CAMSHAFT-FUEL PUMP 1312746 - Caterpillar

Discharging the Accumulator
Ensure that the oil in the hydraulic system is at normal operating temperature. Park the machine on a smooth, level surface.
Install the steering frame lock. Block the wheels. Stop the engine.
Turn the engine start switch to the ON position. Move the joystick and the control levers through the full range of travel.Note: Moving the joystick and moving the levers will release the pressure in the pilot hydraulic system.
Illustration 3 g01043975
Raise the door on the rear of the machine in order to access the pilot accumulator.
Illustration 4 g01043976
Accumulator for the pilot valve
Illustration 5 g01043978
Remove guard (1) which protects nitrogen charging valve (2) .
Remove the protective cap on nitrogen charging valve (2) .
Illustration 6 g00282185
(3) Nipple. (4) Coupling assembly. (5) Pressure gauge. (6) Hose assembly. (7) Coupling assembly. (8) Nipple. (9) Valve. (10) Pressure gauge. (11) Regulator assembly. (12) Pressure regulating screw. (13) Chuck for the nitrogen cylinder valve. (14) Valve handle. (15) Nitrogen charging chuck. (16) Hose assembly. (17) Tee.
Identify the correct nitrogen charging chuck.Note: For a nitrogen charging valve with a .305 inch -32 THD, use a 1S-8938 Nitrogen Charging Chuck and a 1U-5551 Extension Assembly. For a nitrogen charging valve with a .482 inch -26 THD, use a 7S-5106 Nitrogen Charging Chuck and a 7S-5439 Extension Assembly .
Attach hose assembly (16) to nitrogen charging chuck (15) .
Turn the valve handle (14) on nitrogen charging chuck (15) all the way in the counterclockwise direction. This will ensure that nitrogen charging valve (2) will not be opened when nitrogen charging chuck (15) is attached to the nitrogen charging valve.
Attach nitrogen charging chuck (15) and hose assembly (16) to nitrogen charging valve (2) .
Attach nitrogen charging chuck (15) and hose assembly (16) to nitrogen charging valve (2) .
Place the open end of hose assembly (16) away from the work area and away from other personnel.
Turn valve handle (14) on nitrogen charging chuck (15) all the way in the clockwise direction in order to open nitrogen charging valve (2). This will release all of the compressed gas from the accumulator through hose assembly (16). Now, the accumulator can be removed from the machine.
Disconnect the hydraulic lines for servicing, as needed.Nitrogen Charging Procedure
Table 2
Required Tools    
Part Number     Description     Quantity    
175-5507     Nitrogen Charging Group     1    
8T-0854     Pressure Gauge     1    
Illustration 7 g00107133
Nitrogen Charging Group (1) Nipple. (2) Coupling assembly. (3) Pressure gauge. (4) Hose assembly. (5) Coupling assembly. (6) Nipple. (7) Valve. (8) Pressure gauge. (9) Regulator assembly. (10) Pressure regulating screw. (11) Chuck for the nitrogen cylinder valve. (12) Valve handle. (13) Chuck. (14) Hose assembly.
Ensure that valve (7) is closed. Install chuck (13) onto the pilot accumulator. Turn valve handle (12) completely in the clockwise direction.
If the reading on pressure gauge (8) is too high, slowly open valve (7) in order to lower the pressure. If the reading on the pressure gauge is too low, use the following procedure to charge the accumulator:
Connect a hose from the nitrogen cylinder to chuck (11)