B
BRAKES
Read all of SAFETY and this section before attempting any procedure. Pay particular attention to Notices, Cautions, Warnings and Dangers.
47
Repair and Service Manual
653045
Figure 8 Brake Pedal Inspection
3.
Check the brake pedal free travel.
Brake pedal free travel refers to the distance the
pedal moves from rest, to the point at which the
brake shoes first contact the brake drums. This
should not be confused with the light resistance that
is felt as the brake pedal is pressed enough to
remove slack from the compensator and cables. Too
much free travel may indicate wheel brakes not
adjusting, wear in the cables and linkages or initial
break-in of components. Not enough free travel can
indicate improper adjustment of the wheel brake or
the brake linkage. Either condition can prevent the
brakes from adjusting properly.
Figure 9 Check Free Travel
The correct brake pedal free travel should be set to 7/8" -
1-1/8" (2.2 - 2.9 cm) (Figure 9).
The parking brake lock force can be checked for verifica-
tion after setting brake pedal free travel. The recom-
mended method of checking parking brake lock force is to
place a ‘bathroom’ scale on the brake pedal. Use both
feet, press the scale down equally against the parking
brake pedal until it latches. The parking brake must lock
between 65 and 75 lbs. (29 - 34 kg) indicated on the scale
(Figure 10). If necessary, adjust the spherical nut to
achieve correct latching pressure.
Figure 10 Checking Parking Brake Latching Pressure
Adjust the brake pedal free travel as described See the
4.
Inspect the brake cables.
Inspect for damage to the outer cable, wear of the
inner cable or no free motion when the pedal is
applied and released. Inspect the brake cable sup-
ports to make sure the cables are correctly secured.
If any of these conditions are found, replace both
cables and equalizer.
5.
Check the clevis pins.
Check the clevis pins that secure the brake cables to
the brake lever. When the brake pedal is released
(Figure 11), the clevis pins must be not loose. If the
clevis pin is not loose, but brake pedal free travel is
correctly adjusted and the brake cables move freely,
the problem may be in the wheel brake.
Part of Frame
Brake
Pedal
Arm
Brake Pedal
Bushing
Front of Vehicle
Pivot
Bolt
Torsion Spring
Floorboard
Measured amount of free travel
Spherical Nut
Loosen Jam Nut
65 70 75
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