Those of you that have been around mowers long enough to see such a thing...
I was given a Rover mower with a Briggs & Stratton Sprint 375 engine. It was given to them too and they thought it had blown the head gasket, and claimed it was "leaking oil or fuel". They even warned me to bring some cardboard to stop the oil leaking in our car. It did have a little oil on the deck, but that could have just been someone spilling oil during an oil change. A half hour drive home left no oil leaks in the car.
So I pulled the sparkplug and gave the cord a light pull. Spark ok. The crankcase was still full of oil, so I put some fresh fuel in, primed, and gave it a pull... It started and ran great. No smoke, ran smooth... So I degreased it in case it did have an oil leak (knowing I'd see any fresh oil on a clean deck). But nope, still no leak.
Then I pulled the fuel tank off and noticed oil leaking from the crankcase gasket, and about an inch of the gasket was hanging out... Like it had either been blown outwards by force due to some fault, or, was not fitted correctly in the first place when the engine was being bolted together at the factory.
My question is... Is there an engine fault that could cause the crankcase gasket to blow out? I'm concerned if I replace the crankcase gasket, it could blow out again (if that's even possible/likely?).
