FASTENER GP 4646565 - Caterpillar

The Machine Creeps
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Check for the symptom.
Determine that the symptom is active.
Complete this procedure only if the symptom is active.
Conduct recalibration of the pump and motors.Guidelines to check the calibrations of the pump and motor refer to Specifications, System Operations, Testing and Adjusting, KENR5148, "Calibration", "Transmission Drive Pump Pressure Override Calibration"Results
OKAY: Proceed to Step 5.
Conduct the mechanical adjustment procedure for the neutral position of the piston pump.Guidelines to check the adjustment of the piston pumps refer to Specifications, System Operations, Testing and Adjusting, KENR5148, "Piston Pump Nuetral - Adjustment", "Mechanical Adjustment"Results
OKAY: Proceed to Step 6.
Conduct the hydraulic adjustment procedure for the neutral position of the piston pump.Guidelines to check the adjustment of the piston pumps refer to Specifications, System Operations, Testing and Adjusting, KENR5148-00, "Piston Pump Nuetral - Adjustment", "Hydraulic Adjustment"Results
OKAY: Proceed to Step 7.
Conduct recalibration of the machine through ET.Guidelines to check the calibrations of the pump and motor refer to Specifications, System Operations, Testing and Adjusting, KENR5148, "Calibration", "Hystat Pump and Motor Solenoid Calibration"Jerky Modulation
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Check for the symptom.
Determine that the symptom is active.
Complete this procedure only if the symptom is active.
Conduct recalibration of the pumps and motors.Guidelines to check the calibrations of the pump and motor refer to Specifications, System Operations, Testing and Adjusting, KENR5148, "Calibration", "Transmission Drive Pump Pressure Override Calibration"Results
OKAY: Proceed to Step 5.
Determine if the tractor has jerky modulation above speed ratio 1.5.Guidelines to review values in ET refer to Specifications, System Operations, Testing and Adjusting, KENR5148, "Calibration", "Transmission Drive Pump Pressure Override Calibration"Results
If the machine has jerky modulation at a speed ratio of 0 - 1.5, proceed to Step 6.
If the machine has jerky modulation at a speed ratio of 1.5 - 3.0, proceed to Step 10.
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General location of the pump's "X1" and "X2" ports
View pressure increases on the charge oil for the Forward/Reverse solenoids of the hydrostatic pumps.Make sure that the spool is not sticky. Place the machine on stands. Attach pressure gauges to "X1" and "X2" ports of the hydrostatic pumps. While the tracks are slowly moving, slowly increase the speed range. The pressure at gauges "X1" and "X2" should slowly increase. This should be a smooth transition.Results
OKAY: proceed to Step 11.
NOT OKAY: Proceed to Step 7.
Inspect the pump's electronic pressure control spool.Results
OKAY: proceed to Step 8.
NOT OKAY: Repair the problem and proceed back to Step 6.
Inspect the pump's actuator piston and the bore for roughness.Results
OKAY: proceed to Step 9.
NOT OKAY: repair the problem and proceed back to Step 6.
Conduct recalibration of the pumps and motors.Guidelines to check the calibrations of the pump and motor refer to Specifications, System Operations, Testing and Adjusting, KENR5148, "Calibration", "Transmission Drive Pump Pressure Override Calibration"Results
NOT OKAY: proceed to Step 11.
Test the initiation of the motors.Start the machine and operate the engine at HIGH IDLE. Move the transmission and steering control to the FORWARD position. The travel motors will initiate at a ground speed of approximately 4 km/h (2.5 mph).ResultsTHE MACHINE MOMENTARILY JOGS TO EITHER SIDE: perform Step 11 on only one of