Dongfeng DFA1063DJ10 (14)-301/303. Manual - part 24

Brake System

BR-6

Front Brake

Disassembly

Remove the brake drum and wheel hub assembly, take down the return spring, brake shoe, brake cam, air chamber
bracket and brake bottom plate in sequence.

Check

1.Make sure whether the brake drum is damaged or distorted, replace in necessary.

2.When the brake drum is worn out and becomes out of round, it is allowed to bore, but the accumulative machin-

ing quantity should not exceed 4mm for the diameter direction.

3.When the brake drum assembly has been bored:

The run-out of the drum inside surface to the bearing axis (mm) <0.25

The difference of the inside diameters of left and right drums on one vehicle (mm) <1mm

4.The wear allowance of the lining thickness is 7mm. The distance from the lining surface to the rivet head should

not be less than 1mm. The lining surface should not be cracked and broken away. Otherwise, it should be
replaced.

5.The wear allowance of the shoe flat face at one end should not exceed 0.30mm.

6.Check carefully. There should not be any crack (especially at the two end hooks).

7.The diaphragm of the brake chamber should be in good condition. It should not have any ageing crazing or

crack. It is not allowed to use the same size diaphragms of different hardness on one truck.

8.Check clearance of all fitting surface.

Assembly

1.Install the assembled brake backing plate assembly on the front axle steering knuckle.

Tighten bolts with the specified torque                                   160~220N·m

2.Put the tightening bolts with the locking wires into the holes around the brake camshaft seat from the inside.

Install anchor pin into its seating holes and make two eccentric journals of the anchor pins opposite each other.

3.Assemble brake chamber brackets (with brake chamber assembly) in turn and tighten them. Put in the brake

camshaft and the adjusting washer. Then assemble the front brake slack adjuster on the brake camshaft and lock
it with the cotter pin. The brake air chamber push rod will be connected with the brake adjust arm by a pin.

4.Fit the brake shoes inside the brake backing plate. At anchor pin ends lock brake shoes with lock plate and cot-

ter pins.

5.The return spring is hooked between two brake shoes.

Brake System

BR-7

Adjust

After the brake linings have been replaced, the

brake bottom plates have been dismounted, causing the
positions of the anchor pins and the camshaft changed,
the normal contact of the brake linings and the brake
drum is destroyed; adjust the brake entirely as follows:

1.Take off the cover of the inspection hole on the drum. Loosen the securing nuts of the anchor pins and the nuts

of the securing nuts for the air chamber bracket.

2.Turn the anchor pins to make the marks at their ends opposite each other inwardly.

3.Turn the anchor pins and the worm shaft of the slack adjuster again and again to keep the linings fitted to the

drum fully. At the adjusted position, tighten the nuts of the air chamber bracket and the nuts of the anchor pins.
(Be careful to keep the positions of the anchor pin and the air chamber bracket fixed.)

4.Loosen the worm shaft 1/2~2/3 turn. The drum should rotate freely, but not touch the linings or any other parts.

The clearances between the brake linings and the drum should be:

Near the anchor pins                                             0.25~0.40mm

Near the camshaft                                               0.40~0.55mm

The difference of clearance at the same end of the two shoes                 ≤ 0.1mm

When braking linings worn out and the push rod stroke of the chamber exceeds 40mm, partial adjustment should
be done immediately to reduce the clearance between the linings and the drum. (Never turn the anchor pins to
destroy the good match of linings and drum.) When adjusting, face the worm shaft of slack adjusters, turn the
worm shaft clockwise, clearance decreased, and turn anticlockwise, clearance increased. It is wrong to adjust
clearance by tightening the push rod clevis for changing the stroke of push rod.

Note:
During adjusting the brake clearance, clean up dirt and filth on the head of the adjusting arm worm shaft.

Make use of a double offset ring spanner, cover it onto the worm shaft head, press the lock bush to release the
worm shaft and then turn the worn shaft. If the lock bush can't be pressed down, knock it with a hammer gently
and then press. After adjusting, cover with a rubber dust shield.

Lubricate

1.The brake cam surface

2.Camshaft journal

3.The anchor pins and the holes

4.Brake slack adjust arm assembly

5.Bearing holes of the camshafts on the brake chamber bracket

Brake System

BR-8

Rear Brake

Disassembly

After remove the rear axle half axle, take down the brake drum and wheel hub assembly, then dismount rear

brake adjust arm, brake cam, air chamber bracket, brake shoe with bottom plate assembly, and dust shield in
sequence.

Check

1.Make sure whether the brake drum is damaged or distorted, replace if necessary.

2.Make sure whether the brake shoe with linings is cracked, replace if necessary.

3.Check the roller surface for any cracks and damages, replace if necessary.

4.Check the return springs.

Note:
After replace the friction plate, the excircle of the friction plate needs to be wholly machined. That is to

install the brake shoe and brake bottom plate together, and make use of the bottom plate to position to machine the
excircle of the friction plate.

Assembly

1.Install the brake to the bottom plate, screw on the screw and fasten with steel wire, then machine the excircle of

the brake shoe friction plate.

2.Install the brake shoe and brake bottom plate to the two ends of the rear axle housing, the tightening torque of

the bolt is 130~160N.m, and then install the pressing dust shield.

3.Install the air chamber bracket and fasten, then set to the brake cam and assemble the adjusting spacer. After

that, install the brake adjust arm to the brake cam and lock with a clamp ring, connecting the air chamber push
rod to the brake adjust arm with flat pin.

4.The return spring is hooked between two brake shoes.

Adjust

Disassemble the rubber dust shield of the inspection hole
and the adjust arm. Make use of a double offset ring
spanner to press the lock bush of the worn shaft head,
turn the worm shaft to let the friction plate surface and
inner surface of brake drum contact, then turn worm
shaft loose for 1/2~2/3 circle. At this time, the clearance
between center of two brake shoe friction wafers and
brake drum is about 0.7mm, and the brake drum can turn
freely without interfere with other parts.

After air entered the chamber, the push rod must be out
immediately, and after exhaust, it can return without block. The travel of the air chamber push rod is between 25
±

5mm.

 Lubricate

1.Brake shoe roller shaft

2.Roller hole

3.Roller surface

4.Other parts refer to the front brake

Brake System

BR-9

Frame Brake Pipeline

1.Pipe joint
2.Lock washer with inner tooth
3.Quick release valve set
4.Spring washer
5.Nylon pipe assy
6.Nylon pipe assy
7.Nylon pipe assy
8.Nylon pipe assy 
9.Nylon pipe assy
10.Relay valve assembly technique sets
11.Lock washer with inner tooth
12.Pipe joint

13.Nylon pipe assy--four circuit protective valve
14.All metal lock nut
15.Lock washer with inner tooth
16.Brake hose assy
17.Air pipe assy--three way tube joint to right brake 
air chamber
18.Tube joint--straight
19.2nd air pipe assy--air compressor to unloader 
valve
20.Nylon pipe assy
21.Brake hose assy
22.Air pipe assy--unloader valve to wet air tank