Tiny's advice is exactly right, I started one after it sat for 30 years on old gas, and it ran great the first time, then I shut it off and a few days later tried to start it up.......BANG!!!! bent several push rods and had all 6 valves stuck. That mistake cost me about $300.00 for a valve job and gasket set, I did the labor myself. Be sure to drain every drop of that old gas out and clean everything thoroughly before running new gas in it. I bought a new tank and fuel lines, rebuilt fuel pump, overhauled caarburetor, now everything's fine.
