TORQUE CONVERTER

The Illustration shows a sectional view of the torque converter. The major components include the rotating housing, the impeller, the turbine, the nonfree wheel stator, the impeller clutch, and the lockup clutch.

The rotating housing is splined to the engine flywheel and turns with the flywheel.

When the impeller clutch port is pressurized, the impeller is connected to the rotating housing through the impeller clutch engagement. The clutch discs are splined to the impeller. The clutch plates are splined to the rotating housing. Pressure oil at the clutch piston will engage the discs and plates. The impeller rotates with the housing.

The turbine is splined to the output shaft. In torque converter drive, the turbine is turned by oil from the impeller.

In direct drive, the lockup clutch port is pressurized. The lockup clutch connects the turbine to the rotating housing. The lockup clutch discs are splined to the turbine. The lockup clutch plates are splined to the rotating housing. Pressure oil moves the clutch piston to engage the discs and plates. When the clutch is engaged, the turbine, the housing, the impeller, and the output shaft rotate as a unit at engine rpm.

Housing

Turbine

Impeller Impeller Clutch Stator

Impeller Clutch Port Lockup Clutch Port Torque Converter Oil Port Clutch Discs Clutch Discs

Impeller Clutch Oil Pressure Converter Oil Output Shaft

TORQUE CONVERTER

Lockup Clutch Oil Lockup Clutch

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Transmission

The basic transmission remains unchanged.

The planetary power shift transmission (1) has three FORWARD and three REVERSE speeds. Electronic solenoids located in the hydraulic control valve (2) shift the transmission. The solenoids are actuated by the Power Train Electronic Control Module (ECM) located in the electronics bay in the platform on the left side of the machine.

The transmission output speed sensors (3) monitors the transmission output shaft. The signal is sent to the Power Train ECM. The transmission output speed signal indicates when the

clutches have engaged and the direction of the ground speed.

The two transmission oil screens located in the front of the output transfer gear housing can be accessed by removing the covers (4).

The oil sump for the transmission pump is located in the bottom of the output transfer gear case (7).

Shown here are the secondary steering pump and diverter valve (5) and the output shaft (6) for the rear drive shaft. The transmission fill tube (8) and the transmission liquid level gauge (9) are also shown.

1 2 4 6 7 3 5 9

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This illustration is a sectional view of the impeller clutch solenoid valve.

When the impeller clutch solenoid is DE-ENERGIZED, the spring moves the pin assembly against the ball. The ball blocks the pump flow through the orifice to drain. The oil pressure increases at the left end of the valve spool and moves the valve spool to the right against the spring. The valve spool blocks the passage between the impeller clutch and drain and opens the passage between the impeller clutch and the pump. Pump oil flows past the valve spool to the impeller clutch.

When the impeller clutch solenoid is ENERGIZED, the solenoid moves the pin assembly against the spring and away from the ball. Pump oil flows through the center of the valve spool, through the orifice and past the ball to drain. The valve spring moves the valve spool to the left. The valve spool blocks the passage between the impeller clutch and the pump and opens the passage between the impeller clutch and drain. Pump flow to the impeller clutch is blocked. The oil in the impeller clutch flows past the valve spool to drain.

From Pump To Impeller Clutch Solenoid Armature Assembly

Ball Orifice _SpoolValve _Spring Spring Test Port IMPELLER CLUTCH SOLENOID DE-ENERGIZED IMPELLER CLUTCH SOLENOID ENERGIZED IMPELLER CLUTCH MODULATING VALVE From Pump To Impeller Clutch Solenoid Armature Assembly

Ball Orifice _SpoolValve _Spring Spring

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This illustration is a sectional view of the lockup clutch solenoid valve.

When the lockup clutch solenoid is DE-ENERGIZED, the force that held the pin assembly against the ball is removed. The pump oil flows through the orifice and past the ball to drain. The spring moves the valve spool to the left. The valve spool opens the passage between the lockup clutch and drain and blocks the passage between the lockup clutch and the pump. Pump flow to the lockup clutch is blocked. The oil in the lockup clutch flows past the valve spool to drain.

When the lockup clutch solenoid is ENERGIZED, the solenoid moves the pin assembly against the ball. The ball blocks pump oil flow through the orifice to drain. The oil pressure increases at the left end of the valve spool and moves the valve spool to the right against the spring. The valve spool blocks the passage between the lockup clutch and drain and opens the passage between the lockup clutch and the pump. Pump oil flows past the valve spool to the lockup clutch. From Pump Solenoid Pin SOLENOID DE-ENERGIZED Test Port From Pump Ball Orifice _SpoolValve _Spring

Solenoid Pin