TUBE AS 3642875 - Caterpillar

Cycle Time Checks
Hydraulic oil pressure can remain in the hydraulic system on this machine after the engine and pump have been stopped. Serious injury can result if this pressure is not released before any service is done on the hydraulic systems. In order to prevent possible injury, release the hydraulic system pressure before working on any fitting, hose, or hydraulic component.Lower all attachments to the ground before service is started. If the hydraulic system must be serviced, tested, or adjusted with the attachment in the raised position, the attachments and lift cylinders must be supported properly.Always move the machine to a location away from the travel of other machines. Be sure that other personnel are not near the machine when the engine is running and tests or adjustments are being made.
All of the cycle time checks are performed with the engine at high idle.The oil in the hydraulic system must be at an operating temperature of approximately 75° 5°C (167° 9°F).If the test results are in agreement with the table, the circuit is normal.The relief valve must be tested in order to be sure that the opening pressure of each valve is correct. Refer to Systems Operation, "Relief Valve Pressure (Fan Drive) - Test and Adjust". See the table 1 for the relief pressure setting.Follow Step 1 through Step 3 first in order to perform the cycle times:
Check the system oil level.
Check for leaks in the inlet to the implement pump.
Review hydraulic oil samples.
Table 1
Cycle Time
Bulldozer Lift Cylinder Time in Seconds Temperature of Oil
Move the blade from the ground to the fully raised position. 6.5 71°C (160°F)
Table 2
Cycle Time
Bulldozer Tilt Cylinder (Single Tilt) Time in Seconds Temperature of Oil
Move the bulldozer blade from tilt right to tilt left. 5.1 71°C (160°F)
Move the bulldozer blade from tilt left to tilt right. 4.2 71°C (160°F)
Table 3
Cycle Time
Bulldozer Tilt Cylinder (Dual Tilt) Time in Seconds Temperature of Oil
Move the bulldozer blade from tilt right to tilt left. 5.1 71°C (160°F)
Move the bulldozer blade from tilt left to tilt right. 5.1 71°C (160°F)
Table 4
Cycle Time
Ripper Cylinders Time in Seconds Temperature of Oil
Move the ripper to the fully raised position from the fully lowered position. 5.9 71°C (160°F)
Move the ripper to the fully lowered position from the fully raised position. 6.9 71°C (160°F) If the travel time is not correct, review the following diagnostics:
If all the circuits are slow, check or perform the following procedure: Follow Step 1 through Step 8.
Blade lift (only) is too slow: Follow Step 9 and Step 10.
Blade tilt (only) is too slow: Follow Step 11 and Step 12.
Ripper lift (only) is too slow: Follow Step 13 through Step 15.
The ripper tip (only) is too slow: Follow Step 16 through Step 18.
Perform the pilot oil pressure and check the pilot oil supply.
Perform the procedure for implement calibration. Refer to Calibration, RENR7545.
Check the pressure reducing valve for