Cleaning a fuel tank

[Craig Burriss]

I’ve been slowly working on my ‘71 D100 and it had some gas in it that’s probably older than me. The inside of the tank looks pretty bad. The outside of the tank is perfect. I actually thought it was a new tank when I first saw it, but it’s dated July 1970. I’ve read multiple ways of cleaning out an old rusty fuel tank. What have y’all done? And how did it work?
I plan on eventually going to a rear mounted fuel cell, so I don’t want to spend a ton of money and effort on this tank. Just want to get it drivable for now.

Thanks!

 

[Dfr360cuda]

Take it to a radiator shop.

 

[Dartndude73]

For what it's worth. I've used a 50/50 mix of vinegar and water on motorcycle tanks that were rusted like that. After power washing the inside best I could. I would fill the tank. I added a bunch of old nuts and bolts. Let it sit for 4 or 5 days shaking it every time I got a chance. They have always cleaned up really nice. I used a tank coat after. A little tougher on a truck tank.lol

 

[ch1ll]

I would get a plastic tank out of a 73 and up pickup out of the junkyard and get rid of the tank behind your seat. You’ll be much happier and have more leg room.

 

[Bodyperson]

My friend agitated his tank by attaching it to a cement mixer.

 

[1MeanA]

I just used MEK which cleaned the brown varnish nicely. Rust will need something different.

 

[plymouth4onthefloor]

if there is a new gas tank for a fair price, go that way.
Cleaning: i took last time citron acid with hot water. Had really bad old fuel **** in my motorcycle gas tank. Next step was Evaporust. Then you have to protect the gas tank inside.