freightliner Argosy COE Maintenance Manual page 63

Frame and Frame Components
31–01 Fifth Wheel Inspection
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. Disconnect the tractor from the trailer. For in-
structions, see Chapter 10 of the Century Class
®
S/T and Coronado
2. Thoroughly steam clean the fifth wheel.
3. Look for cracks in the fifth wheel assembly,
mounting brackets, and mounting parts.
4. Check the jaw and stationary jaw for mushroom-
ing, and check that the serrations at the jaw and
wedge are in good condition.
5. Test the safety lock latch for ease of operation.
NOTE: The safety lock latch is located at the
front of the fifth wheel on the top plate.
6. Visually check for loose nuts or bolts (see
on the fifth wheel and on the mounting. Set a
torque wrench to the maximum torque value for
the bolt being checked, and confirm that the
torque is to specification. Do not loosen the bolt
to check the torque value. See
torque specifications.
7. Visually check all springs to see if they are se-
curely fastened, and are not deformed.
WARNING
Do not disassemble the fifth wheel to inspect the
springs. The springs are under extreme pressure,
and could cause serious injury.
8. Check wedge adjustment.
8.1 Open the kingpin lock, and vertically in-
sert a two-inch-diameter shaft.
Century Class Trucks Maintenance Manual, January 2007
Driver's Manual .
Fig.
Group 00 for bolt
8.2 Release the lock by tripping the release
latch at the bottom of the throat.
8.3 Adjust the wedge stop at the end of the
wedge to approximately 1/4-inch (6-mm)
clearance by turning the wedge stop rod
located on the right side of the top plate.
9. Replace cracked, worn, or damaged parts with
new parts. Replace all loose mounting bolts with
5/8–11 SAE grade 8 bolts, grade C locknuts, and
hardened washers. Do not re-use bolts, nuts,
and washers on fifth wheel mountings.
10. After inspecting the fifth wheel, lubricate all mov-
ing parts with a chassis or multipurpose grease.
Apply a generous coating of grease to the top
plate to fill the grooves, or depressions, on the
top plate. See
for lubrication instructions.
Holland
1. Disconnect the tractor from the trailer. For in-
structions, see the vehicle driver's manual.
2. Thoroughly steam clean the fifth wheel.
3. Check for loose nuts or broken bolts on the fifth
wheel assembly.
4. Inspect for cracks or wear on the mounting bolts.
5. Visually inspect for improper locking action and
for cracks or wear on the jaw locking mecha-
nism.
6. Check the depth of the grease grooves. If the
1)
depth of the grooves is 1/8 inch or less, replace
the fifth wheel top plate. See Group 31 of the
Century Class Trucks Workshop Manual .
7. Check the condition of the X-pattern cast into the
underside of the fifth wheel top plate. See
The fifth wheel top plate must be removed to
check the X-pattern.
7.1 Remove the roll pins from the bushing
pins. Remove the bushing pins from the
slide mount. Using a hoist, lift the fifth
wheel top plate off of the vehicle.
7.2 Turn the fifth wheel top plate over with
the locks open. Check the condition of
the X-pattern in the pockets. If the
X-pattern is worn away, replace the fifth
wheel top plate.
Maintenance Operation 31–02
31
Fig. 2.
31/1