Description
- Unlike four-stroke engine whose crankcase is closed except for its ventilation system, two-stroke engines use the crankcase as part of the induction tract, and therefore, oil must be mixed with gasoline to be distributed throughout the engine for lubrication.[1] The resultant mix is referred to as petroil.[2] This oil is ultimately burned along with the fuel as a total-loss oiling system. This results in increased exhaust emissions, sometimes with greyish-blue smoke and/or a distinctive odor.
