ELBOW 9L6760 - Caterpillar

Specifications
Table 1
993K Steering Cycle Times
Description Specification Actual
Steering Cycle Time 4.4 0.3 Seconds Introduction
The following procedure should be used in order to help determine if there is a problem with the steering pump. Pump performance should be checked if the machine has slow steering times.This information includes the following test:
Pump Performance (Steering) - TestRequired Tools
Table 2
Qty Part No Description
1 Stop Watch Pump Performance (Steering) - Test
Machine Preparation
Move the machine to a smooth level surface. Move away from working machines and personnel. Lower the work tool to the ground.
Allow only one operator on the machine. Keep all personnel away from the machine or in the view of the operator.
Engage the parking brake. Steering Cycle Time
The steering time is affected by the amount of oil flow that is produced by the steering pump. Check the steering times in order to determine if there is a problem with the steering pump.
Perform the machine preparation for testing.
Start the engine. Operate the engine at high idle. Continuously stall the RACK BACK function while simultaneously raising the lift arms at full speed. When the lift arms are almost raised, cycle the tilt cylinder almost to the FULL DUMP position. Then move the tilt cylinders to the full RACK BACK position. Continuously stall the RACK BACK function and simultaneously lower the lift arms back to the ground level position. Without stalling the RACK BACK function, cycle the lift function to raise the lift arms fully. Then lower the lift arms in order to allow the pump to operate at low-pressure briefly and circulate oil through the system. Repeat this process in order to increase the temperature of the oil to normal operating temperature.
Raise the work tool slightly off the ground.
Maintain the engine speed at rated engine speed.
Record the steering time from stop to stop. The steering time for the 993K Wheel Loader should be 4.4 0.3 seconds.
Lower the boom and place the work tool flat on the ground.
Reduce engine speed to low idle.
Stop the engine. Compare the test results with the cycle times that are listed. The steering pump should be working properly if the cycle times match the cycle times that are listed.If the cycle times are not correct, one of the following conditions may be present:
The pressure setting for the backup relief valve is not within specifications.
The pump is not upstroking.
The pump may have excessive wear.The main relief pressure should be measured. If the main relief pressure is low, the cycle times should be retested after the main relief pressure has been corrected.Reference: For more information on Testing and Adjusting the main relief valve, refer to the Service Manual module Testing and Adjusting, "Relief Valve (Pump Backup)