Why do we change our engine oil?
Practical Boat Owner|Summer 2022
PBO's engine whisperer Stu Davies ponders the not-so-silly question
Stu Davies
Why do we change our engine oil?

Why do we change our engine oil? A seemingly innocuous question I was asked a few months ago.

Because we do? Because its dirty? Because the handbook says so? It got me to thinking and to do some research because it's not such a silly question!

Oil in our engine is there to lubricate, to prevent our engines from wearing, to cool it. Basically the moving parts of the engine 'float' on a thin film of oil which is pumped around the engine by a pump from the sump. This oil is also sprayed on the underside of the pistons to help cool them and to lubricate the piston rings and where they come into contact with the cylinder walls. To do all these things it has to remain stable under extreme pressure in the bearing areas, and it is also used in some engines to cool them. It also has to be able to negate acidic combustion products.

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Esta historia es de la edición Summer 2022 de Practical Boat Owner.

Comience su prueba gratuita de Magzter GOLD de 7 días para acceder a miles de historias premium seleccionadas y a más de 9,000 revistas y periódicos.

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