54
Adjusting arm
1冤Lubrication: mount oil month on
adjusting arm, use lithium base
grease periodically to lubricate ad鄄
justing arm (maximum lubrication in鄄
terval is limited to 10000km), or else,
life of adjusting arm will decrease.
2冤Check adjusting arm's counter鄄
clockwise force moment periodically:
rotate adjusting nut of adjusting arm
counterclockwise when running every
20000km and measure whether the
rotary moment is bigger than 18Nm,
measure for three times repeatedly. If
the moment is smaller than 18Nm, it
indicates adjusting arm has been
damage and needs to be replaced
the adjusting arm assembly.
Brake
Front brake has the same structure
with the rear brake. It is shoe brake
with camshaft with fixed sustainer.
When braking, front and rear shoe
slices of the brake press to the rotat鄄
ing brake drum by the action of the
same push force; so the rear brake
shoe is called power-reducing brake
shoe. All above lead to imbalance of
forces that front and rear brake
shoes press on the brake drum, so
this kind of brake is called simple
imbalanced brake.
Clearance between friction disc of the
brake shoe and the brake drum must
be proper, before adjusting the
clearance, make the front wheel off
ground; adjusting steps are as follows:
Full adjustment
1. Loosening fixed nut of brake shoe
bearing pin and nut of binding bolt
on cam bracket.
2. Rotate brake shoe bearing pin so
as to make clearance between front
shoe and bearing pin end the same
as that between rear shoe and bear鄄
ing pin.
3. Start braking, make brake shoe
friction disc lean against brake drum
closely and brake camshaft auto鄄
matic positioned and tighten nut of
binding bolt on support frame.
4. Release braking and rotate worm
so as to make brake shoe friction disc
lean against brake drum closely. Then
counter-rotate worm, released by 3/4r,
brake drum should be rotate freely.
OWNER爷S MANUAL for
HFC1061,HFC1063,HFC1083
series trucks
55
5. Test drive after adjustment, check
working condition of brake, whether
the brake drum get hot and whether
braking distance is proper. If not,
readjust it
Partial adjustment
Turn worm of the brake arm to adjust
clearance between friction disc at the
camshaft end of the brake assembly
and the brake drum. Adjusting meth鄄
ods are as follows: Face to the worm,
turn the worm clockwise, at the same
time, rotate the brake drum come -
and -go continuously till the brake
drum is suppressed completely, and
then return the worm anticlockwise
by 1/2 -3/4 circle, at this time, wind
age of the end of the brake drum
shaft is 0.25-0.4mm, while camshaft
end is 0.45mm.
Brake valve
Brake valve is a mechanism with
which the whole air brake system
controls the brake.
Using and Maintenance:
routine inspection
1. Before running, air pressure in the
pipeline should be checked, when
the air pressure is more than
0.6Mpa, the vehicle can start, and
the normal running air pressure is
0.74-0.84Mpa; if the air pressure is
lower than this value, check the air
pipeline for leak and check whether
the air compressor works normally.
2. Check working condition of the
brake in running whether there is any
trailing or the braking cannot return
and deal with the problems in time. If
the air pressure is lower than
0.45Mpa but the annuciator does not
warn, check the annuciator, replace
it if necessary.
3. If the brake shoe slice is damaged
or over worn, replace for new one;
surface of the new liner should be
grinded, and there should be no oil
dirt, scratches, chap on the surface.
Friction disc must be made of the
same material.
4. Replacing friction disc or rein鄄
stalling shoe slice shaft and brake
camshaft will damage contact condi鄄
tion between former friction disc and
brake drum, because of which, full
adjustment must be done. (see de鄄
tailed adjusting methods above)