Oil Pumps

The oil pump supplies pressurized oil to bearings, the turbocharger, timing components and piston cooling jets. Worn pumps cause low oil pressure, particularly at idle when oil is hot, which accelerates bearing and turbocharger wear.

Pumps may be gear or rotor (gerotor) types, crankshaft-driven at the timing cover or chain-driven in the sump, and some newer engines use variable-displacement pumps. Specify by engine code, drive type, pressure relief valve design and pickup tube configuration. On some diesel engines the oil pump also drives a balance shaft or vacuum pump. Replacing a pump without addressing contaminated oil and a blocked pickup screen rarely solves low pressure. Related: engine overhaul kits.