JLG 800A Operation And Safety Manual page 59

SECTION 3 - MACHINE CONTROLS AND INDICATORS
13. Steer Select (If Equipped)
When equipped with four wheel steering, the action of the
steering system is operator selectable. The center switch
position gives conventional front wheel steering with the
rear wheels unaffected. This is the best position for normal
driving at maximum speeds. The forward position is for
"crab" steering. When in this mode both front and rear axles
steer in the same direction, which allows the chassis to move
sideways as it goes forward. This can be used for positioning
the machine in aisle ways or against buildings. The back
switch position is for "coordinated" steering. In this mode
the front and rear axles steer in the opposite directions to
produce the tightest turning circle for maneuvering in con-
fined areas. A decal located at top of switch, instructs the
desired wheel maneuver with the switch position.
To re-synchronize the front and rear axles, activate the steer
switch (thumb rocker) until all steer cylinders are at the end
of their stroke. This can be done in either crab or coordi-
nated mode.
3-14
14. Auxiliary Power
When pushed forward, the switch energizes the starter
motor to start the engine.
When pushed back, it energizes the electrically operated
hydraulic pump, when actuated. (Switch must be held ON
for duration of auxiliary pump use.)
The auxiliary pump functions to provide sufficient oil flow to
operate the basic machine functions should the main pump
or engine fail. The auxiliary pump will operate tower boom
lift, tower telescope, main boom lift, main telescope and
swing.
15. Tower Lift
The three position center-off toggle switch provides for rais-
ing and lowering of the tower boom when positioned to
"UP" or "DOWN". TOWER LIFT must be fully elevated "UP"
before operating TOWER TELESCOPE. (TOWER LIFT should
not function when TOWER TELESCOPE is extended).
– JLG Lift – 3121209