I shouldn’t grumble that someone used pump gasoline in their Coleman 222A, because I bought it cheaply as ‘not working’. Also, the check (non-return) valve was stuck closed with the same deposits. The little steel ball in it is now freed from the tarry mess and the interior of the tank is soaking in solvent. The generator is clean, suggesting that its predecessor failed and was replaced but to no avail, since the fuel pickup tube and check valve had already stopped working by then. No way to treat a lantern! John
@Fireexit1 Thank you Chris … parts are responding well to the acetone and auto transmission fluid mixture soak!
Got it running well, in the Action Gallery HERE. A solvent (acetone) soak did most of the work … … and running a high ‘E’ guitar string (0.23mm diameter) through the fuel pickup once the gum blocking it had been softened was crucial. Success!