Lubricating system parts is comprised of oil pumps, valves, dipsticks, oil lines, lube oils and other parts. The lubrication system’s main function is to distribute oil to the moving parts to reduce friction between surfaces. The oil pump drives oil to the top of the engine into the crankcase, onto the pistons, then runs down inside the crankcase to the main bearings. Along the outside of the bottom of the crankcase is a collection tube which gathers up the used oil and returns it to the oil pump to be circulated again. Always Use genuine parts and adequate grade oil to ensure a smooth engine operation.