Engine Lubrication

Lubrication: the process of making machinery smooth and easy to work by putting oil, grease, etc on the parts.

The role of the lubrication system of a small gas engine is make sure that all moving parts receive lubrication or oil. The piston, moving up and down in the cylinder, must be lubricated to make sure that it can move up and down very easily in the cylinder. All moving part must receive lubrication, or the engine will not work.

Types and Purpose of the Lubrication System

The oil is stored in the bottom of the crankcase, and oil is splashed by the oil dipper up onto the moving parts.

A. Types of Lubricating Systems

1) Splash - dipper on connecting rod cap. This is the type of lubrication system our small gas engine had.
2) Pressure feed - oil is forced by an oil pump. This is the type of lubrication systems that most cars have.
3) Combination of a splash and pressure feed.

B. Purpose of lubricating system

The lubricating oil must -

1) Lubricate moving parts to minimize wear.
2) Lubricate moving parts to minimize power loss from friction.
3) Remove heat from engine parts by acting as a cooling agent.
4) Absorb shocks between bearing and other engine parts, thus reducing engine noise and extending engine life.
5) Form a good seal between piston rings and cylinder walls.
6) Acts as a cleaning agent.


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