JLG 40H Service Manual - Manual (Page 41)

SECTION 2 - PROCEDURES
3120240 – JLG Lift –
2-21
7. With the aid of a assistant, start engine from basket
and allow to come to operating temperature. Dis-
connect bang-bang dump valve wire. Activate foot-
switch. Operate a bang-bang function switch to
increase RPM to low engine. Using a small screw-
driver set low engine at 1800 RPM at the Addco
electronic module. 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.
2.15 THROTTLE CHECKS AND PRECISION
GOVERNOR ADJUSTMENTS, ADDCO
(SEE FIGURE 2-6.)
NOTE: Never run fuel tank dry. Diesel engines cannot be
restarted after running out of fuel until fuel system
has been air-vented or ‘bled’ of air. See Deutz
Instruction Manual for procedure.
Checks.
1. Check that anti-dieseling solenoid is operating. If
solenoid is operating, an audible click at the carbu-
retor should be heard when ignition is switched on.
2. Check throttle linkage for smooth operation by rotat-
ing throttle lever by hand to full throttle position then
slowly back to idle position feeling closely for stick-
ing or binding. To accomplish this the throttle rod
must first be disconnected.
Choke Adjustments.
NOTE: Automatic choke and vacuum pulloff adjustment pro-
cedure to be made only on a cold engine.
1. Make sure choke body and mounting bracket are
positioned so that choke rod moves freely with no
binding anywhere through its stroke.
2. The choke spring should hold the choke plate firmly
closed but require only slight finger pressure to
open at 70 degrees F. (21.28 degrees C.)
3. Retract pulloff shaft until it bottoms (as if under
engine vacuum). Bend pulloff rod until a 3/8"
(9.53mm) rod just fits between choke plate and car-
buretor body.
4. The above procedure outlines the correct choke
system adjustment for most conditions. Some envi-
ronments such as high altitude, very warm or very
cold temperatures may require that the choke cover
be set richer or leaner, or the amount of putoff may
need to be varied somewhat.
Figure 2-5. Addco Adjustment, Ford.