I was recently donated a couple of jerrycans, as long as I gave a promise to burn off the water-contaminated fuel inside on my (large) property in a safe manner. No worries there, but I wonder what I can use to treat the cans afterwards? My first thought was seafoam. Any ideas?

 

If they are made of steal, water can rust them out. I used seafoam in my truck last month. It had sat for almost a year and had white residue in the tank. It clogged the pump twice. After the treatment I have had no problems.

 

Rather pricey but could give it a good spray with break clean, then flush again with gas.