WRENCH-BOX 6V4165 - Caterpillar

Table 2
Charging Pressure and Temperature Relationship for the 9J-9865 Accumulator (
2068 kPa (300 psi))    
Temperature    Pressure (1)    
-7°C (20°F)    
1862 kPa (270 psi)    
-1°C (30°F)    
1903 kPa (276 psi)    
4°C (40°F)    
1944 kPa (282 psi)    
10°C (50°F)    
1986 kPa (288 psi)    
16°C (60°F)    
2027 kPa (294 psi)    
21°C (70°F)    
2068 kPa (300 psi)    
27°C (80°F)    
2110 kPa (306 psi)    
32°C (90°F)    
2151 kPa (312 psi)    
38°C (100°F)    
2192 kPa (318 psi)    
43°C (110°F)    
2234 kPa (324 psi)    
49°C (120°F)    
2275 kPa (330 psi)    
( 1 ) The allowable tolerance on the nominal pressure is 35 kPa (5 psi).Check that the engine has not been running for at least five minutes. This will allow the oil level in the steering accumulator to decrease. The accumulator bladder must be on the bottom of the cylinder. This will ensure that the pressure of the nitrogen charge is correct.The accumulator has a dry charge of approximately 2068 kPa (300 psi).Checking the Nitrogen Charge
Illustration 1 g00281220
Nitrogen charging group (1) Pressure gauge (2) Connection to nitrogen cylinder valve (3) Regulator assembly (4) Valve (5) Pressure gauge (6) Pressure regulating screw (7) Valve handle (8) Chuck
Illustration 2 g00727361
(9) Cap
Remove cap (9) from the top of the accumulator. Install Tool (B) on the accumulator valve.
Install chuck (8) on Tool (B) .Note: Do not connect the hose to valve (4). Make sure that valve (4) is closed.
Turn valve (7) on chuck (8) clockwise.
Use 13800 kPa (2000 psi) pressure gauge (5) to check the nitrogen charge in the accumulator.
The pressure on the gauge must be within the tolerances that are listed in Table 2.
If the pressure reading on the gauge is too high, lower the pressure by slowly opening valve (4) .
If the pressure reading on the gauge is too low, charge the accumulator.Charging the Accumulator
Close valve (4) .
Connect the hose from valve (4) to pressure gauge (1). The hose is part of the nitrogen charging group.
Open the valve on the nitrogen cylinder. Adjust screw (6) on the regulator assembly until gauge (1) is at the pressure that will charge the accumulator. Use Table 2 as a reference for the correct charging pressure.
Open valve (4) and charge the accumulator.
When the pressure reading on gauge (5) and the pressure reading on gauge (1) are identical, shut valve (4) .
If there is a decrease in pressure on gauge (5), open valve (4). This allows more nitrogen to enter the accumulator.
Repeat Steps 5 and 6 until the following items occur:
Pressure readings of gauges (5) and (1) are identical.
Pressure readings do not change.
Close the valve on the nitrogen cylinder.
Turn valve (7) on chuck (8) counterclockwise.
Remove the test equipment.Charging a Rebuilt Accumulator
Remove all nitrogen from the end of the accumulator. When the accumulator is rebuilt, put approximately 0.9 L (1 qt) of SAE 10W hydraulic oil in the end of the accumulator that holds nitrogen. This oil will be