PLATE-WASHER 4196748 - Caterpillar

Escaping fluid under pressure, even a pinhole size leak, can penetrate body tissue, causing serious injury, and possible death. If fluid is injected into your skin, it must be treated immediately by a doctor familiar with this type of injury.Always use a board or cardboard when checking for a leak.
Personal injury or death can result if two persons are not used in the following procedure.
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, "Caterpillar Dealer Service Tool Catalog" for tools and supplies suitable to collect and contain fluids on Caterpillar products.Dispose of all fluids according to local regulations and mandates.
"Procedure 1" is a quick method for checking the cutout pressure. This procedure also indicates whether the brake accumulator pressure switch and the brake oil pressure indicator operate correctly. The procedure provides an estimate of the accumulator precharge pressure and an estimate of the number of brake applications before the brake oil pressure indicator turns on."Procedure 2" determines whether the cut-in pressure and the cutout pressure are correct. This procedure also provides the required steps for adjusting the brake accumulator charging valve.Procedure 1
Stop the engine. Engage the parking brake. Depress the brake pedal until there is no brake oil pressure.
Illustration 1 g01199201
Location of Accumulator Charging Valve and Pressure Taps (1) Pressure tap for rear service brake accumulator. (2) Pressure tap for the front service brake accumulator. (3) Accumulator charging valve. (5) Cover for adjustment screw.
Connect a 0 to 20700 kPa (0 to 3000 psi) pressure gauge at pressure tap (2) for the front service brake accumulator on brake accumulator charging valve (3) .
Observe the pressure gauge. Before the engine is started, the oil pressure must be 0 kPa (0 psi).
Start the engine. Allow the oil pressure to increase to the cutout pressure. The correct cutout pressure should be 14485 345 kPa (2100 50 psi).
After the brake accumulators have been completely charged and the correct cutout pressure has been obtained, stop the engine.
Turn the engine key start switch to the ON position, but do not start the engine.
Apply the service brakes repeatedly. Pause for two seconds before each brake application and count the number of applications while you observe the pressure gauge.
Illustration 2 g01199208
Instrument Cluster (4) Low oil pressure indicator for the brake system.
When the reading on the pressure gauge decreases to 8960 345 kPa (1300 50 psi), brake oil pressure indicator (4) will turn on. This indicates the operational status of brake oil pressure indicator (4). This also indicates the operational status of the brake accumulator pressure switch.
Continue to apply the service brakes. Pause for two seconds before each brake application. When the pressure drops off rapidly, this indicates the approximate nitrogen precharge pressure in the brake accumulators.
Determine the number of brake applications that were required before the sudden pressure drop