with alcohol, if there is no alcohol,
the following steps can be taken:
a. Discharge all the brake fluid, and
fill brake fluid JG3 into the oil reser鄄
voir nearly full for instead, and then
discharge all brake fluid in the
pipeline completely to clean the for鄄
mer brake fluid.
b. Refill the brake fluid according to
specification.
c. After adjusting of the brake system
finishing, free stroke of the brake
pedal should be 8 -12mm, or the
master cylinder will work under ab鄄
normal condition, which will lead to
faults like overheating of the brake
drum.
2.2.1 Service brake
1) Brief description of structure
Service brake adopts hydraulic drum
type, and its front brake and rear
brake adopt double acting leading
shoe type; the service brake is com鄄
posed of brake baseboard, brake re鄄
lease cylinder, brake shoe & liner as鄄
sembly and return spring assembly.
2) Adjusting of the service brake
As the service brake liner is worn
gradually in using, clearance be鄄
tween the liner and the brake drum
increases, it must be adjusted to en鄄
sure braking efficiency. Adjusting is
shown as follows:
Jack up the wheel and take off the
seal stopper, toggle the adjusting
gear of the release cylinder plug ac鄄
cording to arrow direction at base鄄
board adjusting hole side with a
special adjusting screwdriver, at the
same time, rotate the brake drum
come-and-go continuously until the
brake drum is hooped completely,
and then return adjusting gear of the
brake release cylinder plug by 5 -9
teeth to make the clearance between
brake drum and friction disc be 0.2-
0.45mm; after all these, the brake
drum will turn agilely.
3) Using and inspection
After the brake shoe slice is over
worn, it should be replaced for new
one. Surface of the new slice should
be grinded, and there should be no
oil dirt, scratches or chap etc. on the
surface.
Clearance adjusting should be done
in every maintenance class. When
stop the vehicle, touch four brake
drums with hands to check their tem鄄
perature, if the temperature is too
high, readjust the clearance. Seal
condition of the release cylinder
should also be checked regularly, if
there is any oil leak, replace rubber
ring immediately to prevent a series
of faults such as overheating of the
brake drum.
2.2.2. Vacuum power take-off
1) Brief description of structure
2) Vacuum booster equipped to
trucks of HFC1045 series adopts
double diaphragm and is mainly
made up of outer casing return
spring, control valve, rubber film, and
sound damping device etc.
2) Adjusting
The vacuum booster has been ad鄄
justed in the factory; do not disas鄄
semble it in using in case of di鄄
aphragm damage.
渊IX冤Wheel and spare wh -
eel regulator
1. Wheel
1) Brief description
A truck has 7 wheels in all, one of
which is spare wheel and installed
on lower side of the rear frame.
Specification of the tire is 6.50-16 or
6.50R16袁and the air pressure is
about 530Kpa.
2) Using and maintenance
It爷s very important to charge the tire
according to specification, so that a
longer running mileage can be
gained; to run as there is no air or
the air is insufficient is forbidden. It爷s
normal that air temperature of the tire
increases a little in running; to de鄄
crease air pressure by deflating is
forbidden. Check the air pressure in
the tire under cold condition, if size
of the road pattern is proper (two
center prints contact the ground)
when the vehicle is under loading, it
indicates that the tire pressure is nor鄄
mal.
Rust and other sundries on the rims
should be cleaned up when installing
tires, talcum powder had better be
HFC1045
series trucks
60
61