Generac Power Systems 941-2 Service Manual page 65

ADJUSTMENT
The carburetor used on the GV-220 engine has a
FIXED, NON-ADJUSTABLE Low Speed Jet.
ENGINE SPEED
Engine speed is controlled by the A6060 circuit board.
That circuit board signals a stepper motor which
moves the throttle linkage. Engine speed will vary in
response to changes in generator AC output voltage.
The circuit board monitors the demand for power and
adjusts the engine speed accordingly. This permits
the engine to deliver only the power needed.
NOTE: Do NOT attempt to accelerate the engine
manually by, grasping the throttle or throttle link-
age. This win cause the system to enter a fault
condition and terminate generator AC output.
THROTTLE LINKAGE ADJUSTMENT
If necessary, the length of the linkage between the
stepper motor and the carburetor throttle lever arm
can be adjusted. This adjustment helps to establish
the proper travel relationship of the linkage. If the
adjustment is not correct, the A6060 board will not be
able to control the full range of engine speed. The fol-
lowing conditions might occur:
• If the throttle linkage is set too short, the system will
not be able to provide wide open throttle or full
power conditions.
• If the linkage is set too long, the system will not be
able to provide closed throttle or no power condi-
tions.
Use the following procedure to ensure the linkage rod
is properly adjusted:
1. Start the engine and immediately shut it down. As the engine
coasts to a stop, observe from above the engine as the carbu-
retor throttle lever rotates counterclockwise.
2. There should be a gap of about 0.003 inch (0.08-0.5mm)
between the stop tab on the throttle lever arm and the stop
block on the carburetor casting. See Figure 4.
CAUTION! The next step involves bending a
!
spring clip. Do NOT overbend the clip or it
may lose its clamping force.
3. Use pliers to lightly compress the spring clip on the carburetor
lever arm (Figure 5). This permits the linkage rod to slide freely
through the clip. With the clip compressed, rotate the throttle
lever in the appropriate direction until there is a 0.003 inch
(0.08-0.5mm) gap.
4. Release the spring clip to lock in the adjustment.
Figure 4. Set Gap Between Stop Tab and Stop Block
Figure 5. Adjusting Throttle Linkage
CARBURETOR REMOVAL
To remove the carburetor from the engine, proceed
as follows (see Figure 6, next page):
1. Disconnect the carburetor fuel inlet line.
2. Loosen the clamp and disconnect the carburetor air inlet hose.
3. Remove the two M6-1.00 x 90mm screws that retain the carbu-
retor.
4. Remove the carburetor air inlet adapter, the air inlet adapter
gasket, carburetor and carburetor to skirt gasket.
5. Remove the sheet metal carburetor skirt.
6. Remove two gaskets and the carburetor spacer.
Section 3.4
CARBURETOR
Page 3.4-3