Generac Power Systems OHVI GSH 220 Service Manual page 24

SeCTIoN 5: oPTIoNAl Idle CoNTrol
Idle CoNTrol AdjuSTMeNT
GENERAL:
Idle speed will be correct when (a) the idle control solenoid is
positioned to maintain an idle speed equal to about 500-200
rpm (25-5 Hertz), and (b) when the carburetor idle speed stop
screw is set to maintain an idle speed of approximately 2280-
200 rpm (8-0 Hertz). Proper adjustment consists of first
positioning the idle control solenoid to obtain an idle speed
of 500-200 rpm. Fine adjustment can then be obtained by
setting the idle speed stop screw for an idle speed of 2280-
200 rpm (8-0 Hertz).
INITIAL ADJUSTMENT:
. Set the idle control switch to OFF.
2. Unplug all electrical loads from the generator.
. Connect an AC frequency meter into one of the generators
power receptacles.
. Crank and start the engine as outlined in the appropriate
owner's manual.
a. For units rated 60 Hertz, the frequency meter should read
about ,690-,80 rpm (high governed speed). This is
about 6.5-6.5 Hertz.
b. For units rated 50 Hertz, the meter should read ,00-
,090 rpm (50.5-5.5 Hertz).
5. Let the engine stabilize and warm up.
6. Set the idle control switch to ON. The idle control solenoid
should energize, and engine speed should decelerate to
idle speed.
7. If necessary, back the carburetor's idle speed stop screw
out so that governor lever travel is limited by the solenoid
and not by the idle stop screw.
a. Check the frequency meter reading.
b. Meter should indicate about ,500- 2,00 rpm (25-5
Hertz).
c. If reading is not within the stated range, adjustment of
the idle control solenoid is required.
8. To adjust the idle control solenoid, proceed as follows:
a. Loosen the solenoid JAM NUT, then turn the solenoid
BOLT clockwise (faster) or counterclockwise (slower).
b. When engine speed is 500- 200 rpm (25-5 Hertz), hold
that setting and tighten the solenoid JAM NUT.
c. When JAM NUT is tight, check that engine speed is still
,500- 2,00 rpm (25-5 Hertz).
FINAL ADJUSTMENT:
On the carburetor, turn the idle speed stop screw clockwise
(faster speed) until engine speed increases to 2,280-2,00 rpm
(8-0 Hertz) (see Figure 5-).
NOTE: Idle speeds less than about 38 Hertz could cause
the engine to stall when loads are suddenly applied.
JAM NUT
Figure 5-3. Initial Adjustment Points
Figure 5-4. Final Adjustment Point
5-2
BOLT
IDLE SPEED
STOP SCREW