B
52
Repair and Service Manual
BRAKES
Read all of SAFETY and this section before attempting any procedure. Pay particular attention to Notices, Cautions, Warnings and Dangers.
653045
Adjusting Brake Pedal Free Travel
Brake pedal free travel must be
checked and adjusted any time the
brake system is serviced, or when
parts are replaced.
Brake pedal free travel refers to the distance the pedal
travels from rest to the point at which the brake cables
start to move the brake levers. This should not be con-
fused with the light resistance felt as the brake pedal is
pressed enough to remove slack from the compensator
and cables. Correct adjustment of free travel is essential
to proper brake function. Excess free travel will limit brak-
ing capability; insufficient free travel may cause the
brakes to drag (not fully release). Either condition can
prevent the brakes from adjusting properly.
The purpose of this procedure is to
adjust the brakes and seat brake
system components. The brake sys-
tem cannot be effective for the first few applications
of the brake pedal.
Pre-adjust brake pedal free travel to the correct setting by
loosening the jam nut and adjusting the spherical nut
(Figure 18). Tighten the jam nut to the torque value speci-
fied below.
Figure 18 Free Travel Adjustment
The correct brake pedal free travel is 7/8" to 1-1/8" (2.2 to
2.9 cm).
Press the brake pedal aggressively four to six times to
establish known free travel.
All brake tests must be done in a
safe location with regard for the
safety of all personnel.
In a safe location, free from people and vehicles, drive the
vehicle at reduced speed and apply the brakes aggres-
sively. As the brakes begin to adjust and stop the vehicle
effectively, start driving at maximum speed and brake
aggressively 10 times.
At the spherical nut, adjust the free travel as noted above.
Drive again and brake aggressively 10 times.
Repeat the previous step(s) until the pedal free travel
does not change during the aggressive braking.
Check to see that the clevis pins attaching the brake
cables to the brake levers are loose (Figure 19). If they
are not loose, inspect the system again and correct as
required. If the clevis pins are loose, tighten the jam nut at
the spherical nut to the torque value specified below.
Figure 19 Check Clevis Pins
The parking brake latching force can be checked as verifi-
cation after setting brake pedal free travel. To check the
parking brake latching force, place a bathroom scale on
the brake pedal. Use both feet to press the scale down
against the parking brake pedal until it latches. The park-
ing brake should latch between 65 and 75 lbs. (29 - 34 kg)
indicated on the scale (Figure 20).
Perform the Periodic Brake Performance Test as
described and return the vehicle to service if brake perfor-
mance is satisfactory.
Item
Torque Specification
Jam Nut
10 - 11 ft. lbs. (14 - 15 Nm)
Spherical Nut
Jam Nut
7/8" to 1-1/8" (2.2 to 2.9 cm)
Item
Torque Specification
Jam Nut
10 - 11 ft. lbs. (14 - 15 Nm)
Check for loose
clevis pin
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