GUN-AIR 4415255 - Caterpillar

Illustration 1 g01361301
(1) Piston cooling jets
(2) Camshaft journals
(3) Main bearings
(4) Oil passage
(5) Turbocharger oil supply line
(6) Oil filter bypass valve
(7) Oil filter
(8) Oil cooler bypass valve
(9) High pressure bypass valve
(10) Oil Cooler
(11) Engine oil pump
(12) Oil pump bypass valve
(13) Secondary engine oil filter (if equipped)
(14) Engine oil pan The lubrication system supplies filtered oil at approximately 275 kPa (40 psi) at rated engine operating conditions. Oil pump bypass valve (12) is controlled by the engine oil manifold pressure.Oil cooler bypass valve (8) maintains the engine oil temperature to 110 °C (230 °F). High pressure bypass valve (9), which is located in the filter base, protects the filters and other components during cold starts. The opening pressure of the High pressure bypass valve is 695 kPa (100 psi). Secondary oil filter (13) is a five micron filter which filters five percent of the oil flow before returning the oil to the sump. The pressure differential of the oil filter bypass valve is 170 kPa (25 psi). The engine oil pressure sensor is part of the engine protection system.The turbocharger cartridge bearings are lubricated by oil supply line (5) from the main oil gallery, and the oil drain line returns the oil flow to the sump. Oil Flow Through The Lubrication System
Illustration 2 g01361302
Oil flow through engine
(15) Oil flow to the piston, piston cooling jets, valve mechanism, camshaft journals, crankshaft main bearings, and the turbocharger
(16) Main oil gallery in cylinder block
(17) Oil drains to sump
(18) Cylinder block
(19) Oil from engine oil cooler
(20) High pressure relief valve
(21) Oil from engine oil pump
(22) Oil to engine oil cooler
(23) Passage to primary engine oil filter
(24) Filtered oil
(25) Bypassed oil
(26) Oil filter bypass valve
(27) Passage to primary engine oil filter
(28) Oil cooler bypass valve
(29) Oil pump bypass valve
(30) Oil pump bypass drain
(31) Passages to secondary oil filter The engine oil pump is mounted to the back of the front gear train. The engine oil pump is driven by an idler gear from the crankshaft gear. Oil is pulled from the sump through the oil pump on the way to the engine oil cooler. The bypass valve controls the engine oil pressure. The engine oil pump is capable of supplying excess oil for the lubricating system. When this situation is present, the oil pressure increases and the bypass valve opens. The open bypass valve allows the excess oil to return to the sump. High pressure relief valve (20) regulates high pressure in the system. The high pressure relief valve will allow the oil to return to the sump when the oil pressure reaches 695 kPa (100 psi).Note: The high pressure relief valve is used as additional protection in case the oil bypass valve can not reduce the oil pressure.The oil then flows through the engine oil cooler. The engine oil cooler uses engine coolant in order to cool the oil. The oil cooler bypass valve (26) directs the oil flow through the engine oil cooler according to the temperature of the oil and the pressure of the