HYDRAULIC AR 1096663 - Caterpillar

Introduction
This test will determine why the machine does not swing and the engine has a load when operating the swing pilot control lever. 1. Check swing parking brake release pressure.a. Place machine on level ground and stop the engine.b. Release the pressure in the hydraulic system. Refer to, "Release Of Pressure In the Hydraulic System" Form SENR6187.
Swing Motor
(1) Port (swing parking brake pilot supply).c. Install a 4000 kPa (580 psi) gauge at pilot supply pressure port (1) in the swing parking brake valve.d. Move the swing pilot control lever to swing LEFT or RIGHT position and check the pressure to the swing parking brake. Expected Result:Pressure to the swing parking brake should be approximately 3450 kPa (500 psi). Results:* OK - Proceed to Step 2.* NOT OK - Replace the swing parking brake valve. STOP.2. Check condition of swing drive and/or swing gear and bearing.Inspect the swing internal gear. Remove the cover at the base of the boom mount and/or the cover inside the car body and inspect the swing internal gear. If upper structure cannot swing, the above inspection will be for a very small part of the gear.Inspect the swing drive.a. Remove the swing motor and inspect the upper swing drive through the mounting hole for the motor.b. If no failure is evident, remove the swing drive and inspect it.c. While swing drive is removed, inspect the internal gear.Reference: Refer to SENR6189 for additional information. Results:* OK - Proceed to Step 3.* NOT OK - Repair damaged swing drive or swing gear and bearing. STOP.3. Perform Swing Motor Case Drain Test. For further information refer to the section, "Swing Motor Case Drain Test". Results:* OK - STOP.* REPAIRED, OK - STOP.