TURBOCHARGER GP 2106945 - Caterpillar

Illustration 1 g00395468
Lockup clutch and synchronizing valve (1) Lockup clutch solenoid (2) Passage from the transmission charging pump section (3) Signal oil passage (4) Pilot oil passage (5) Lubrication passage for transmission (6) Relay valve (7) Spool (8) Spring (9) Cover (10) Load piston body (11) Selector piston (12) Load piston (13) Pilot oil passage (14) Springs (15) Drain passage (16) Modulation reduction valve (17) Ball check valve (18) Shuttle valve (19) Pilot oil passage (20) Drain passage (21) Spring (22) Passage (23) Drain passage (24) Load piston plug (25) Load piston orifice (26) Pump oil passage (27) Ball check valve (28) Drain passage (29) Pressure reduction valve (30) Spring (31) Body of the lockup clutch and synchronizing valve (32) Passage to lockup clutch (33) Passage from parking brake release pump section (34) Drain passage (35) Passage to the selector and pressure control valve
Illustration 2 g00486101
Lockup clutch and synchronizing valve (3) Signal oil passage from the lockup clutch solenoid (5) Lubrication passage for transmission (6) Relay valve (31) Body of lockup clutch and synchronizing valve (33) Passage from parking brake release pump sectionThe Electronic Programmable Transmission Control (EPTC II) will energize the lockup clutch solenoid when direct drive is necessary. During direct drive, the engine is mechanically connected to the transmission by the activation of the lockup clutch. When direct drive is not necessary, the lockup clutch solenoid will be deactivated. The machine will then be in torque converter drive. The engine will be hydraulically connected to the transmission.When EPTC II sends a signal to lockup solenoid (1) to activate, the solenoid will allow transmission oil to flow from passage (2) to passage (3). Signal oil will flow through passage (3) to relay valve (6). The signal oil in passage (3) causes spool (7) to act against spring (8). Passage (4) is now open to passage (19) and pilot oil will flow to selector piston (11). Some of the transmission oil in passage (3) flows into passage (5) for transmission lubrication.When EPTC II sends the signal to deactivate, the solenoid will stop flow to passage (3). Spring (8) will push spool (7) back to the original position. As a result, torque converter oil to passage (19) is blocked. When the solenoid is deactivated, signal oil will flow from passage (5) into passage (3). This keeps passage (3) full of oil so that there is no delay when the solenoid is activated. Pressure from passage (5) is not enough to move spool (7) .The lockup clutch solenoid valve controls the operation of the lockup clutch and synchronizing valve of the torque converter. Pressure oil in outlet line (32) engages the lockup clutch. This oil comes from the parking brake release pump section. The oil splits at the parking and secondary brake valve. Some of the oil goes through inlet line (33) into valve body (31). The remaining oil goes into the parking and secondary brake valve.Pressure oil from the parking brake release pump enters the body of lockup clutch and synchronizing