I have a Ryobi 77 and for some reason it spits fuel out of the breather hole in the fuel tank cap????The engine runs fine...could it be a worn piston or ring???or maybe a leaking needle and seat????im confused

ryobimad, June 2013

It may be that the gas tank is overheating. When you heat up gas, it expand significantly. It also emit more fumes that are a real fire hasard.

Check the air flow around the engine.

A worn piston can't force air, or anything, back to the fuel tank. If it leaks, you loose power, contaminate the oil with unburnt and partialy burnt gas.

Electro, June 2013