CONTROL GP-CAB TILT 2371174 - Caterpillar

Introduction
The control valves spools must shift at the proper pilot supply pressure. Proper shifting prevents interaction between the main control valves, the stick II and boom II valves, insures controllability, and makes certain the main control valve spool is shifting completely.This test provides a means for checking the main control valve for the correct shift actuation pressures. Check control valve shifting pressure
a. Place the 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.
Main Control Valve
(1) Stick II control valve. (2) Bucket control valve. (3) Boom I control valve. (4) Attachment control valve. (5) Right travel control valve. (6) Left travel control valve. (7) Swing control valve. (8) Stick I control valve. (9) Boom II control valve.c. Install a swivel tee fitting into the pilot signal line of the circuit being tested.d. Connect a 4000 kPa (580 psi) gauge to the tee.
Pump Compartment
(10) Tap (rear pump). (11) Tap (front pump).e. Install 60 000 kPa (8700 psi) gauges at tap (10) and tap (11) on the front and rear pumps.
Main Control Valve
(12) Elbow. (13) Line (swing brake pilot signal).f. If testing the travel circuit, block the tracks to prevent movement. If testing swing, prevent the swing parking brake from releasing by disconnecting the pilot signal line (13) from elbow (12) and plug. Leave line (13) open to the air.g. Increase the hydraulic system temperature to the normal operating temperature.h. Slowly move the pilot control of the circuit being tested and observe when the pump supplying the flow to the circuit begins to show an increase in pressure or when the implement begins to move.i. When the pump pressure begins to increase or the implement begins to move, check the pilot signal pressure to the main control valve.j. If checking boom RAISE pilot supply pressure, continue to move the pilot control lever while watching for the pressure to increase at the rear pump tap (10). The instant there is an increase in pressure at the rear pump, check the pilot signal pressure to the main control valve.k. If checking stick OUT pilot supply pressure, continue to move the pilot control lever while watching for the pressure to increase at the front pump tap (11). The instant there is an increase in pressure at the front pump, check the pilot signal pressure to the main control valve.l. Continue to move the pilot control lever until the implement has reached maximum travel position (tracks blocked to prevent movement or swing brake release signal disconnected).m. Return the pilot control lever to its NEUTRAL position.n. Slowly move the pilot control lever of the circuit being tested in the direction of the bottomed implement.o. The instant the pump reaches main system relief pressure [23 000 kPa (3350 psi) swing, 31 400 kPa (4550 psi) implement, or 34 300 kPa (5000 psi) travel], check the pilot signal pressure of the circuit being tested. Expected Result:* At approximately 700 kPa (100