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, 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 effects of "bedding in" (or seating). When
checking torque, torque the nut, not the bolt head
whenever possible. This will give a true torque read-
ing by eliminating bolt-body friction. When checking
the torque of frame fasteners, inspect 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.
Refer to
Group 00
of the vehicle Workshop Manual
for torque specifications.
NOTICE
Make sure frame fasteners are properly tightened.
Continued vehicle operation with loose fasteners
could result in bracket or frame damage.
Check the fasteners at the following locations:
•
Axle Stops
•
Deck Plates
•
Equalizer Brackets
•
Exhaust Brackets
•
Fifth Wheel Legs
•
Fifth Wheel Mountings
•
Frame Crossmembers and Gussets
•
Front Frame Brackets
•
Front Suspension Spring Brackets
•
Fuel Tank Brackets
•
Radius Rods
•
Rear Suspension Spring Brackets
•
Shock Absorbers
•
All Other Frame Fasteners
Any component that shows signs of cracking or other
damage must be repaired or replaced. Refer to the
vehicle vehicle Workshop Manual for repair or re-
placement information.
31–02 Fifth Wheel Inspecting
WARNING
All fifth wheel maintenance, adjustment, and re-
building must be done only by a qualified me-
chanic. Improper or incomplete procedures could
result in a possible disengagement of the trailer
from the tractor, which could result in personal
injury or property damage.
Parts are under spring compression. Wear safety
goggles while servicing the fifth wheel. Failure to
do so can result in personal injury, due to parts
ejecting with force.
Fontaine
1.
Using a degreaser, clean the fifth wheel and
mounting brackets.
2.
Inspect for cracks in the fifth wheel assembly, the
mounting brackets, and mounting components.
3.
Inspect for wear and damage to moving parts.
4.
Check for loose nuts and bolts in the fifth wheel
and mounting hardware. Tighten nuts and bolts
as necessary.
5.
Check the wedge adjustment.
5.1
Close the fifth wheel on a standard 2-inch
(50-mm) kingpin or similar 2-inch (50-mm)
diameter shaft so that it locks.
Frame and Frame Components
31
Business Class M2 Maintenance Manual, March 2016
31/1
Property of American Airlines
