TM-9-2815-220-34 Direct Support Manual for AVDS-1790-2C and AVDS-1790-2D Engines Download
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-... TM 9-2815-220-34 pressurized oil is forced through the engine oil coolers and oil filter to the engine oil galleries, bearings, turbosuperchargers, fuel injection pump and to the piston oil sprayer nozzles. These nozzles are located in the crankcase below each cylinder and provide a continuous oil spray to the pistons and cylinder walls. A pressure regulator valve, lo- cated on the dght side of the crankshaft damper and oil filter housing is innuenced by the pressure in the main bearing oil gallery and returns the incoming excess unfiltered oil to the oil pan. b. Oil Pn. The oil pan (fig. 1-1) is a one-piece aluminum alloy casting divided into a pressure oil / pump compartment, oil reserve compartment, and the sump compartment at. the frortt of the pan. Cored passages from each of the compartments terminate at a central outlet and permits draining all of the compartments from a single drainage point. A cored passage also permits draining the oil coolers and oil filter compartment directly without permitting any sludge to enter the oil pan. The oil pan is designed to maintain a constant oil level above the main pressure oil pump pickup tube jn the pressure oil pump compartment during vehicle operation regardless of the angle at which the en- gine may be inclined. TA 126084 I Figure 1-9. Erigi+e lubrication &y&tem. c. Oil Pump. The oil pump assembly consists of four sections combined as a single unit. The scavenge oil pump section of the unit picks up oil from the front end compartment of the oil pan and delivers it to the main pressure pump oil compart- ment. The main pressure oil pump section picks up oil from its respective compartment and supplies oil to the engine oil galleries, bearings, and to the piston oil sprayer nozzles. The level in the pressure pump compartment is maintained by a dual inlet leveling pump which retus any excess oil to the resefve compartment: Oil is pumped from the re- serve compartment by two make up pumps in a single pump section. These pumps pick up oil from 1-14 Change 2 opposite corners of the reserve compartment and discharge it into the pressure pump compartment. The dual pump design insures return of oil from the reserve compartment under all operating con- ditions, cold oil, slope operation, etc. d. Oil Filters and Control Valves. The engine oil filters (fig. 1-3) and the bypass valve are located in the crankshaft damper and oil filter housing at the front of the engine. All engine oil passes through the oil filters. The oil filter bypass valve opens at a differential pressure of 35.6 psi. The bypass valve permits oil to bypass the filters in the event that they become clogged.