Western Star 47X 2020, Руководство по обслуживанию

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6. Check the jaw and stationary jaw for mushroom-
ing, and check that the serrations at the jaw and
wedge are in good condition and not fully worn
flat.
7. Test the secondary safety lock latch for ease of
operation.
8. Check for loose nuts or bolts on the fifth wheel
and the mounting. The secondary safety lock,
bumper and operating handle bolts should be
torqued to not more than 80 - 90 N.m (59 - 66
ft-lbs). The wedge stop rod bolt should be
torqued to 4.1 - 20.4 N.m (3 – 15 ft-lbs). 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. For torque specifications,
see
Group 00 of the 47X and 49X Driver’s
Manual.
9. Check all springs to see if they are securely fas-
tened, 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.
10. Check the wedge adjustment.
10.1 Close the fifth wheel on a standard 2-inch
(50-mm) kingpin or similar 2-inch (50-mm)
diameter shaft so that it locks.
10.2 Push on the wedge stop rod with hand
pressure. It should move in 1/4 inch (6
mm) and spring back out on release.
If the free travel is not 1/4 inch (6 mm),
adjust the distance to 1/4 inch (6 mm) by
turning the wedge stop rod, on the right
side of the top plate, clockwise to reduce
the gap and counter-clockwise to in-
crease it.
11. 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.
12. 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. Lubricate grease channels in the top
plate using a lithium complex grease, suitable for
use in high pressure applications. For cold
weather applications, use a less viscous lubricant
such as 90-weight oil, diesel fuel, kerosene,
motor oil, etc. See
MOP 31–02 in this manual for
lubrication instructions.
Jost
1. Disconnect the tractor from the trailer. For in-
structions, see the
47X and 49X Driver’s Manual.
2. Thoroughly steam clean the fifth wheel.
3. Check the mounting for missing or damaged fas-
teners, and broken components. Replace or re-
pair as needed.
4. Inspect the bracket pin bolts. Make sure the lock-
ing tabs are properly securing the bolts in place.
See
Fig. 3 .
5. Check the fifth wheel for bent, worn, or broken
parts. Replace as needed.
6. If the fifth wheel is equipped with low-lube plates,
check the plates and replace if damaged or worn
down to the securing bolts. It is normal for out-
side edges of the plate to pucker slightly; this
does not affect performance.
7. Check the fifth wheel adjustment. Using a lock
tester, lock and unlock the fifth wheel several
times. Make sure that the locking mechanism
works properly.
The lock is properly adjusted if: the wheel locks
and unlocks easily each time and the lock tester
rotates freely.
09/01/2009 f311101
Fig. 3, Bracket Pin Bolt Locking Tabs
Frame and Frame Components
31
47X and 49X Maintenance Manual, August 2020
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