HOUSING AS-CENTER 1248288 - Caterpillar

Torque Converter
The information that follows can be used to diagnose problems in the torque converter. This information does not list every possible problem. The problem could be in the engine or the transmission.ProblemThe torque converter gets hot.Probable Cause
Bad temperature gauge or sending unit
Long periods of operation with the torque converter at stall speed or near stall speed
Abnormal cooling system operation
Cores in the oil cooler that are not completely open
Restriction in the oil cooler lines
Low oil pressure
Low oil level
Torque converter inlet relief valve that is not operating correctly
Torque converter outlet relief valve that is not closing
Leakage around seals in the torque converter
Air in the oil system
Torque converter scavenge line that is restricted or plugged
Screen in the torque converter housing that is plugged
Mechanical failure in the torque converterProblemThe torque converter inlet pressure is high.Probable Cause
Torque converter inlet relief valve that is not operating correctly
Restrictions in the torque converter outlet relief valve
Restrictions in the outlet line to the oil cooler
Power train oil that is not at normal operating temperatureProblemTorque converter inlet pressure is low.Probable Cause
Inadequate flow from the transmission oil pump
Torque converter inlet relief valve
Dirt or foreign material in the valve
Torque converter outlet relief valve
Weak spring
Dirt or foreign material in the valve
Seal leakage in the torque converterNote: Dirt and/or foreign material in the valves will prevent the valves from closing properly.ProblemThere are noises in the torque converter that have the sound of metal to metal contact.Probable Cause
Bearings with excessive wear or damage
Loose turbine, impeller, or stator blades
Too much side load on the output shaftSteering and Brakes
ProblemThe machine will not turn in one direction.Probable Cause
The steering clutch will not release or the brake will not engage on the side of the unavailable direction.
Contamination in the clutch or brake pilot valve
Spool for the clutch or brake valve that is hanging upProblemThe machine will not turn in either direction.Probable Cause
The steering clutches will not release or the brakes are engaged.
Contamination in the clutch or brake pilot valves
Spool for the clutch or brake valve that is hanging up
Seals on the brake pistons that are leaking
Poppet assembly for the solenoid on the brake valve that is stuck open
Low oil pressure to the steering and brake control valve
Priority valve that is not operating correctly or an incorrect pressure setting
Excessive leakage in the power train oil systemNote: When the oil pressure is low enough, both brakes will engage.ProblemThe machine moves in one direction when the steering control levers are released.Probable Cause
The steering clutch will not engage or the brake is engaged on the side of the turning direction.
Contamination in the pilot valve for the clutch or brake
Spool for the brake that is hanging up
Leaking seal on the clutch or brake piston
Excessive wear