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TRUCK SERVICE MANUAL
TM 5-4210-230-14&P-1
AXLES-FRONT
Fig. 5.  Three Stage Operation of Spring Loaded Manual Locking Hub
A later version of the manual type locking chub is the spring-
loaded    type,    Fig.    5,    which    is    designed    to    aid    in    the
engagement  or  disengagement  of  the  front  wheels  with  the
axles.  These hubs overcome the need of moving the vehicle
slightly when the clutch ring does not mesh properly with the
axle shaft hub.
This   spring   in   these   new   hubs   permits   the   control   to   be
positioned in the desired location, and the slight movement of
the  vehicle  will  allow  the  clutch  ring  to  move  into  "LOCK"  or
"FREE" position as selected on the control.
Lock- O- Matic Type
The   Lock-O-Matic   hub,   when   set   in   the   "FREE"   position,
automatically locks the front wheel and axle shaft together the
moment torque is applied to the front axle.  The hub controls,
therefore,  do  not  require  changing  regardless  of  whether  the
vehicle  is  being  operated  in  two  or  four-wheel  drive.    It  is
necessary, however, to set the control in the "LOCK" position
when engine braking control is required (down steep hills, on
ice, etc. ).
OPERATION
Engaging Locking Hubs
To  engage  locking  hubs,  turn  brass  controls  (one  on  each
hub)  clockwise  to  "LOCK"  position,  Figs.  1  and  3.    Arrow  in
center of controls must point directly at dot located on rim of
hub.    You  can  feel  the  brass  control  "seat"  itself  when  it  is
properly positioned.  If the arrow does not point directly at the
dot,  the  control  will  not  seat  itself.    Thus,  the  gears  will  not
completely engage, and the pressure may force off the end of
the hub.  This is only true of hubs that are not spring loaded.
Hubs that are spring loaded allow the control to be positioned
in the engaged location, but engagement of the clutch ring on
the axle shaft hub is not accomplished due to misalignment of
components.    Then  when  the  vehicle  is  moved  slightly,  the
spring-loaded clutch ring will engage with the axle shaft hub,
Fig. 5 Right.
Disengaging Locking Hubs
To 
disengage 
locking 
hubs, 
turn 
brass 
controls
counterclockwise  to  "FREE"  position,  Figs.  2  and  4.    Here,
again,  the  arrow  must  point  directly  at  the  dot  on  the  rim,
otherwise the gears may rake against each other.
The hub on the left side in Fig. 5 illustrates the spring-loaded
type locking hub in the "FREE" position.
When  controls  are  properly  positioned,  gears  are  completely
engaged or disengaged and units will not be damaged.
The  following  CAUTION  hints  may  prevent  damage  to  the
locking hubs:
1.
Use fingers only to turn controls.  If control's do not
move freely with your fingers, move vehicle slightly in
either   direction   in   two-wheel   drive,   standard   gear
range.      If   hubs   do   not   now   turn   freely,   look   for
external  damage  or  dirt  around  brass  controls.    DO
NOT force controls with tools.
2.
DO  NOT  drive  vehicle  unless  controls  on  both  hubs
are properly positioned and both are set the same.
CTS-2209  Page 3
PRINTED IN UNITED STATES OF AMERICA
 
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