MECHANICAL BRAKES
Page M-15
Repair and Service Manual
Read all of Section B and this section before attempting any procedure. Pay particular attention to all Notes, Cautions and Warnings.
B
B
Fig. 18 Free Travel Adjustment
The correct brake pedal free travel should be set to 7/8"
- 1 1/8" (2.2 - 2.9 cm).
Press the brake pedal aggressively 4 - 6 times to estab-
lish 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
aggressively. As the brakes 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 (Ref. Fig. 19 on
Page M-15). If they are not loose, inspect system again
and correct as required. If the clevis pins are loose,
tighten jam nut to 10 - 11 ft. lbs. (14 - 15 Nm) at the
spherical nut
.
Fig. 19 Check Clevis Pins
The parking brake latching force can be checked as ver-
ification after setting brake pedal free travel. To check
parking brake latching force, place a ‘bathroom’ scale on
the service and parking brake pedals. Using both feet
press the scale down against the parking brake pedal
until it latches. The parking brake should latch between
65 and 75 lbs. (29 - 34 kg) indicated on the scale (Ref.
Fig. 20 on Page M-15).
Fig. 20 Checking Parking Brake Latching Pressure
Perform the Periodic Brake Performance Test as
described and return the vehicle to service if brake per-
formance is satisfactory.
Spherical Nut
Jam Nut
7/8" - 1 1/8" (2.2 - 2.9 cm)
Clevis Pin Loose?
If required adjust spherical nut
to achieve correct parking brake
latching pressure of 65 - 75 lbs.
(29 - 34 kg).
Loosen Jam Nut
Use a 'bathroom' scale
to confirm the latching force
required to engage and latch
the parking brake.
65 70 75