The lock is properly adjusted if: the wheel locks
and unlocks easily each time and the lock tester
rotates freely.
The lock is too loose if: you feel fore-aft play
when pulling and pushing on the lock tester
handle. See
Fig. 6, Ref. A.
The lock is too tight if: the lock tester does not
rotate freely in the lock. See
Fig. 6, Ref. B.
8. If the lock is improperly adjusted, correct as fol-
lows.
If the lock is too tight, loosen the jam nut, turn
the adjustment bolt clockwise one full turn, then
reset the jam nut. Lock and unlock the mecha-
nism several times to test. Repeat if necessary.
See
Fig. 7.
If the lock is too loose, loosen the jam nut, turn
the adjustment bolt counterclockwise one full
turn, then reset the jam nut. Lock and unlock the
mechanism several times to test. Repeat if nec-
essary. See
Fig. 7.
9. If the fifth wheel is equipped with a sliding
mechanism, inspect and adjust it as follows.
9.1 Check the bracket for any cracks or miss-
ing and damaged parts.
9.2 Inspect the locking plungers for full en-
gagement.
9.3 Check the locking mechanism for proper
operation.
If the plungers will not release, check the
air cylinder or plunger adjustment.
If the plungers are loose, check the
plunger adjustment and the plunger
springs for proper compression. Replace
if needed.
09/01/2009 f311101
Fig. 5, Bracket Pin Bolt Locking Tabs
09/01/2009
f311099
A
B
C
D
E
F
G
H
A. Checking for fore/aft play.
B. Rotating tester in lock.
C. Engage hook.
D. Pull/push handle fore/aft.
E. Check for movement of kingpin in lock.
F. Disengage hook.
G. Push/pull handle inboard/outboard.
H. Rotate lock tester.
Fig. 6, Jost Fifth Wheel Adjustment
Frame and Frame Components 31
108SD and 114SD Maintenance Manual, May 2018 31/5
To Next Page
Loading...
