SEAL AS 1439740 - Caterpillar

Table 3
Accumulator Precharge Pressure/Temperature Relationship for a Typical Accumulator with a Precharge of
2070 kPa (300 psi)    
Temperature     Pressure (1)    
−7°C (20°F)    
1790 kPa (260 psi)    
−1°C (30°F)    
1835 kPa (266 psi)    
4°C (40°F)    
1875 kPa (272 psi)    
10°C (50°F)    
1915 kPa (278 psi)    
16°C (60°F)    
1955 kPa (284 psi)    
21°C (70°F)    
2070 kPa (300 psi)    
27°C (80°F)    
2110 kPa (306 psi)    
32°C (90°F)    
2150 kPa (312 psi)    
38°C (100°F)    
2200 kPa (319 psi)    
43°C (110°F)    
2250 kPa (326 psi)    
49°C (120°F)    
2300 kPa (334 psi)    
( 1 ) Nominal allowable tolerance equals 35 kPa ( 5 psi).
Open needle valve (9). The nitrogen pressure should show on the 8T-0858 Pressure Gauge within 20 seconds.Note: If the nitrogen pressure shows on the pressure gauge in less than 10 seconds, close screw (12) on regulator assembly (11) and disconnect hose assembly (6) at coupling assembly (4). Close needle valve (9) and remove coupling assembly (4). Repeat Steps 7 through 20.
If the ride control accumulator is properly charged, then turn tee handle (14) on nitrogen charging chuck (15) all the way in the counterclockwise direction. Close needle valve (9).
Release the ride control switch. The ride control switch will return to the OFF position.
Turn the valve on the nitrogen cylinder clockwise in order to shut off the flow of nitrogen. Turn screw (12) on regulator assembly (11) counterclockwise, until the pressure on gauge (5) goes back to zero.
Slowly disconnect hose (16) from needle valve (9) .
Open needle valve (9) before you remove nitrogen charging chuck (15) from nitrogen charging valve (2) on the accumulator.
Remove nitrogen charging chuck (15) from the ride control accumulator.
Install the cap on the nitrogen charging valve. Install guard (1) over nitrogen charging valve (2) .Charging Procedure for a New or Rebuilt Accumulator
Prior to installing the ride control accumulator, it is necessary to remove all the air from the nitrogen chamber of the accumulator. When the accumulator is new or rebuilt, put approximately 1.9 L (2.01 qt) of SAE 10W hydraulic oil in the nitrogen end of the accumulator. This oil will be used to help remove the air out of the nitrogen chamber of the ride control accumulator and also to put lubricant at the top seal of the accumulator piston.
Discharge the ride control accumulator. Refer to "Discharging the Accumulator".
Illustration 7 g01036089
Ride control accumulator (1) Guard (2) Nitrogen charging valve
Remove guard (1) which protects nitrogen charging valve (2) .
Remove nitrogen charging valve (2) .
With the accumulator in the vertical position put approximately 1.9 L (2.01 qt) of SAE 10W hydraulic oil in the nitrogen end of the accumulator.
Move the accumulator piston fully to the nitrogen charging valve end of the accumulator. As the accumulator piston moves to the nitrogen charging valve end of the accumulator, the air and then the oil will be pushed out. When the flow of oil stops the accumulator