PLATE 1772495 - Caterpillar

Illustration 1 g00643773
(1) "Torque Converter Scavenge Pump" section
(2) "Torque Converter Charging Pump" section
(3) "Parking Brake Release Pump" section
(4) Cover for the "Torque Converter Scavenge Screen"The pump has three sections:
"Torque Converter Scavenge Pump" section (1)
" Torque Converter Charging Pump" section (2)
" Parking Brake Release Pump" section (3)The pump is driven by a gear on the "Torque Converter".The "Torque Converter Scavenge Pump" section (1) is on the drive end. This pump section takes oil from the bottom of the "Torque Converter" housing. The oil flows through the scavenge screen that is behind cover (4). The oil is then returned to the hydraulic tank.The other two pump sections get oil from the hydraulic tank.The "Torque Converter Charging" section (2) sends the oil to the "Torque Converter Charging Oil Filter", to the "Torque Converter Inlet Relief Valve", and to the "Torque Converter".The "Parking Brake Release" section (3) sends oil to the "Parking Brake Release Oil Filter". The oil flow is then divided. The "Parking and Secondary Brake Valve" receives some of the oil. This oil is used to release to the spring-applied parking brakes. The rest of the oil that is divided flows to the "Lockup Clutch" and to the "Hoist Control Valve". This oil is used to engage the "Lockup Clutch" in the "Torque Converter". The oil that is sent to the "Hoist Control Valve" is used as signal oil.