PREVOST X3-45 2016, Руководство по обслуживанию

Страница: 259 / 459

Section 13: WHEELS, HUBS & TIRES
PA1593
3
2. Loosen wheel nuts about one turn (do not
remove the nuts). This is not necessary if
equipped with hydraulic powered gun.
3. Raise the vehicle by its jacking points on the
body. See Section 18,
"Body", under heading
"Vehicle Jacking Points";
4. Unscrew wheel hex stud nuts and remove
the wheel;
CAUTION
Always mark position of the wheel on the axle
prior to removal in order to replace wheel at
the same location, thus avoiding a new wheel
balancing.
2.3 SINGLE WHEEL INSTALLATION
1. Mount the wheel over studs, being careful
not to damage stud threads;
2. Screw in the hex stud nuts (refer to Figure 2
for sequence) so that wheel will position itself
concentrically with hub. This is important,
otherwise wheel may be eccentric with hub
and will not run straight. In this initial step,
slightly tighten the nuts to correctly position
the wheel;
3. Tighten stud nuts progressively as shown in
Figure 2. The final tightening should be done
with a torque wrench. Tighten stud nuts to
450 - 500 lbf-ft (610 - 680 Nm) for all steel
wheel.
CAUTION
Insufficient mounting-torque can result in
damage to parts. Excessive mounting torque
can cause studs to break and the wheel to
crack in stud hole area.
3. DUAL WHEELS
3.1 OUTER WHEEL REMOVAL
Same as described in "Single Wheel Removal"
procedure described previously.
3.2 INNER WHEEL REMOVAL
1. Remove outer wheel;
2. Remove inner wheel.
3.3 INNER WHEEL INSTALLATION
Mount the wheel over studs, being careful not to
damage stud threads;
3.4 OUTER WHEEL INSTALLATION
With inner and outer wheels installed, tighten
the stud nuts progressively as shown in Figure
2. The final tightening should be done with a
torque wrench. Tighten stud nuts to
450 - 500 lbf-ft (610 - 680 Nm) for all steel
wheel.
CAUTION
Insufficient mounting-torque can result in
damage to parts. Excessive mounting torque
can cause studs to break and the wheel to
crack in stud hole area.
NOTE
On dual wheel assemblies, position the
wheels with the tire valves 180º apart in order
to have access to both the inner and outer
valves.
3.5 INSPECTION
1. Loosen a hex stud nut three turns (Fig. 4);
2. Retighten the hex stud nut to 450 - 500 lbf-ft
(610 - 680 Nm).
Repeat for each of the 10 "hex stud nuts"
according to the tightening sequence in figure 2.
CAUTION
The actual length of thread engagement
present in an assembled wheel can not
always be determined by visual inspection of
measurement of a tightened assembly. The
relationship of the wheel cap nut seat to the
end of the stud may vary. If there is any doubt
that enough thread engagement is present,
the number of engaged threads may be
counted. Tighten all nuts in the regular
manner, then loosen one to hand-tightness.
The number of turns to disengage a 1-1/8-inch
nut should be at least five full turns.
At least seven full turns should be required to
disengage a ¾-inch nut or a M22 nut. Ideally,
when torqued to the proper load, the stud
should be flush with the face of the nut. The
face of the nut may be recessed in nuts that
are taller for improved wrenching. With most