CONTROL GP-ENGINE MONITORING 1176596 - Caterpillar

Illustration 1 g00576312
Torque Converter Hydraulic System (1) Oil filter (2) Pitot tube (3) Lockup clutch selector valve (4) Reducing valve (5) Selector and pressure valve body (6) Speed selection spool (7) Modulation relief valve (8) Load piston (9) Pressure differential valve (10) Ratio valve for torque converter (11) Direction selection spool (12) Oil pump (13) Torque converter (14) Reservoir (15) Screens (16) Oil cooler (17) Relief valve for converter outlet (A) Torque converter scavenge section (B) Transmission charging sectionThe hydraulic system for the torque converter uses a two-section oil pump (12). The pump operates only when the engine is running. The torque converter scavenge section (A) takes oil from the torque converter housing. The torque converter scavenge section (A) then sends the oil to the reservoir (14). The transmission charging section (B) takes oil from the reservoir (14). The transmission charging section (B) then sends the oil to the oil filter (1) .From the oil filter (1), the oil is then sent to the selector and pressure valve body (5) and the reducing valve (4). The pitot tube (2), the lockup clutch selector valve (3), the reducing valve (4) and the load piston (8) control the lockup clutch in the torque converter (13) .The ratio valve (10) inside the selector and pressure valve body (5) controls the inlet pressure to the torque converter (13). From the torque converter, the oil then flows through the torque converter outlet relief valve (17) .From torque converter outlet relief valve (17), the oil flows through the oil cooler (16). From the oil cooler (16), the oil then flows in order to cool the transmission. The oil also flows in order to lubricate the transmission.