Page 213 of 484

BR-2Braking SystemNotice and Troubleshooting
Notice:
1. Carefully change each part where necessary because any
mistake will affect the brake system properties, and will lead
accidents during driving. And the parts to be changed must
be the same in part number or equal in quality.
2. Keep the parts and each position clean when repairing the
braking system.
Troubleshooting
Trouble Causes Inspection items
Lower or soft pedal Abrasion of brake shoe
Abrasion of brake pad
Oil leakage of braking system
Master cylinder failure
Air in braking system
Wheel-brake cylinder failure
Failure in the automatic regulator of rear brake.Change the brake shoe; Change the brake
pad;
Repair the oil leakage;
Change the master cylinder;
Drain out the air from braking system;
Change the wheel-brake cylinder;
Repair or change the regulator
Brake stagnantPoor adjustment of parking brake;
The bracing wire of parking brake is seized;
Poor adjustment of vacuum booster pushrod)
Failure of the drag spring or the return spring
Pipe line blockage
Brake shoe breakage or deformation
Brake pad breakage or deformation
Seizing of the wheel-brake cylinder or the brake
caliper piston
Automatic regulator breakage
Master cylinder failureAdjust the parking brake;
Make repairing according to real situation;
Adjust the drag rod;
Change the drag spring or the return spring
Make repairing according to real situation;
Change the brake shoe
Change the brake pad
Make repairing according to real situation;
Change the regulator
Change the master cylinder
Over large braking
distanceUnsuitable tire inflation
There is oil stain or lubricant on the brake shoe or
brake pad;
Brake shoe deforms, the brake liner is worn or polished;
Brake pad deforms or is worn or polished;
Brake drum or brake disc deforms
Drag spring or return spring has trouble
The wheel-brake cylinder has trouble
The inner piston of wheel-brake cylinder is seized;
The brake pad is seized;Inflate the air to suitable pressure;
Change the brake shoe or the brake pad;
Change the brake shoe;
Change brake pad
Change the brake drum or the brake disc;
Change the spring;
Change the wheel-brake cylinder;
Change the wheel-brake cylinder
Change the brake pad
The brake pedal is hard
but doesnt work;There is oil stain or lubricant on the brake shoe or
brake pad;
The brake shoe deforms, brake liner is worn or
polished, or the brake wheel is worn;
The brake pad deforms, or is worn or polished;
The piston of wheel brake pump is seized;
The vacuum booster has trouble
The vacuum degree is unsuitable
The brake pipe line is blockedChange the brake shoe brake pad;
Change the brake shoe
Change the brake pad;
Change the wheel-brake cylinder;
Change the vacuum booster;
Make repairing according to real situation;
Make repairing according to real situation;
Page 218 of 484
BR-7
Check and adjust the parking brake
1. Check the stroke of operating lever of the parking
brake to see whether it is correct.
Drag the brake operating lever to the max stroke and count the
grooves it passes.
Stroke of operating lever of parking brake:
Dr(9-10) Teeth
SL SK SY(7-9) Teeth
2. Adjust the parking brake lever where necessary:
Remark: Adjust the rear brake shoe clearance before the
adjustment.
Brake shoe clearance: 0.6mm
(a) Loosen the locking nut and then rotate the adjustable nut
until the stroke is correct, then screw up the nuts.
(b) The brake shoe shall not be stagnant after the adjustment.
Braking SystemInspection and Adjustment
Page 237 of 484

BR-26
Rear brake
Element figure
wheel-brake cylinder cluster
pressure spring drag rod
self clearance-
adjusting bracing
wireparking brake arm
flat washersplit pinbrake shoe gear
return spring
parking brake push plate
push-plate spring back brake
shoe
self clearance-
adjusting toggle
tension spring
brake drum
clearance adjuster
pressure spring seatpressure spring front brake shoe
Disassembly of Rear drum-type Brake
Remark: if the braking torque of manual brake cannot satisfies
the braking requirement, it is suggested to check the thickness
of brake shoe liner, where the thickness is less than the min
thickness, change the brake shoe.
Min thickness1.0mm
1. Tear down the rear wheel;
2. Tear down the brake drum;
Remark: in case the brake drum is not easy to tear down, the
following steps shall be adapted:
(a) Tear down the clearance-adjusting hole; insert a screw-
driver in the brake bottom plate hole to prize up the
adjusting bolt inner tilt angle with the self-adjusting fork.
