ROD AS-YM 3935218 - Caterpillar

Illustration 1 g00498105
Power Train Hydraulic System Schematic (1) Hydraulic Control Mechanism for Left Brake (2) Oil Filter (3) Oil Pump (Two Sections) (4) Hydraulic Control Valve For Steering Clutches (5) Oil Cooler (6) Hydraulic Control Mechanism for Right Brake (7) Transmission Case (8) Reservoir in Steering Clutch and Bevel Gear Case (9) Transmission Lubrication Valve (10) Magnetic Screen (11) Flywheel Clutch and Drive Train Control Valve (12) Flywheel Clutch Housing (A) Transmission Oil Pump (B) Left Steering Clutch Piston (C) Right Steering Clutch Piston (D) Left Brake Booster (E) Right Brake Booster (F) Transmission Lubrication (G) Transmission Oil PumpIntroduction
The hydraulic system has a common reservoir. This system gives lubrication oil for the bevel gear, the pinion and the transmission. The system sends cooling oil to the flywheel clutch, the steering clutches and the brakes. The system also gives pressure oil for the operation of the hydraulics controls for the steering clutch, the brakes and the flywheel clutch.Operation
Oil pump (3) pulls oil from the reservoir (8) through the magnetic screen (10). The pressure oil that circulates through the sections is sent to the oil filter (2). If the oil filter has restrictions, a bypass valve in the filter allows the oil to pass around the filter.At the oil filter, the oil flow is divided. One path goes to the steering clutch valve. The second path goes to the hydraulic clutch. Oil then goes to the drive train brake control valve (11). Pressure for the steering clutch controls is obtained by the setting of a relief valve. The valve is located at the flywheel clutch and the drive train brake control valve.The steering clutch and brake control valve supplies pressure oil to the steering clutch and the brake. The valve also supplies pressure oil for lubrication. Oil is then returned to the case sump.Oil from the filter is directed to the flywheel clutch and drive train brake control valve. At the control valve, a priority valve ensures that the steering and brake control valve and the drive train brake control valve get oil before the clutch control valve. Oil flow that travels through the clutch and drive train brake control valve is also sent to the clutch to lubrication.The drive train brake is operated by pressure oil that is sent from the clutch and the drive train control valve. Oil that leaks from the clutch and the drive train control valve is routed to the drive train brake for lubrication.Oil in the clutch sump is pulled through a magnetic screen (10) by the scavenge section of the transmission sump.The scavenge section of the pump provides oil to the cooler. After the oil is made cool by the oil cooler, the oil is sent to the transmission lubrication valve (9). Valve (9) limits the pressure of the lubricating oil. Valve (9) also directs excess oil to the transmission sump.