No matter how tightly within the prescribed specifications an engine's piston clearance and ring tension are in its cylinders, a certain amount of fuel and combustion vapor slips past and enters the ...

Every engine, regardless of its condition, has a certain amount of blow-by or air/fuel mixture that slips past the pistons and rings and finds its way into the crankcase. In addition, during normal ...

Every engine has some sort of crankcase breathing system. The internal combustion process creates pressure, some of which makes its way past the piston rings-along with fuel vapors-and into the rest ...