edge.
c. Depress the brake pedal several
times before hold it depressed and
release the air-drain screw to bleed.
Repeat doing this until air in tube be
bled completely. Keep a little oil left,
or air can reenter the system.
d. Fill reservoir with brake fluid.
2) Note When Use Brake Fluid
淤 The specified brake fluid of this
series truck is synthetic brake fluid of
class JG3 (GB10830).
于 Never use mixed brake fluid.
盂 Synthetic brake fluid is good at
sopping up. They should be storage
in a clean sealed dry container, keep
away from water, organic solvent,
petroleum, and dust. Otherwise the
vehicle's capability of brake would
be cut down seriously.
榆 Clean system with alcohol before
replacing brake fluid with different
brand. Follow these if alcohol is un鄄
available.
a. After drain all old brake fluid, fill
reservoir with new fluid near to the
opening and bleed system again, in
50
HFC1048
series trucks
schematic diagram hydrostatic
brake system
1. Brake pedal
2.Vacuum booster
and main cylinder assembly
3.Reservoir
4. Connection hose
5.Rear brake
6.Vacuum cylinder
7.Intake manifold 8.Front brake
9. Vacuum check valve
10.Connect to vacuum-alarm
要要
要hydraulic tube
vacuum tube
order to sweep old fluid away.
b. Fill system with brake fluid.
虞 Brake pedal's free play should be
5 ~8mm after adjusted, or it will
cause main booster work abnormally
and make brake drum over hot.
Running brake
1) General Structure
The running brake is hydraulic drum,
both front and rear is two leading
shoe brake. It is composed of bottom
plate, wheel cylinder, brake shoe set
with pad, and return spring set.
2) Adjustment of Running Brake
The clearance between pad and
drum will be bigger and bigger due
to wear. In order to ensure brake
work well, adjust it regularly follow
these steps.
Jack up the wheel which you want to
adjust and remove the seal plug. Dial
the adjusting gear of wheel cylinder
piston accord the arrow near the ad鄄
justing hole on bottom plate with
special adjusting screw and at the
same time rotate the brake drum until
the drum can not rotated by hands.
Then rotate the adjusting gear back
for 5 ~9 teeth, keep the pad 0.2 ~
0.45mm away from the drum, so that
the drum can rotate freely again.
3) Use & Check
Replace the pad which is worn out or
damaged. Before installed, the new
pad should be ground. Make sure
that the new pad has not oil coat, al鄄
so has not crack and chap and other
flaw.
The clearance should be adjusted in
every time of maintenance. Check
drums with hands for temperature ev鄄
ery time you park, adjust the clear鄄
ance if the temperature is too high.
Check wheel cylinders for leak, and
replace the leather gasket if leak is
detected. Protect drums from being
wrong result from over heat and oth鄄
er reason.
Vacuum booster
1) General Structure
Booster of this series of truck is dual
diaphragm vacuum booster, which is
composed of return spring, control
valve, rubber diaphragm, noise elim鄄
ination board, and so on.
2) Adjustment
Booster have been adjusted in fac鄄
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