Specifications

SEBU7858-03 113
Maintenance Section
Brakes, Indicators and Gauges - Test
i02444593
Brakes, Indicators and Gaug es
-Test
SMCS Code: 4251-081; 4267-081; 7000; 7450-081;
7490-081
Before you operate the machine, perform the
following c
hecks and make any necessary repairs:
1. Look for broken lenses on the gauges, broken
indicator l
ights, broken switches, and other broken
components in the cab.
2. Start the e
ngine.
3. Look for inoperative gauges.
4. Turn on all machine lights. Check for proper
operation.
5. Sound the forward horn.
6. Move the
machine forward and test the service
brakes. If the service brakes malfunction, consult
your Caterpillar dealer for proper repair.
7. Engage the parking brake.
8. Move th
e machine forward in order to test the
parking brake. If the parking brake malfunctions,
consult your Caterpillar dealer for proper repair.
9. Stop the engine.
i02243154
Braking System - Test
SMCS Code: 4251-081; 4267-081
Service Brake Holding Ability Test
Personal injury can result if the machine moves
while testing.
If the machine begins to move during test, reduce
the engine speed immediately and engage the
parking brake.
Makesurethattheareaaroundthemachineisclear
of personnel and of obstacles.
Testthebrakesonadry,levelsurface.
Fasten the seat belt before you test the brakes.
This test deter
mines whether the service brake is
functional. This test is not intended to measure the
maximum brake holding effort.
g01132855
Illustration 126
1. Start the tractor engine and the scraper engine.
Scroll to Numeric Readout Mode on display area
(1). Look at the air pressure on display area (1).
Allow the brake system air pressure to reach
965 ± 34 kPa (140 ± 5 psi).
2. Disengage the scraper transmission by moving
the scraper transmission neutral/run switch to the
DISENGAGE position.
3. Raise the bowl.
4. Apply the service brake and release the parking
brake.
5. While the engine is at an idle and the service
brake is applied, move the transmission control to
the SECOND SPEED position.
6. Gradually increase the engine rpm. The service
brake should prevent machine movement when
the engine is running at 1200 rpm or less.
If the machine moves with the engine rpm less
than 1200 rpm, consult your Caterpillar dealer for
an inspection of the machine.
7. Reduce the engine speed to low idle and move
the transmission control to the NEUTRAL position.
Engage the parking brake. Lower the bowl to the
ground and stop the engine.
NOTICE
If the machine moved while testing the brakes, contact
your Caterpillar Dealer. Have the dealer inspect and, if
necessary, repair the service brakes before returning
the machine to operation.