IMPELLER 2128184 - Caterpillar

Probable Causes
Low engine oil level
Incorrect viscosity
Contaminated engine oil
Improper circulation of the engine oil
Worn componentsRecommended Repairs
Low Engine Oil Level
Check the oil level. Add oil, as needed.Contaminated Engine Oil
Engine oil that is contaminated with another liquid will cause low engine oil pressure. High engine oil level can be an indication of contamination. Obtain an analysis of the engine oil. Determine the reason for contamination of the engine oil and make the necessary repairs. Change the engine oil and the engine oil filter. For the correct engine oil to use, refer to the engine's Operation and Maintenance Manual.Incorrect Viscosity
Make sure that the engine is supplied with the correct engine oil. For the correct engine oil to use, refer to the engine's Operation and Maintenance Manual.Improper Circulation of the Engine Oil
Several factors could cause improper circulation of the engine oil:
The engine oil filter is clogged. Replace the engine oil filter.
An engine oil line or a passage for engine oil is disconnected or broken.
The engine oil cooler is clogged. Thoroughly clean the engine oil cooler.
There is a problem with a piston cooling jet. Breakage, a restriction, or incorrect installation of a piston cooling jet will cause seizure of the piston.
The inlet screen of the suction tube for the engine oil pump can have a restriction. This restriction will cause cavitation and a loss of engine oil pressure. Check the inlet screen on the suction tube and remove any material that may be restricting engine oil flow.
The suction tube is drawing in air. Check the joints of the tube for cracks or a damaged O-ring seal.
There is a problem with the engine oil pump. Check the gears of the engine oil pump for excessive wear. Engine oil pressure is reduced by gears that have too much wear.
The engine oil pump's pressure regulating valve or a bypass valve is stuck in the open position. Clean the valve. Replace parts, if necessary.Worn Components
Excessive clearance at the crankshaft or camshaft bearings will cause low engine oil pressure. Also, inspect the clearance between the rocker arm shafts and the rocker arms. Check the engine components for excessive clearance.Obtain an analysis of the engine oil. Check the analysis for the level of wear metals in the engine oil.