PUMP GP-PISTON 2613629 - Caterpillar

Testing Pressure Relief Valve
1. Remove the floor plate directly in front of the operator's seat.
CROSS SECTION OF STEERING CONTROL VALVE
1. Plug. 2. Shims (main relief valve). 3. Shims (balance cylinder pressure). 4. Plug (main relief pressure tap location).2. Remove the test plug (4) and install necessary fittings, hose and a 0 to 4000 psi pressure gauge.
STEERING CONTROL VALVE
4. Plug.3. Install a FT508 Stop Block on a frame stop.4. With engine at high idle speed, turn the machine against the stop block and hold the steering wheel turned. The pressure relief valve setting should be in the range of 2000 25 psi (140.6 1.8 kg/cm2).5. Add or remove shims (2) to adjust the relief valve setting. Adding shims increases the pressure setting. Tighten plug (1) to 36 4 lb. ft. (5.0 0.6 mkg). Tighten plug (4) to 24 2 lb. ft. (3.3 0.3 mkg). Testing Cylinder Pressure Balance6. Install the appropriate plate assemblies between lines (12 and 13) and steering control valve. Install a hose assembly and 0 to 200 psi gauge in each plate assembly.
Connect the steering safety link.
STEERING CONTROL VALVE AND RELATED LINKAGE
5. Nut and lock. 6. Eyebolt assembly. 7. Nut. 8. Housing assembly. 9. Setscrew. 10. Locknut. 11. Lever. 12. Oil line. 13. Oil line. 14. End. 15. Nut. A. .50 in. (12.7 mm) reference dimension. B. Total linear movement when steering wheel is rotated from lock to lock [approximately 1.15 in. (29.2 mm)]. (Floor plates removed for illustration purposes.)7. Disconnect end (14) from valve spool. Disconnect eyebolt assembly (6) from follow-up mechanism.8. The steering valve spool is centered by a centering spring. With the diesel engine operating at high idle speed, the pressure on each gauge (at lines 5 and 6) will be in the approximate range of 85 15 psi (6.0 1.0 kg/cm2). The difference between the pressures must not vary more than 20 psi (1.4 kg/cm2). If the gauge reading connected to line (13) is higher, add shims (3).
When making tests with low pressure gauges installed, make certain the steering wheel is not turned. The high oil pressure which turns the machine will damage the gauges.
Steering Gear AdjustmentIf troubleshooting the system or when assembling the steering gear, the following items should be checked.9. At assembly make certain the center tooth of the sector gear meshes with center notch of the nut gear (with right hand side cover removed).10. Backlash between the sector gear and nut gear is set at .000 to .006 in. (0.0 to 0.15 mm). Rotate the eccentric sector gear shaft housing (8) for adjustment (with right hand side cover removed).11. Tighten setscrew (9) to remove end clearance of shaft, back out screw (9) 1/8 turn, and tighten locknut (10) to 50 5 lb. ft. (6.9 0.7 mkg).12. The steering control valve spool should be in the NEUTRAL or centered position because of a centering spring. Turn the steering wheel to its extreme left and right positions while noting the linear