just looking for the best way to clean out the gunk. Any help would be good. By the way to tie this to the 67-72 section this will all go in my 70 when all is running.

[Eddie H.]

Go to the local Home Depot/Lowes, etc and get a gallon of lacquer thinner
Pour that in the tank and slosh it around awhile, that will probably dissolve most of the old varnish and junk in the tank. Just be sure you do it outside, because the fumes will be highly toxic, as well as flammable.
Another option is to use carb cleaner like Berrymans B12, but it is more expensive.

[cdowns]

home depot lowes harbor frieght all have biodegradeable degreasers that mix with water and are non explosive and safe to use put a couple of handfulls of large bolts in the tank and the degreaser mixed with a couple of gallons of water slosh it around real good rince with water run air hose in tank to get rid of any moisture

[dingo_dan_22]

I took my gas tank to a rad shop. They cleaned it out and coated the tank for $40 bucks.

[67CHIP72]

Originally Posted by dingo_dan_22

I took my gas tank to a rad shop. They cleaned it out and coated the tank for $40 bucks.

Cleanest route I would recommend.

[phase_one]

That sounds like a good investment.