B
BRAKES
Read all of SAFETY and this section before attempting any procedure. Pay particular attention to Notices, Cautions, Warnings and Dangers.
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Repair and Service Manual
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10.
Inspect catch bracket and latch arm.
Replace if showing signs of wear or damage (Ref.
11.
Inspect the park brake kick-off cam.
Inspect for wear and ensure correct adjustment. With
the park brake engaged and fully latched, there must
be no gap between the top of the cam and the latch
arm. Adjust the kick-off cam (3) if required (Ref. Fig.
14). It is very important that the correct setscrews are
used to hold the kick-off cam to the pivot rod. Use of
longer screws prevents correct adjustment of pedal
bumper (pedal travel) and may prevent the brakes
from adjusting properly.
12.
Inspect kick-off cam linkage and bushings.
Check for wear and damage. The kick-off cam pivot
and bushings should move freely and be free of cor-
rosion. The kick-off cam should rotate when the
accelerator pedal is pressed.
Fig. 14 Kick-Off Cam Inspection
Periodic Brake Performance Test (PBPT)
To prevent severe injury or death resulting
from operating a vehicle with improperly func-
tioning brake system, the brake system must
be properly maintained. All driving brake tests
must be done in a safe location with regard for
the safety of all personnel.
The Periodic Brake Performance Test (PBPT) must be
performed regularly (see PERIODIC SERVICE SCHED-
ULE) to evaluate brake system performance. It is useful
as a method of identifying subtle loss of performance over
time and as part of fault diagnosing a problem vehicle.
Before performing this test, inspect the brake pedal and
linkage and correct any problems found including adjust-
ing the brake pedal free travel if required.
The purpose of this test is to compare the braking perfor-
mance of the vehicle to the braking performance of new
or “known to be good” vehicles or to an established
acceptable stopping distance (see below). Actual stop-
ping distances will be influenced by weather conditions,
terrain, road surface condition, actual vehicle weight
(accessories installed) and vehicle speed. No specific
braking distance can be reliably specified. The test is con-
ducted by latching the park brake to eliminate different
pedal pressures and to include the affects of linkage mis-
adjustment. Significant changes or differences in braking
performance will be evident due to mis-adjustment.
Establish the acceptable stopping distance by testing a
new or “known to be good” vehicle and recording the
stopping location or stopping distance. For fleets of vehi-
cles, several vehicles should be tested when new and the
range of stopping locations or distances recorded.
Fig. 15 Periodic Brake Performance Test
Kick-Off Cam
Setscrew
Pedal Latch Arm
Catch Bracket
Cam must be against
latch arm at this point with
no gap.
Latch park
brake and
remove foot
from pedal
Line or Marker
Acceptable
Stopping
Distance
Normal range of
stopping distance
If vehicle requires more
than 4 ft. (1.2 m) beyond
acceptable stopping
distance to stop, or pulls
to one side, it should be
removed from service and
inspected by a qualified
mechanic
Accelerate to
maximum speed
4 ft. (1.2 m)
Line or Marker
Dry, Level, Clean, Paved Surface
