ELEMENT-FUEL 5134491 - Caterpillar

Demand Fan System
Illustration 1 g03843014
(1) Pump (charge)
(2) Cooler
(3) Motor (demand fan)
(4) Tank (hydraulic)
(5) Filter (hydraulic oil)
Illustration 2 g03843349
(1) Motor (demand fan) Hydraulic oil for the motor (demand fan) (1) is supplied by the pump (charge) (2). Hydraulic oil from the tank (hydraulic) (3) flows to the front section of the pump (implement). The oil flows from the pump (charge) (2) to the motor (demand fan) (1). The flow of oil through the gear motor turns the fan that cools the hydraulic oil that passes through the cooler (4).The fan motor will rotate in direct relation to the amount of hydraulic oil flow until the hydraulic oil pressure reaches the setting for the relief valve (electrohydraulic proportional) . The relief valve (electrohydraulic proportional) allows the excess oil to bypass the gear motor. The relief valve (electrohydraulic proportional) is not a mechanical type of valve. The relief valve (electrohydraulic proportional) is controlled by the ECM based on input by the engine coolant temperature sensor and the hydraulic oil temperature sensor. Use the Caterpillar Electronic Technician software in order to calibrate the demand fan. For more information on the calibration of the demand fan, refer to Hydraulic System Testing and Adjusting, "Gear Motor (fan) - Test".Reversing if Equipped
Illustration 3 g03839928
(1) Reversing fan configuration (if equipped)
(1) Reversing fan
(2) Check valve
(3) Relief valve
(4) Reversing solenoid
(5) Gear motor Hydraulic oil for reversing fan (1) is supplied by the charge pump. The oil flows from the charge pump to motor (1). The flow of oil through the gear motor (5) turns the fan that cools the hydraulic oil that passes through the hydraulic oil cooler.The fan motor will rotate in direct relation to the flow of hydraulic oil until the hydraulic oil pressure reaches the relief valve (3) setting. Relief valve (3) allows the excess oil to bypass the gear motor (5). Relief valve (3) is a mechanical type of valve.The fan will operate normally until reversing solenoid valve (4) is activated. This action will reverse the rotation of gear motor (5).There are three modes for reversing fan (1) to function, all are controlled by a switch in the cab.
Off (normal demand fan operation) Switch CENTER position
Automatic (this mode sets the fan to reverse at set intervals and duration set in ET) Switch UP position
Manual override (this is a momentary switch that allows the operator to force a set cycle to occur) Switch is pressed down and releasedNote: Once a manual override is completed the operator must place the switch back in the auto mode.