PLUG 3K0986 - Caterpillar

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.
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.
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
5500 kPa (800 psi) Service Brake Accumulators    
Temperature     Pressure    
-7°C (20°F)    
4980 kPa (720 psi)    
-1°C (30°F)    
5085 kPa (740 psi)    
4°C (40°F)    
5190 kPa (755 psi)    
10°C (50°F)    
5290 kPa (765 psi)    
16°C (60°F)    
5395 kPa (780 psi)    
21°C (70°F)    
5500 kPa (800 psi)    
27°C (80°F)    
5605 kPa (815 psi)    
32°C (90°F)    
5710 kPa (830 psi)    
38°C (100°F)    
5810 kPa (845 psi)    
43°C (110°F)    
5915 kPa (860 psi)    
49°C (120°F)    
6020 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 g02515697
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 g03502389
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 brake charging system recharge the accumulators. When charging, you will hear a slight dip in engine