COUPLING-TORSIONAL 4431551 - Caterpillar

Table 1
Required Tools    
Part Number     Description     Qty    
8T-5320     Hydraulic Test Group     1    
1U-5481     Pressure Gauge Group     1    
4G-4890     Pressure Gauge Kit     1    
1U-5482     Pressure Adapter Group     1    
Personal injury can result from hydraulic oil pressure and hot oil.Hydraulic oil pressure can remain in the hydraulic system after the engine has been stopped. Serious injury can be caused if this pressure is not released before any service is done on the hydraulic system.Make sure all of the attachments have been lowered, oil is cool before removing any components or lines. Remove the oil filler cap only when the engine is stopped, and the filler cap is cool enough to touch with your bare hand.
Care must be taken to ensure that fluids are contained during performance of inspection, maintenance, testing, adjusting and repair of the product. Be prepared to collect the fluid with suitable containers before opening any compartment or disassembling any component containing fluids.Refer to Special Publication, NENG2500, "Caterpillar Tools and Shop Products Guide" for tools and supplies suitable to collect and contain fluids on Caterpillar products.Dispose of all fluids according to local regulations and mandates.
Read Testing and Adjusting, "Machine Preparation for Troubleshooting" and understand Testing and Adjusting, "Machine Preparation for Troubleshooting" in this manual before performing the following procedure.Pilot oil for the steering system is supplied from a pressure reducing valve. The location of the pressure reducing valve is located in the pilot control valve. The pilot control valve is located in the non-engine end frame of the machine.
Illustration 1 g00731040
Use the following procedure to test the supply oil pressure for the pilot system while the engine is running:
Shut off the engine.
Attach the hose and the pressure gauge to test port (1) .
Start the engine and allow the engine to run at high idle. At normal temperature, the pressure reading should be 3450 100 kPa (500 14.5 psi).
Illustration 2 g00731184
If the pressure reading is not correct, the pressure reducing valve needs to be adjusted. The pressure reducing valve (1) is located on the right side of the pilot control valve. Loosen the locknut (2) on the pressure reducing valve. Turn the adjusting screw (3) clockwise in order to increase the pressure. Turn the adjusting screw (3) counterclockwise in order to decrease the pressure.
Perform steps 3 through 4 until the correct pressure is reached.Selector and Pressure Control Valve
A selector and pressure control valve has been added in order to enhance the start of steering modulation during some applications.
Illustration 3 g00731251
The selector and pressure control valve (1) is located between the pilot control valve and the steering pilot valve. The selector and pressure control valve is located below the steering pilot valve. A pressure tap (2) is provided in order to test the pressure of the pilot oil after the oil exits the selector and pressure control valve.The selector and pressure control valve lowers the pressure of pilot oil