What is an Oil Pump?

We all know what a cooling fan is. It is a fan that cools. We also now what a fuel pump is. It's a pump that pumps fuel. So, guess what an oil pump does? It is a pump that pumps Oil.  Woah, the answer to that question was more surprising than the end of a M. Night Shyamalan movie.  Ok, so the oil pump sounds like a pretty basic part, but it plays a vital role in the operation of your vehicle.

The oil pump inside of an internal combustion engine is used to lubricate the engine and reduce friction.  The pump powers oil through bearings, sliding pistons, camshafts, and other small parts. The decrease in friction also means the cooling of pistons, bearings, and shafts. Failure to properly lubricate an engine will result in engine failure.  Now you see how important that cleverly named oil pump is.

The oil pump needs to be generating approximately 10 psi per every 1000 revolutions per minute in order to properly lubricate the system.  If your oil pump is working well but you are still having a low pressure issue, it may be caused by a clogged oil pickup screen, too much wear on a high mileage engine, or you just need to add more oil to your car.  Each car has different oil requirements.  Higher performance vehicles put more stress on the system and they need more lubricating. 

There are basically three types of pumps, a twin gear pump, a Gerotor Pump, and an internal pump.  A twin gear pump has one gear connected to a shaft that is driven by the camshaft or distributor.  A twin gear pump turns at half the speed of the engine and is located inside the oil pan.  A Gerotor Pump has one small gear rotating inside a larger one.  While an internal pump is a Gerotor style pump, an internal pump turns at the same speed of the engine so it creates a stronger flow. An internal pump design is used on overhead cam engines.