(b) Use another screwdriver to adjust the adjusting bolt inner
tilt angle to loosen the clearance adjuster of brake shoe. DrBraking SystemRear Brake (Dr)
Parts that cannot be reused after being used
Page 238 of 484
BR-27
3. Tear down the return springs of the two brake
shoes.
4. Tear down the self-adjusting bracing wire, brake shoe
retainer ring, bracing wire guide seat and the self-
clearance adjusting toggle plate.
(a) Press and push the self clearance-adjusting toggle plate to
teardown the bracing wire of self clearance-adjuster,
brake shoe retainer ring and bracing wire guide seat.
(b) Take out the spring from the self clearance-adjusting
toggle plate to tear down the clearance-adjusting toggle
plate and the spring.
5. Tear down the tension spring;
Tear down the tension spring with the pliers.
6. Tear down the brake shoe, clearance adjuster and
parking brake push plate.
(a) Tear down the pressure spring seat, pressure spring and
pressure spring drag rod.
(b) Tear down the brake shoe, clearance adjuster and parking
brake push plate.
(c) Tear down the bracing wire from the parking brake. Braking SystemRear Brake (Dr)
Page 239 of 484
BR-28
7. Tear down the parking brake arm;
Tear down the split pin with pliers to take apart the parking
brake arm.
8. Take apart the brake pipeline from the wheel pump;
Tear down the brake pipeline and block the oil pipe with a clean
cork.
9. Tear down the wheel brake pump;
Tear down the two bolts and the wheel-brake cylinder.
10. Tear down the following bolts and wheel-brake
cylinder parts:
(a) Two piston rod;
(b) Two dust cover
(c) Two pistons
(d) Two piston rubber bows
(e) Spring. Braking SystemRear Brake (Dr)
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BR-31
(d) Adjusting bolts
(e) Contact position where the clearance adjuster and the
brake shoe.
4. Mount the parking brake drag arm;
Mount the new split pin with pliers to mount the parking brake
drag arm.
5. Mount the rear brake shoe:
(a) Mount the parking brake bracing wire on the parking
brake drag arm.
(b) Mount the rear brake shoe in such way that its end is
inserted into the cylinder rod. Encase the pressure spring
drag rod in the brake bottom plate and the brake shoe
assembly in turn and then insert it in the pressure seat ,
pressure spring, pressure spring seat, finally rotate the
pressure spring in place with the pressure spring fork.
6. Mount the parking brake pull plate and the front brake shoe:
(a) Mount the pull plate and the spring.
(b) Mount the front brake shoe, of which, the end is inserted
in the piston rod, and mount the pull plate. Insert the
pressure spring drag rod in the brake bottom plate and
brake shoe assembly in turn, then encase it in the pressure
spring seat, pressure spring and pressure spring, finally
rotate the pressure spring in place with the pressure
spring.
7. Mount the tension spring;
Mount the tension spring with pliers. Braking SystemRear Brake (DR)
Page 244 of 484
BR-33
12. Check the clearance between the brake shoe and the
brake drum:
(a) Tear down the brake drum;
(b) Measure the inner diameter of the brake drum and the
outer diameter of brake shoe to check whether the differ-
ence of the two diameters falls within the standard
clearance range.
Shoe clearance: 0.6mm
If it is not correct, check the parking brake system.
13. Mount the brake drum and the rear wheel; screw up
the nuts of rear wheel hub.
Fastening torque(14510)Nm
14. Fill the liquid container with brake liquid and exhaust
the air in braking system.
15. Check to see whether there is leakage of brake liquid.
Braking SystemRear Brake (DR)
Page 246 of 484
BR-35
4. Tear down the front brake shoe:
(a)Tear down the tension spring from the front brake shoe;
(b) Tear down the pressure spring cap of brake shoe, the
pressure spring and claming pin.
(c) Tear down the lower tension spring from the front shoe
and the shoe pads.
(d) Tear down the lower tension spring from the rear shoe.
5. Tear down the rear brake shoe:
(a) Tear down the shoe pressure spring cap, pressure spring
and claming pin.
(b) Tear down the upper tension spring from the shoe pad.
(c) Tear down the rear brake shoe and the clearance adjuster.
(d) Tear down the parking brake bracing wire from the brake
shoe.
6. Tear down the clearance adjuster from the rear brake shoe:
(a) Tear down the clearance-adjusting spring.
(b) Tear down the clearance adjuster.
Braking SystemRear Brake (SF)