JLG 800A_AJ ANSI Service Manual - Manual (Page 169)

SECTION 3 - CHASSIS & TURNTABLE
3120740 – JLG Lift – 3-113
d. Speed seems to slowly wander (5-15 second
periods) around at speed, particularly at higher
loads. See item 2a. 3 concerning excessive on
Governor.
(3.) Governor not tuned or adjusted for engine/applica-
tion.
The basic adjustment to set sensitivity/stability is the Gain
pot. A good starting point for many engines is full CCW,
then CW 1/3 turn. (See “Governor adjustment” section).
To increase stability, turn CCW. If satisfactory governing
cannot be achieved with this one adjustment, the factory
adjustment may be needed. Normal starting point for this
adjustment is fully CCW, then CW 1/4 turn. (Before chang-
ing this pot, mark the original position).
NOTE: If problems occurs with the Governor overshooting
when a large load is released from the engine, such
as driving up a hill and stopping. There is usually
one of two things:
a. Gain adjustment is to far CCW.
b. Mechanical preload between the carburetor and
actuator is to large, this should be no greater
than 1/2 to 1 ball dia. (Ref. to page 43 par. 1).
Automatic Choke Adjustment Procedure
(For all JLG 1.IL and 2.3L Ford carbureted engines)
1. At 70°F the choke plate should be open 1/3” (not
touching the choke bore).
2. If the ambient temperature is not 7o°F, an additional
adjustment is required:
a. Loosen the three cover plate screws.
b. Adjust the cover to open the choke plate 1/32”.
c. Readjust for ambient temperature by rotating the
cover one (1) mark per 5°F from 70°. Rotate
CCW (lean) if warmer than 70°, CW (rich) if
colder than 70°.
(If actual temperature is 80°, set at 1/32” and
rotate two (2) marks CCW (lean) direction.)
d. Tighten the three cover plate screws and check
for free rotation (no sticking or binding) of the
choke shaft.
3.27 THROTTLE CHECKS AND
ADJUSTMENTS - DEUTZ ENGINE
(PRIOR TO S/N 0300065534)
General
The throttle control system on the Deutz engine includes
the positional controller and the actuator.
Four LEDs are incorporated in the controller. They are as
follows:
• Red - failure: signals a problem with the system -
needs service or adjustment
• Green - clutch engaged; operation normal while sys-
tem is powered.
• Amber - motor extend
• Amber - motor retract
The controller is designed so that when the system volt-
age reaches 10.5 volts, the actuator clutch will be
released and the motor drive turned off in order to prevent
unpredictable operation from occurring.
When a failure condition occurs (i.e. position time-out) the
controller will release the clutch and turn off the actuator
motor. This will prevent unnecessary motor wear.
Table 3-11.Position Controller Truth Table
Control Wiring
Actuator Position
Black Red White Green
GND OFF X X OFF POSITION (Freewheel)
GND +12 VDC OFF OFF POSITION 1 (See Adjustments)
GND +12 VDC +12 VDC OFF POSITION 2 (See Adjustments)
GND +12 VDC OFF +12 VDC POSITION 3 (See Adjustments)
GND +12 VDC +12 VDC +12 VDC POSITION 4 (See Adjustments)
GND = POWER SUPPLY OR BATTERY GROUND
OFF = GROUND OR OPEN CIRCUIT
X = DON’T CARE
+12 VDC = +12 VOLT POWER SUPPLY OR BATTERY SYSTEM, VIA A 5 AMP FUSE
OR CIRCUIT BREAKER
TRIMMER ADJUSTMENTS LED INDICATORS
1 - POSITION 1 CW=RETRACT
2 - POSITION 2 CW=RETRACT
3 - POSITION 3 CW=RETRACT
4 - POSITION 4 CW=RETRACT R - RETRACT INDICATOR (AMBER)
E - EXTEND INDICATOR (AMBER)
C - CLUTCH INDICATOR (GREEN)
F - FAILURE INDICATOR (RED)