JLG 40H Service Manual User Manual
Page 53
SECTION 2 - PROCEDURES
3120240
– JLG Lift –
2-33
2.18 THROTTLE CHECKS AND
ADJUSTMENTS WISCONSIN ENGINE.
(SEE FIGURE 2-9.)
Checks.
1.
Check that carburetor throttle link is located at top of
governor arm.
2.
Check that spring is located at first or second spring
hole from top of governor arm. First hole is prefera-
ble. Second hole can be used when trying to stop
surging.
Adjustments.
1.
Disconnect the actuator rod from the arm. With the
aid of an assistant, start the engine from platform
and allow it to come up to operating temperature.
Adjust carburetor idle screw until engine runs at
1800 RPM. Shut down engine. Reattach actuator rod
to arm making sure that low engine setting remains
the same. If necessary, adjust slide pin to contact
low engine limit switch at 1800 RPM. Shut down
engine.
2.
With the aid of an assistant, start engine from plat-
form and allow to come up to operating tempera-
ture. Disconnect proportional dump valve wire.
Activate footswitch. Turn on HIGH ENGINE switch.
Hold drive controller in full drive position. Adjust
slide pin to contact high engine limit switch at 2400
RPM. Shut off all switches and controllers. Recon-
nect proportional dump valve wire.
NOTE: Early machines are at idle until a function is acti-
vated. Later machines are at idle only at platform
without footswitch activated. Therefore when setting
low engine speed on later machines it will not be
necessary to disconnect bang-bang dump valve wire
or operate a bang-bang function. Just activate foot-
switch to get low engine.
3.
If the engine hunts or surges in the maximum speed
no load condition, shut off engine. Disconnect car-
buretor throttle link from governor arm. Turn carbu-
retor throttle link (clockwise) one turn. Start engine
and activate HIGH ENGINE as in step 2. Be sure to
disconnect proportional dump valve wire.
4.
If surging continues, repeat step 3. Do not turn car-
buretor throttle link in any further than necessary or
governor performance will be affected.
5.
When surging is under control, check HIGH ENGINE
RPM. If necessary reset to 2400 RPM as in step 2.
Shut down engine.