For 1990-2009 cars

Engine lubrication is supplied by a gear-type oil pump. The oil pump is driven by an intermediate shaft. The intermediate shaft is connected to a driveshaft assembly which is driven by the camshaft. The oil pump gears rotate and draw oil from the oil pan sump through an oil pump screen and pipe. The oil is pressurized as it passes through the oil pump and sent through the engine block oil galleries.

Contained within the oil pump is a pressure relief valve that maintains oil pressure within a specified range.

Pressurized oil is directed to the oil filter where harmful contaminants are removed. A bypass valve is also incorporated into the oil filter. The bypass allows oil to bypass the filter and flow to the engine assembly if the filter becomes clogged.

The oil is then pumped to the main oil gallery which is drilled through the length of the engine block just above the camshaft. at the rear of the engine block, oil also flows into the right and left valve lifter oil galleries. From the main oil gallery, oil is pumped downward to the camshaft bearings, then to the crankshaft bearings. The crankshaft bearing upper inserts are grooved to align with oil passages drilled from the crankshaft bearing journal to the connecting rod journal. After lubricating the connecting rod bearings, the cylinder walls, ring and piston pins are lubricated by oil which is "slung" from the connecting rod bearing journals due to the rotation of the crankshaft. This oil then returns to the oil pan sump. Oil that has entered the left and right valve lifter oil galleries pressurizes the hydraulic valve lifters and is then pumped up through the valve pushrods to lubricate the valve rocker arms and valve stems.

Oil returning to the oil pan from the cylinder heads and the front camshaft bearing, lubricates the camshaft timing chain and crankshaft and camshaft sprockets.

Figure 1: |

#### Engine Assembly Lubrication - Left Side View

Figure 2: |

#### Engine Assembly Lubrication - Front View

Figure 3: |

#### Engine Assembly Lubrication - Rear Views