Needing recommendations of products, process for cleaning out stank tank

Anyone with experience cleaning out an old gas tank that once held fuel and has now basically turned into a can of old varnish?

What products, commercial or home brew, have you found to work best, and process of cleaning that's been most effective for you?

Getting ready to clean up the fuel system to fire up the ol' 289 in the Galaxie to get an idea of it's overall condition before pulling it to make way for the 460.

I guess I let the poor girl sit too long since I last worked on her

 

A friend of mine and I just resurrected a '70 Jeep j4000 that the inside of the tank was like how you describe. We used mineral spirits from a local hardware store and a chain. Pour in a gallon drop the chain in shook it for a few mins, let sit, shook again. The junk inside turns into a tar like ball that can be removed easily.

 

I've heard of the chain technique.

Do you need to rinse it out/blow it out or anything afterward, or is gas good to go in once the mineral spirits are poured out and the chain and "tar ball" removed?

 

You need to let the mineral spirits dry after draining it out no rinsing, at least thats what we did. I should also explain "let sit" takes a day or 2 depending on how dirty the tank is. Come to think of it, it may have been acetone, I'll call my buddy later and find out for sure.

 

Had an old 2-stroke fishing boat motor that was stored for 20 years with a full tank. After spooning out syrup the best we could we used a steam cleaner to remove the remains. It took a while but the steam did the job

 

Called my friend yesterday, it was acetone.