Thomas SAF-T-LINER C2, Руководство по обслуживанию

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31–00 Safety Precautions
Safety Precautions in this section apply to all
procedures within this group.
DANGER
When working on the vehicle, shut down the en-
gine or motor, set the parking brake, and chock
the tires. Before working under the vehicle, always
place jack stands under the frame rails to ensure
the vehicle cannot drop. Failure to follow these
steps could result in serious personal injury or
death.
31–01 Frame Fastener Torque
Check
Frame brackets and components secured with Huck-
bolt® fasteners do not require a torque check, how-
ever, they should be inspected for damage. Frame
brackets and components secured with conventional
bolts and nuts are to be checked at initial mainte-
nance (IM).
Check the torque of frame fasteners to offset the ef-
fects of bedding in or seating. When possible, always
check the torque of the nut, not the bolt head. This
will give a true torque reading by eliminating bolt
body friction.
When checking the torque of frame fasteners, in-
spect the frame for cracks and other damage. Set a
click-type torque wrench to the maximum torque of
the fastener you are checking. Apply pressure until
the torque wrench clicks. Do not loosen the bolt to
check the torque. For torque values, see the appli-
cable torque table in
Group 00 of the vehicle Mainte-
nance Manual .
NOTICE
Make sure frame fasteners are properly tightened.
Continued vehicle operation with loose fasteners
could result in bracket or frame damage.
NOTE: Engine supports on vehicles built from
January 2007 require the same maintenance as
shown below.
Inspect the fasteners at the following locations:
•
axle stops
•
engine trunnion supports
•
exhaust brackets
•
frame crossmembers and gussets
•
front frame brackets
•
front suspension spring brackets
•
fuel tank brackets
•
radius rods
•
rear engine supports
•
rear suspension spring brackets
•
shock absorbers
•
all other frame fasteners
Any component that shows signs of cracking or dam-
age must be repaired or replaced. See the applicable
group in the vehicle
Workshop Manual for repair or
replacement information.
31–02 Automatic Tire Chain
System Checking
IMPORTANT: The system check should be com-
pleted every 500 hours of truck operation.
1. Check all nuts and bolts and make sure they are
tight.
2. Grease the chain wheel bearings and arm bear-
ings to prolong their life.
3. Check the chain wheel bearings and arm bear-
ings for play.
4. Inspect the chain links for wear. Make sure there
are at least nine links for 190 mm wheels and
seven links for 170 mm wheels.
5. Engage the tire chain system and check for air
leaks.
6. Check the chain wheel pressure against the tire.
It should be at least 20 lbs (9 kg).
7. Drain any water out of the air tank to keep the
air lines free of dirt and water. Excess dirt and
water may damage the solenoid valve or cause
premature wear.
8. Actuate the solenoid valve to keep it clean and
functioning correctly.
Frame and Frame Components
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Saf-T-Liner C2 School Bus Maintenance Manual, June 2015
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