PINION-SHAFT 5048842 - Caterpillar

Illustration 28 g00704657
(1) Reflective tape
One wheel on each side of the machine must be checked for proper speed. Apply four pieces of reflective tape (1) to each wheel at 90 degree intervals. Use a 1U-6602 Phototach to record the RPM of the wheels.
Start the machine and run the machine at high idle. Push in the FORWARD direction on the joystick control (hydrostatic). Record the RPM of a wheel on each side of the machine and divide that number by four.
Record the MA pressures, the speed sensing pressures, the charge pressure and the wheel RPM.
Table 5
Test F For The 228 Skid Steer Loader And 248 Skid Steer Loader
The Maximum Speed Test For The Displacement Control For The Pumps And For The Motors In The Forward Direction    
Test     Spec     Actual    
Speed Sensing Pressure for the 228 Skid Steer Loader    
2200 100 kPa (319.0 15.0 psi)        
Speed Sensing Pressure for the 248 Skid Steer Loader    
2500 100 kPa (363.0 15.0 psi)        
Charge Pressure    
3200 200 kPa (464.0 29.0 psi)        
MAPressure    
6000 500 kPa (800 85 psi)        
Wheel RPM     80 8 rpm
The wheel speeds must be within 2 RPM of each other.        Perform the following check if the pump signal pressure is not to the correct specification.
The speed sensing valve may be misadjusted.Perform the following check if the MApressure and the MB pressure is high for the FORWARD and the REVERSE directions.
The axle may have a problem.
The brake may not be released.
The chain drive may be out of adjustment.Test F
Brake Test
This test will determine if the brakes are functioning correctly. This test will check the interlock manifold and the piston motor (hydrostatic).
Raise the cab. Refer to Operation and Maintenance Manual, SEBU7255, "Cab Support Operation" for the 248 Skid Steer Loader. Refer to Operation and Maintenance Manual, SEBU7205, "Cab Support Operation" for the 228 Skid Steer Loader.
Illustration 29 g00699520
Disconnect the brake solenoid electrical connection (1) .
Install one 3J-1907 O-Ring Seal on a 6V-3965 Fitting. Install the fitting on a 8T-8902 Tee .
Illustration 30 g00699624
Install the 8T-8902 Tee (2) in the hydraulic line that runs from the interlocking manifold valve and mounting to the piston motors (hydrostatic). To install the tee, move the hose to the piston pump (hydrostatic).
Install a 8T-0855 Pressure Gauge to the end of a 177-7860 Hose .
Install the other end of the 177-7860 Hose to the diagnostic tee.
Lower the cab.
Start the machine. The pressure gauge should read 0. If the gauge does not read 0, inspect the