INSULATION 1188437 - Caterpillar

host machine must be operated at high idle during this check.
Move the host machine with the work tool to a smooth level location.
Turn off the engine of the host machine and activate the parking brake.
Conduct a good visual inspection of all hoses, fittings, and components. If any leaks or damage is observed, replace the faulty components before you attempt this check.
Start the host machine and run the machine at high idle. Operate the implements until the hydraulic oil reaches normal operating temperature.
Fully open the shells of the work tool.
Close the shells of the work tool and record the cycle time.
Open the shells of the work tool and record the cycle time. The proper cycle times are listed below.Four shellOpen ... 1.4 secondsClose ... 2.3 secondsFive shellOpen ... 1.8 secondsClose ... 2.9 seconds
If the cycle times are correct, the shell circuit is operating properly. If the cycle times are not correct, check the oil flow and the oil pressure from the host machine. Refer to the Service Manual, "Host Machine Pressure and Flow - Test". The oil flow to the cylinders must be 200 L/min (52.8 US gpm). The oil pressure to the cylinders must be 32500 2500 kPa (4720 360 psi).
If an adjustment was made to the host machine, repeat the check. If the cycle times do not meet the specifications, perform a cylinder leakage test. Refer to Service Manual, "Hydraulic Cylinder Leakage - Test".