CRANKSHAFT AS 3542977 - Caterpillar

Illustration 1 g00776853
Location of the pump for the torque converter, parking brake release, and brake cooling
(1) Torque converter scavenge section
(2) Torque converter charging section
(3) Torque converter and parking brake release section
(4) Front brake cooling section
(5) Cover for the torque converter scavenge screen The following four sections are included in this pump.
Torque converter scavenge section (1)
Torque converter charging section (2)
Torque converter and parking brake release section (3)
Front brake cooling section (4)The pump is driven by a gear on the torque converter.Torque converter scavenge section (1) is located on the drive end. This pump section takes oil from the bottom of the torque converter housing. The oil flows through the scavenge screen behind cover (5). The oil is then returned to the hydraulic tank.The other three pump sections (2), (3), and (4) get oil from the hydraulic tank. The inlet side of the torque converter charging section (2) and the inlet side of the parking brake release section (3) are connected.Torque converter charging section (2) sends the oil to the torque converter oil filter, to the torque converter inlet relief valve, and to the torque converter.The torque converter and parking brake release section (3) sends oil to the parking brake release oil filter. This oil flow is then divided. Some of the oil flows to the parking and secondary brake valve. This oil is used to release the spring applied parking brakes. The rest of the oil that was divided flows to the lockup clutch and synchronizing valve. This oil is used to engage the lockup clutch in the torque converter.Front brake cooling section (4) sends oil to the torque converter and front brake cooling screen. The oil combines with oil from the torque converter outlet relief valve. This oil and the oil from the torque converter are sent through one of two diverter valves.At the diverter valve, one of two actions can occur. If the front brakes are applied, the diverter valve sends the oil through the oil cooler in order to cool the oil before going to the front brakes. If the brakes are not applied, the oil goes directly to the brakes. After cooling the front brakes, the oil returns to the hydraulic tank.