GASKET-OIL CLR 3990459 - Caterpillar

Dry nitrogen is the only gas approved for use in the accumulators. The charging of oxygen gas in an accumulator will cause an explosion. An explosion can be eliminated by using nitrogen gas cylinders with standard CGA (Compressed Gas Association, Inc.) No. 580 connectors. When nitrogen gas is ordered, make sure to order the cylinders with CGA No. 580 connectors.Do not rely on color codes or other methods of identification to tell the difference between nitrogen and oxygen cylinders. In any application, never use an adapter to connect your nitrogen charging group to a valve outlet used on both nitrogen, oxygen, or other gas cylinders. BE SURE YOU USE DRY NITROGEN (99.8% purity).
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, "Dealer Service Tool Catalog" for tools and supplies suitable to collect and contain fluids on Cat® products.Dispose of all fluids according to local regulations and mandates.
Table 2
Accumulator Precharge Pressure/Temperature Relationship for the 690 kPa (100 psi) Service Brake Accumulators
Temperature Pressure
−7°C (20°F) 625 kPa (91 psi)
−1°C (30°F) 638 kPa (92 psi)
4°C (40°F) 651 kPa (94 psi)
10°C (50°F) 664 kPa (96 psi)
16°C (60°F) 677 kPa (98 psi)
21°C (70°F) 690 kPa (100 psi)
27°C (80°F) 703 kPa (102 psi)
32°C (90°F) 716 kPa (104 psi)
38°C (100°F) 729 kPa (106 psi)
43°C (110°F) 742 kPa (108 psi)
49°C (120°F) 755 kPa (110 psi) Preparation for Testing
Ensure that the oil in the hydraulic system is at normal operating temperature. Park the machine on a smooth, level surface.
Fully lower the machine. Lower the work tool to the ground. Place the operating mode switch in the NEUTRAL position.
Install the steering frame lock. Block the wheels. Install the swing lock pins. Stop the engine.
Turn the engine start switch to the ON position. Ensure that the boom switch is in the ON position. Move the implement joysticks, the steering joystick, and the pendulum arm joystick through the full range of travel.Note: Moving the joysticks will release the pressure in the pilot hydraulic system.
Turn the boom activation switch to the OFF position.
Stop the engine.
Raise the hood behind the cab in order to access the pilot accumulator.Testing Procedure
Illustration 1 g00682139
Pilot Accumulator
Remove the plug from the bottom of the accumulator. Attach a 0 to 1000 kPa (0 to 145 psi) pressure gauge to the bottom of the accumulator. The indicated pressure on the gauge should be the pressure in Table 2. If the recorded pressure is not correct, perform step 1 through step 6 under "Charging Procedure".Charging Procedure
Install the 224-5152 Adapter in the bottom of the accumulator.
Illustration 2 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