Model 10324 with 2 stroke Duraforce engine. Head gasket was leaking. Engine ran fine, only symptoms were a little harder to start and I could hear a wheeze when pulling the starter rope. I rebuilt this engine about 6 years ago and estimate more than 250 hours on it since the rebuild. Fed a regular diet of pump gas and 32:1 Mobil One 2T until I switched to Castrol RS TTS about 2 years ago, also 1 oz of Seafoam/gal. Is the cleanliness of head due to the engine's diet or the result of the gasket leak? Maybe this is normal but I was a little shocked.