CLAMP-V BAND 4346544 - Caterpillar

Personal injury or death can result from sudden machine movement.Sudden movement of the machine can cause injury to persons on or near the machine.Prevent possible injury by performing the procedure that follows before working on the machine.Move the machine to a smooth horizontal location. Move away from working machines and personnel and lower the buckets or implements (loader and backhoe) and stabilizers to the ground.Permit only one operator on the machine. Keep all other personnel away from machine or in view of the operator.Engage the parking brake. Stop the engine.Move the hydraulic control levers to all positions to release the pressure in the hydraulic system.
This test is used to determine the location of a problem in the steering hydraulic system.
Table 1
Required Tools    
Item    Qty    Description    
A     2     8T-0861 Pressure Gauges (0 to 60,000 kPa (0 to 8700 psi))    
2 171-1879 Adapter    
2 187-3547 Fitting    
2 177-7863 Hose As    
4 187-3546 Coupler    
B     2     8T-0855 Pressure Gauges (
0 to 4000 kPa (0 to 580 psi))    
2 177-7861 Hose As    
4 6V-4143 Coupler    
Move the machine to an open area that is flat. Lower all the implements to the ground and stop the engine.
Illustration 1 g01361161
Illustration 2 g01830498
Install tooling (A) on pressure taps (HC) and (HD) . Install tooling (B) on pressure taps (Y1) and (Y2) .Note: Taps (HC) and (HD) require quick couplers and hoses that are rated for high pressure. Standard quick couplers and hoses will not work.Note: If only two hoses and gauges are available, install the hoses first on pressure taps (HC) and (Y1) . Then, install the hoses on pressure taps (HD) and (Y2) .
Start the engine and run the engine at HIGH IDLE.
Engage the parking brake and place all controls in the HOLD position. Record the pressures on the four gauges. The readings on gauges (Y1) and (Y2) should be below 200 kPa (30 psi). If either of the pressures is higher, the steering pump could be trying to steer in one direction. This could be caused by one of the following reasons.
The pilot valve is improperly adjusted or aligned.
The steering pump controls are faulty.
The pilot control valve is faulty.
The reading on pressure gauges at pressure taps (HC) and (HD) should be 2500 300 kPa (365 45 psi).If either pressure is higher, then the charge pressure relief valve is improperly adjusted or faulty or the oil temperature is too low. If the pressures are too low, then there is a problem in the charge circuit. This could be caused by one of the following reasons.
The charge pressure relief valve is improperly adjusted or failed.
There is a leak in the charge circuit.
The motor or the motor flushing valve has wear.
The cold start valve is worn or improperly adjusted.
The oil level is low.
The charge pump is worn.
The steering pump is worn.
Make sure that the transmission is in NEUTRAL. Disengage the parking