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
634756
Brake Pedal and Linkage Inspection
1.
Inspect brake pedal return bumper.
Ensure that the pedal is contacting the return bum-
per when released, that the bumper is in good condi-
tion and that a 1/4 - 3/8" (6 - 9.5 mm) gap exists
between the pedal arm and the setscrew heads of
the kick-off cam (Ref. Fig. 7). Replace or adjust the
bumper if required. “Pedal Bumper Adjustment” on
Fig. 7 Brake Pedal Bumper Inspection
2.
Check brake pedal return.
Apply the brake pedal and release. Check that the
brake pedal arm rests against the return bumper
when released. Check that the torsion spring is
hooked around both the pedal and the frame and is
in good condition. If the pedal does not return fully or
is sluggish, the brake pedal bushings and pivot bolt
should be inspected (Ref. Fig. 8). Replace pedal,
spring, bushings and bolt as required. “Brake Pedal
Removal and Installation” on page 82
Fig. 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 may
indicate improper adjustment of the wheel brake or
the brake linkage. Either condition can prevent the
brakes from adjusting properly.
Fig. 9 Check Free Travel
The correct brake pedal free travel should be set to 7/8" -
1-1/8" (2.2 - 2.9 cm) (Ref. Fig. 9).
The park brake latching force may be checked as verifica-
tion after setting brake pedal free travel. The preferred
method of checking park brake latching force is to place a
‘bathroom’ scale on the service/park brake pedal. Use
both feet to press the scale down evenly against the park
brake pedal until it latches. Latching should occur
between 65 and 75 lbs. (29 - 34 kg) as indicated on the
scale (Ref. Fig. 10). If necessary, adjust sperical nut to
achieve correct latching pressure.
Fig. 10 Checking Park Brake Latching Pressure
1/4" - 3/8" (6 - 9.5 mm) diameter
drill or bolt must pass
through tap.
Adjust at bumper if needed.
Pivot
Bolt
Brake
Pedal Bushing
Torsion Spring
Brake
Pedal
Arm
Part of
Frame
Floorboard
Measured amount of free travel
Spherical Nut
Loosen Jam Nut
65 70 75