31
lowed, or else, it can result in the
disability of the pedal尧 deficiency of
the effective travel and incomplete
release of the clutch etc. So the
clutch can not work normally. The
work of air bleeding should be com鄄
pleted by two persons in the best,
one person depress the clutch pedal
in the cab, the other bleed the air in
the wheel cylinder. The schematic
diagram of air bleeding for the clutch
wheel cylinder is shown .
Take off the rubber cap of the air
bleed screw on the wheel cylinder,
link a plastic pipe on the air bleed
screw, put the other end of the pipe
into the container filled with brake
fluid, depress the clutch pedal sever鄄
al times, fill the master cylinder and
hydraulic pipeline with brake fluid,
then loosen the air bleed screw, air
bubble can be puffed from the oil
ring if there have air in the pipeline.
Repeat the above-mentioned opera鄄
tion until the air bubble disappear .
Maintenance and adjustment
Long time use or incorrect adjust鄄
ment and incomplete air bleeding of
the clutch can bring the halfway re鄄
lease of the clutch, let the clutch on
the half contact state for long time,
aggravate the wear of the clutch
pressure plate and friction linings.
The decrepitation尧 burnt and exfolia鄄
tion of the friction lining, and the
burnout of the release bearing also
can result in the abnormal operation
of the clutch. When maintenance, all
kinds of clearance of the clutch must
be adjusted. When doing the third
maintenance for the trucks ,you must
clean general/dispant cylinder and
liquid reservoir tank ,then fill grease
to hole of disengaging shaft.
1尧release fork
2尧dust cover
3尧copper washer 4尧wheel cylinder
5尧wrench
6尧soft plastic pipe
7尧container
8尧braking
渊玉冤Clutch
1.Brief description of the struc鄄
ture
The clutch equipped for this series
truck is single -plate dry type di鄄
aphragm spring clutch, outside di鄄
ameter of the driven plate is 椎254.
The hydraulic control unit of the
clutch is composed of the clutch
pedal尧oil storage cup尧 release cylin鄄
der (master cylinder)尧 wheel cylinder
and oil pipe. It is shown in the below
figure.
Adjustment of the clutch operat鄄
ing system
1冤Adjust the limit screw of the clutch
pedal (below figure) to make sure
that the free play of the pedal is 3耀
5mm.
2冤Adjust the mas ter cylinder of the
clutch: loosen the locknut on the
push rod of the master cylinder, ro鄄
tate the end of the push rod to con鄄
tact gently the with piston of the
master cylinder, then rotate the push
rod for 3/4 circle in the contrary di鄄
rection, tighten the locknut of the
push rod, now the clearance be鄄
tween the push rod and the piston is
about 0.5耀1mm.
3冤Adjust wheel cylinder of the clutch
Take off the return spring of the re鄄
lease fork, push the wheel cylinder
piston to the bottom of the cylinder,
loosen the locknut on the push rod,
push the release fork towards the
backside of the engine to the posi鄄
tion where the release bearing and
the release fork contact barely, turn
the spherical nut until it contacts with
the release fork, then turn back the
spherical nut on the push rod for 3
circles, tighten the nut, install the re鄄
turn spring of the release fork.
4冤Bleed air from wheel cylinder of
the clutch
Having air or oil leakage in the hy鄄
draulic pipeline of the clutch is unal鄄
clutch pedal
30
HFC1048
series trucks