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How an Engine Lubrication System Works

Engine Lubrication System Components

Let's follow Oliver the Oil Molecule on his journey around the engine!

Oil pan: This is where Oliver hangs out when the engine isn't doing anything; the oil lounge, if you will. In most cars, this pan holds about 4 to 6 quarts of oil.

Pickup tube: When the engine is switched on, it needs oil immediately. Oliver and his oil buddies get sucked up by the pickup tube and lined up for action.

Oil pump: The pump does the sucking so that Oliver can slide up that tube against gravity and then pressurizes the oil. Oliver and his little oil friends get jammed in together even closer. Let's hope Oliver remembered to put on deodorant today.

Pressure relief valve: If Oliver and his friends get too close they start to plan a riot, this relief valve gives them a bit of much-needed breathing space. It's the lubrication system's way of saying, "Settle down, kids."

Oil filter: While Oliver and his friends are allowed to pass into the engine, the filter stops any dirt and debris the oil may have picked up on its last pass through the system.

Spurt holes and galleries: Oliver giggles every time he says "spurt holes." He's really immature. These are the little holes drilled in the crankshaft or other parts of the system that allow the oil to coat the bearings and cylinders that need to stay lubricated.

Sump: After doing his job to keep the moving parts of the engine moving, an exhausted Oliver slides all the way down into the oil pan again, also known as the sump, to hang out until he's sucked back up the pickup tube -- and he's back on the job.