LINK 3976723 - Caterpillar

Table 1
Required Tools    
Part Number     Part Description     Qty    
8T-0858     Pressure Gauge     1    This procedure should be followed when the technician is removing a hydraulic line or a hydraulic component.
Personal injury or death can result from escaping fluid under pressure.Escaping fluid under pressure, even a very small pin-hole size leak, can penetrate body tissue and cause serious injury and possible death. If fluid is injected into your skin, it must be treated by a doctor familiar with this type of injury.Always use a board or cardboard when checking for a leak.
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.
Engage the parking brake. Stop the engine.
Illustration 1 g02502976
(1) Right service brake pedal
Depress service brake pedal (1) at least 40 times in order to release oil pressure from the brake accumulators.
Illustration 2 g02502916
Top view location of pressure taps (brake accumulator).
Illustration 3 g01150449
(2) Pressure tap for rear brake accumulator oil (3) Pressure tap for front brake accumulator oil
Connect an 8T-0858 Pressure Gauge to pressure tap (2). Check the reading on the 8T-0858 Pressure Gauge. The pressure gauge should read 0 kPa (0 psi) when the service brake pedal is depressed.
Connect an 8T-0858 Pressure Gauge to pressure tap (3). Check the reading on the 8T-0858 Pressure Gauge. The pressure gauge should read 0 kPa (0 psi) when the service brake pedal is depressed.
If the pressure on any of the gauges does not read 0 kPa (0 psi), repeat Steps 2 through 5.