GILLIG LOW FLOOR, Руководство по обслуживанию

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Brakes & Wheels
29
Wheel Inspection
Do not use wheels with bent rims. Such use will result in excessive tire wear and, if used on the front,
steering difficulty may be encountered. If a wheel is suspected of being bent, it should be checked.
1. Remove the wheel from the
coach and dismount the tire.
Clean all rust, scale, and grease
from the wheel.
2. Mount the wheel securely in a
lathe or other suitable fixture
which will allow true circular
rotation.
3. Revolve the wheel slowly and
check at the rim for lateral runout
(wobble), which should not ex-
ceed 3/32" (2.3 mm). See Figure
7- 14 . Check for radial runout
(out-of-round), which also should
not exceed 3/32" (2.3 mm).
Wheels that are distorted in ex-
cess of these tolerances must be
replaced.
Wheels Damage
Cracks running from hand hole to stud hole, bolt hole to center hole, hand hole to hand hole, hand hole
to rim, or stud hole to stud hole are a direct result of overloading or loose wheel nuts. Check the working
loads of axles, check the wheel studs and complete wheel and hub assembly, and scrap the damaged
wheels .
The hub may have a worn mounting face as a result of movement of the inner wheel on the hub. The
studs may have turned in the hub and worn the stud groove or the studs may have actual cracks or breaks
resulting from the abuse. The wheel may have worn ball seats in the stud holes. Each of these possibili -
ties must be checked and all damaged parts replaced.
Rust streaks originating from the stud-holes are a positive indication that the wheel nuts are now, or
have been, loose. In this case the assembly should be checked carefully because damage to hub, studs, or
wheel may have occurred.
Broken or cracked wheel rings are generally caused by rough use of tire tools or improper initial seating
of the ring in the gutter of the rim. When discovered, the ring must be replaced. Bent or sprung rings can
be caused by rough or improper removal of the ring. The damaged ring cannot be properly positioned to
accurately seat in the rim gutter and should be replaced.
Cracks through the side ring, spreading laterally through the entire section, are caused by improper
mounting techniques, impact with road obstructions, and excessive clamping torques on the wheel nuts.
Erosion or chipping of the bead seat of the lock ring is caused by excessive corrosion. Damaged side
rings must be replaced.
Figure 7-14, Distorted Wheel Check
TOP VIEW OF WHEEL
3/32"
3/32"
20-100-x166
RUNOUT
OUT OF ROUND