Cushman MINUTE MISER, Руководство по ремонту и обслуживанию техника

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BRAKES
Page J-2
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
The mechanic should perform a ‘panic stop’ by applying
maximum force and travel to the service brake pedal
while moving at full speed. If one wheel fails to lock, it is
reasonable to expect that a problem exists with the ser-
vice brake system and a complete brake maintenance
(described elsewhere in this section) must be performed.
Test the vehicle before returning it to service.
SIX MONTH BRAKE SYSTEM
MAINTENANCE
Raise the entire vehicle (as specified in Section B -
Safety).
Rotate each rear wheel by hand. Feel for a dragging
brake shoe that prevents smooth movement of the wheel
and brake drum.
Remove the clevis pin from brake straps where it is
attach to the wheel brake levers
Again rotate each wheel by hand and feel for a dragging
brake shoe that prevents smooth movement of the wheel
and brake drum. If the wheel rotates more smoothly than
with the brake strap attached, an out of adjustment brak-
ing system is indicated and
must be repaired.
Inspect the brake strap for damage. A damaged brake
strap will result in the system dragging. Any worn out
strap
must be replaced. Operate the brake pedal and
observe the movement of the strap. Both should move
the same amount and return fully when the brake pedal
is released. If the brake pedal does not return to the full
upright position, excess pedal bushing friction is indi-
cated or a system is in need of service. The bushing
must be removed and lubricated or replaced. Observe
the equalizer bar to see if it pivots during operation of the
brake pedal. A pivoting equalizer bar, uneven movement
or failure of the brake strap to return fully indicates a
dragging brake system which
must be repaired.
Remove each brake drum and shoes according to proce-
dures indicated in
BRAKE DRUM REMOVAL and
BRAKE SHOE REMOVAL sections. Clean and inspect
all brake parts. If there is evidence of rust or if the lever
slide mechanism does not move smoothly in the backing
plate, the surfaces must be cleaned and smoothed using
an emery cloth. The backing plate
must be replaced if
excessive wear such as gouges or galling are in evi-
dence on the backing plate.
HOW THE SERVICE BRAKE WORKS
Fig. 2 Brake Pedal
Depressing the service brake pedal pulls the equalizer
link. The first part of the pedal travel removes slack from
the system. Continued motion of the brake pedal pulls a
brake lever which pushes the rear brake shoe against
the brake drum. When the rear shoe contacts the brake
drum, it can no longer move rearward. Additional pedal
travel causes the actuator bracket (moving anchor) to
move and applies force to the front shoe, pushing it
against the brake drum. The force applied to the front
and rear shoes is approximately equal. As the shoes
contact the moving brake drum, the shoes try to move in
the direction of drum rotation. This movement results in
the typical brake shoe wear patterns.
Equalizer Link
The equalizer link balances braking between the driver
and passenger sides of the vehicle. Variations in wheel
brake adjustment, strap friction and manufacturing toler-
ances may cause the equalizer to be slightly misaligned.
This misalignment is normal.
Automatic Adjuster Mechanism
Never manually adjust the
brakes at the star wheel. Doing
so will cause permanent damage to the adjuster
assembly and result in a gradual loss of brakes.
The wheel brakes are equipped with an automatic
adjuster mechanism that is designed to compensate for
brake shoe wear and eliminate the need for manual
brake shoe adjustment. Do not manually adjust the
brakes by prying back the adjuster arm and turning the
star wheel. Permanent damage to adjuster will result
Adjustment takes place only when the brake is fully
applied and released while the vehicle is moving (Ref
Fig. 3 on page J-3). It is very important that the brake
LATCH ARM
BRAKE PEDAL
EQUALIZER L