YOKE AS 2G8239 - 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).
Personal injury can result from hydraulic oil pressure and hot oil.Hydraulic oil pressure can remain in the hydraulic system after the engine has been stopped. Serious injury can be caused if this pressure is not released before any service is done on the hydraulic system.Make sure all of the work tools have been lowered to the ground, and the oil is cool before removing any components or lines. Remove the oil filler cap only when the engine is stopped, and the filler cap is cool enough to touch with your bare hand.
Sudden movement or accidental starting of the machine can cause personal injury or death to persons on or near the machine.To prevent personal injury or death, perform the following:Park the machine on a smooth, level surface.Lower the work tool to the ground and engage the parking brake.Stop the engine and remove the key.Block the wheels and install the steering frame lock.
Specifications
Note: The pressures in the following table are for an ambient air temperature of 21°C (70°F). Adjust the pressure for other ambient conditions, as required.
Table 1
Accumulator Precharge Pressure/Temperature Relationship for the 5515 kPa (800 psi) Service Brake Accumulators
Temperature Pressure
−7°C (20°F) 5000 kPa (725 psi)
−1°C (30°F) 5100 kPa (740 psi)
4°C (40°F) 5205 kPa (755 psi)
10°C (50°F) 5310 kPa (770 psi)
16°C (60°F) 5410 kPa (785 psi)
21°C (70°F) 5515 kPa (800 psi)
27°C (80°F) 5620 kPa (815 psi)
32°C (90°F) 5720 kPa (830 psi)
38°C (100°F) 5825 kPa (845 psi)
43°C (110°F) 5930 kPa (860 psi)
49°C (120°F) 6030 kPa (875 psi) Introduction
This information includes the following test:
Brake AccumulatorThis information includes the following charge procedure:
Brake Accumulator
Rebuilt Brake AccumulatorTest Preparation
Refer to Testing and Adjusting, "Machine Preparation for Troubleshooting".Refer to Testing and Adjusting, "System Pressure Release".Test Procedure
Illustration 1 g03124729
Move steering frame lock to the LOCKED position.
Stop the engine. Engage the parking brake. Move the transmission direction selector to the NEUTRAL position.
Illustration 2 g03566523
Turn the engine start switch to the ON position. The alert indicator (1) for the brake should come on if the braking system is not at normal operating pressure.
Start the engine. Run the engine at low idle speed until the engine is warm in order to increase the accumulator pressure. The alert indicator (1) should go off.
At low idle engine speed, fully depress the brake pedal and release. Repeat this process until hearing the