JLG 800A_AJ Service Manual - Manual (Page 237)

SECTION 4 - BOOM & PLATFORM
3120858 – JLG Lift – 4-23
Dual Capacity Angle Limit Switch (800A
only)
NOTE: The boom position and location of the Upper Boom
Dual Capacity Switch requires a working surface 20
ft. high to safely check and adjust the switch.
1. Place machine on level surface.
2. From platform control, with less than 500 lbs. (227
kg) in platform.
3. Raise tower boom to maximum angle. Extend upper
boom until the capacity indicator lights change from
1000 lbs. (454 kg) to 500 lbs. (227 kg).
4. With upper boom length in this position, raise the
upper boom until the indicator lights change back to
the 1000 lbs. (454 kg) indicator.
5. The Dual Capacity Limit Switch, located at the tele-
scope cylinder of the Upper Boom, (See Figure 4-
12.), will activate the 1000 lb. light when the upper
boom is at 56 to 61 degrees.
NOTE: Place angle indicator on main base boom at least 2
ft. from pivot pin.
6. Lower upper boom until 500 lb. light comes on. The
boom angle at this point should be 50 to 55
degrees.
NOTE: If limit switch settings need to be changed, you will
need to recheck that the 500 lb. light comes on at 50
degrees to 55 degrees when lifting down.
7. Raise, extend, retract, and lower upper boom.
Check for smooth operation.
Upper Boom Length Switch (800 A only)
1. Lift upper boom to approximately horizontal.
2. Telescope boom out until 500 lb. light comes on
(may need to use auxiliary power to position boom
correctly).
3. Mark the wear pad location on the main fly boom.
4. Telescope the upper boom to full extension.
5. Measure from the mark on the fly boom to the wear
pad. The dimension should be 167" to 169".
6. Lower the tower boom until limit switch resets. This
should be 2 to 7 degrees below where the switch
4.10 BOOM VALVE ADJUSTMENT
1. Adjust the screws so the plunger on the valves has
0.250 in. (6.35 mm) travel remaining when the lower
boom is fully raised and retracted.
2. After the valves are adjusted, adjust the proximity
switches to within 0.20 in. (5 mm) of their target. The
LED’s on the proximity switches will light when the
power is on and the switch is within 0.20 in. (5 mm)
of the target. There is a proximity switch to back up
both valves.