cleaning out the fuel tank and fill tube

Definitely clean it or replace it! I only drove mine about a 1/4 mile home off of the transport and removed the tank and cleaned it out. Too late, that old gas in the fuel line got in the engine and stuck a valve which bent the push rod. Luckily, pouring some lacquer thinner on the valve stem got it loose, $3.00 for a push rod, and an oil change fixed the problem. I cleaned the tank with lacquer thinner to get the varnish out then Evapo-Rust to attack the rust. I put a log chain in the tank both times and rattled it around inside the tank to help break loose the flaky stuff. I am not keen on most of the coatings on the market because many of them are attacked by the alcohol in the rotten gasoline we get today. I know of lots of horror stories about the coatings breaking down; then you have a real mess. If your tank is thin or full of pin holes, take it to Gas Tank Renu ($300) or replace it. Hope this helps. Scott