4
EVERY 3 MONTHS, 25,000 MILES OR 900 OPERATING
HOURS
1. Remove any accumulated contaminants such as dirt
and gravel from the heel of the pedal, plunger, plunger
boot, and mounting plate.
2. Using a light oil, lubricate the pedal roller, roller pin, and
hinge pin.
3. Inspect the plunger boot for cracks, holes, or
deterioration. Replace if necessary. Also check mounting
plate and pedal for wear and corrosion. Repair or replace
as necessary.
4. Apply 2 to 4 drops of oil between plunger and mounting
plate - DO NOT OVER OIL!
5. Check for excessive leakage as described in the
“OPERATIONAL & LEAKAGE TEST” section of this
manual.
EVERY YEAR, 100,000 MILES, OR 3,600 OPERATING
HOURS
1. Perform steps 1 through 4 above.
2. Perform the checks in the “OPERATION & LEAKAGE
TEST” section of this manual.
OPERATIONAL & LEAKAGE TESTS
GENERAL
A change in vehicle braking characteristics or a low pressure
warning may indicate a malfunction in one of the brake
circuits. Although the air brake system may continue to
function, the vehicle should not be operated until the
necessary repairs have been made and both braking circuits,
including the pneumatic and mechanical devices, are
operating normally.
If the brake valve does not function as described above or if
leakage is excessive, it is recommended that it be replaced
with a new or remanufactured unit, available at Bendix outlets.
Always check the vehicle brake system for proper operation
after performing brake work and before returning the vehicle
to service.
OPERATIONAL TEST
Check the delivery pressure of both circuits, using test
gauges known to be accurate. Note: The pedal will not be in
a “normal” released position until the air brake system is
pressurized. The pedal will rise to its normal release position
as the brake system is pressurized from 0 psi. Depress the
pedal to several positions between the fully released and
fully applied positions and check the delivered pressure on
the test gauges to see that it varies equally and proportionally
with the movement of the brake pedal.
FIGURE 6 - APPLYING-FAILURE IN THE SECONDARY CIRCUIT
PEDAL
FORCE
PLUNGER
FORCE
SUP-1
SUP-2
EXHAUST
DEL-1
DEL-2
DEL-1
FIGURE 7 - BALANCED POSITION
PLUNGER
FORCE
SUP-1
PEDAL
FORCE
SUP-2
EXHAUST
DEL-1
DEL-2
DEL-1
AIR FLOW
á
AIR FLOW
á
