BRACKET 1386308 - Caterpillar

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, "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.
Introduction
The following procedure is designed to check the pressure for the front brake differential manifold. The pressure is supplied through a pressure reducing valve on the pilot differential manifold that is located under the cab. This pressure is used to supply all the functions that are on the brake differential manifold. These functions include the service brakes, the front differential lock, and the parking brake.It will be necessary to raise the cab for this procedure.Note: The pressure reducing valve also supply to the rear differential lock.Required Tools
Table 1
Required Tools
Item Description
AA 34475 kPa (5000 psi) pressure gauge Note: Use validated pressure gauges for this testMachine Preparation
Move the machine to level ground. Install the frame lock.
Stop the engine. Parking brake will engage.
Turn the key switch to the ON position. Do not start the engine.
Close the cab door. Press the arming button on the keypad. Depress the pedals and move the joysticks to remove any residual pressure.
Turn the key switch to the OFF position.
Illustration 1 g06100499
Location of the accumulator (parts removed for clarity)
Raise the cab to gain access to the brake accumulator. Refer to the Operation and Maintenance Manual for instructions to raise the cab.
Illustration 2 g02657699
Location of the brake accumulator drain valve on the rear manifold.
Open the brake accumulator drain valve. This action will drain the oil out of the accumulator back to tank. Close the brake accumulator drain valve.Note: Leave the cab in the raised position until the test is complete.Test Procedure Front Brake Manifold
This test procedure requires two people to perform the test.
Illustration 3 g02639656
Illustration 4 g02705978
Location of the Front Manifold
Remove the cover from the front frame.
Illustration 5 g02668779
Location of Pressure Tap
(1) Pressure tap for the front brake manifoldNote: The pressure tap for the front brake is on the front manifold.
Remove the protective cap from pressure tap (1). Connect the 34475 kPa (5000 psi) pressure gauge.
Look at the pressure gauge. Before the engine is started, the oil pressure must be 0. If not, open the accumulator drain valve until the pressure is at 0 and then close the drain valve.
Close the cab door. Start the engine and allow the hydraulic oil to warm to 54° C (130 ° F). Press the arming button to activate the machine functions.
Check the pressure. The front brake manifold pressure should be approximately 11032 kPa (1600 psi).
If the front brake manifold pressure is not correct, follow the procedure to adjust the pressure reducing valve on the pilot differential manifold. If the pressure is correct, shut off the machine. Remove the pressure gauge,