How do I clean a small engine gas tank?
 

My edger sat so long it gummed up. A new carb was cheap so I ordered a new one. The gas tank was $75 so I'm cleaning it.

It has black stuff, gunk and slight rust in it. How can I clean it out? Throw some chain or nuts/bolts with water and shake it up?

Ideas?

I would think that you would need a solvent like acetone rather than water.

Acetone or lacquer thinner first then follow with nuts bolts in Kerosene or diesel.

i've had good luck with white vinegar and some dish detergent. it gets all the rust, if you let it sit for a day or so. then the nuts and bolts with kerosene.

Lye will do it. For vespas the SOP is a piece of chain, duct tape the entire thing shut, wrap in a towel, duct tape that, then tumble in a dryer for a couple of hours. You can rinse with water, as long as you get the water out of the nooks and crannies with some wd40.

Good ideas. Thanks.

My neibour duck taped a lawnmower tank to the inside of my electric cement mixer with a couple nuts and washers inside. Put the drive belt on the slowest setting and let it spin for a couple of hours.