tial case and cross of four side pin鄄
ions, let the left wheel rotate at a dif鄄
ferent speed from the right wheel.
Rear one -piece banjo style axle
housing is made by means of weld鄄
ing punched armor plate.
Assembly & Adjustment
1. Meshing of tooth face and clear鄄
ance adjustment of final drive
1) Check drive pinion bearing for
pretension
The pretightening force of drive pin鄄
ion bearing should be adjusted. Mea鄄
suring in the bolt hole of drive pinion
bearing case, the tangential pull
should be 15~30N.
The pretightening force of drive pin鄄
ion bearing can be adjusted by
means of adding and reducing ad鄄
justing shim. Add shim can decrease
friction torque, while reducing shim
can increase it. There are three kind
of shim according to thickness
(0.10mm, 0.15mm, 0.25mm).
2) Check final drive for meshing be鄄
tween drive pinion and driven gear.
The contact area and side play be鄄
tween drive pinion and driven gear
can be adjusted by means of adjust鄄
ing shim and adjusting collar of dif鄄
ferential bearing. There are three
kind of shim according to thickness,
0.80mm and 0.25mm and 0.10mm,
and the 0.80mm -kind shim should
not be more than one piece. Normal鄄
ly, the clearance between these two
gears is 0.15~0.25mm, while the side
play ranges under 0.07mm. To adjust
side play, measure four points with
equal angle around the driven gear,
and the gauge outfit of micrometer
should be in a vertical position. To
adjust tooth contact area, driven gear
should be coated with red lead at
three points, and 2 ~3 teeth should
coated at every point. Then rotate
gears clockwise and anti -clockwise
to get the trace of contact area (see
the right figure).
Normal trace should be near the
small end, as figure (a); Add shim if
trace near the convex or concave
tooth root, as figure (b); Reduce shim
if trace near convex or concave tooth
top, as figure (c).
36
HFC1020
series trucks
2. Adjustment of differential bearing
Normally, differential bearing should
has pre-torque, and the value is 10~
15N in bolt hole where the left hous鄄
ing of differential fixed to driven gear.
To adjust the pre-torque of differen鄄
tial bearing, adjust the torque of dif鄄
ferential bearing collar. Close the
bearing cover temporarily, then tight鄄
en the bearing cover bolt when the
bearing collar can be tightened and
adjust its pre -torque. The locking
plate should be overlap with the
locking groove, and the driven gear
shouldn't move in axial direction.
Use & Maintenance
1. Lubricate for hyperbola bevel gear
is very strict, can be only specified
gear oil. Don't use or mix with other
gear oil, or will result in quickened
scratch and wear.
2. Don't remove or adjust the gears
and bearings of final drive, for they
have been matched and adjusted in
factory. Do these only when gear
worn and free play is beyond the
limit value, or when bearing axial
clearance is beyond the limit, or
when some of parts damaged.
3. Clean the vent plug regularly,
make sure that ventilation is expe鄄
dite. A jammed air drain can bring
higher air pressure in rear axle, and
it will result in lubricant leak from the
drive pinion seal and other welding
line.
4. Check the lubricant level in axle
housing regularly. Check the lubri鄄
cant for quality regularly, and replace
if the chroma and viscosity is abnor鄄
mal.
Suspension set
General structure
The suspension of this series of
trucks is composed of leaf spring
and bidirectional hydraulic telescopic
trace of contact area between two gears
Convexity
Concave
37