ANGLE 1688040 - Caterpillar

Checking Steering Effort
The force required to turn the steering wheel should not exceed 4 lb. (1,8 kg) when measured with a spring scale at the steering wheel rim.Checking Steering Speed
The minimum steering time should be approximately equal for a left to right turn and right to left turn. With the engine at high idle RPM, the time for these turns is 9 to 11 seconds.If the steering speeds are within tolerances, the pump is probably within specifications. PROBLEM: Steering wheel turns hard in both directions. PROBABLE CAUSE:1 Binding between nut gear and sector gear in the steering gear.2 Steering control valve linkage binding or damaged.3 Follow-up linkage damaged.4 Drain line damaged or plugged, restricting valve spool movement.5 Binding between steering column and steering shaft. PROBLEM: Machine steers slow in both directions. PROBABLE CAUSE:1 Low pump output.2 Inadequate control valve spool movement.3 Relief valve setting low.4 Relief valve leaking. PROBLEM: Machine steers slow in one direction only. PROBABLE CAUSE:1 Inadequate control valve spool movement in one direction (valve spool not centered).2 Steering control linkage incorrectly adjusted.3 Follow-up linkage damaged. PROBLEM: Jerky or erratic steering. PROBABLE CAUSE:1 Air in system.2 Malfunction of follow-up linkage.3 Excessive backlash between the nut gear and sector gear in the steering gear.Instrumentation Tests
5S5123 Hydraulic Testing Group, 5S8875 Hydraulic Test Box Group.Tests must be made with the oil at normal operating temperature. Loosen the filler cap on hydraulic tank to relieve tank pressure before installing or removing test equipment.Testing and Adjusting Steering Relief Valve Setting
Install a 0-4000 PSI pressure gauge in tap (2).
TESTING STEERING VALVE RELIEF PRESSURE
1-Cover. 2-Pressure tap (relief valve).With the engine at high idle speed, turn the machine into the stop and check the pressure at pressure tap (2). The pressure relief setting should be 1500 25 PSI (105,5 1,8 kg/cm2).Add or remove shims under cap (1) to adjust the relief valve pressure. One shim changes the relief setting approximately 40 PSI (2,8 kg/cm2).Testing and Adjusting Steering Unloading Valve Pressure
Install a 0-4000 PSI pressure gauge at tap (3).
TESTING STEERING VALVE UNLOADING PRESSURE
3-Pressure tap (unloading).Start the engine, fully depress the governor pedal, turn the machine into the stop block. Unloading pressure should be 1400 25 PSI (98,4 1,8 kg/cm2).Add or remove shims under cover (4) to adjust the unloading pressure. Each shim affects the pressure 50 PSI (3,5 kg/cm2).
STEERING VALVE
4-Cover.Testing and Adjusting Steering Cylinder Pressure Balance
Connect a 0-1000 PSI pressure gauge to the head end inlets of both steering cylinders by using pressure plate connectors. Use of the same gauge with shutoff valves for reading both cylinders eliminates inaccurate balance readings.With the steering wheel motionless and the engine running at HIGH IDLE, the pressure at the two connections should be 195 45 PSI (13,7 3,2 kg/cm2) and one reading should be within 40 PSI (2,8 kg/cm2) of the other.
Center the steering wheel. Do not move the steering wheel during this test. High pressures will result, causing damage to the gauge.
If pressures are not equal within 40 PSI (2,8 kg/cm2),