Service And Adjustments; Throttle Linkage Adjustment; Adjusting The Carburetor; Adjusting Valve Clearance - Generac Power Systems NP-30G Series Owner's Manual And Installation Instructions

DANGER: DO NOT USE ANY JUMPER CABLES
OR BOOSTER BATIERY TO CRANK AND START
THE GENERATOR ENGINE. IF ANY BATIERY HAS
DISCHARGED, REMOVE IT FROM THE VEHICLE
FOR RECHARGING.
SERVICE AND ADJUSTMENTS
• ENGINE SPEED
Engine speed is completely computer-controlled.
There is no adjustment for speed on the unit. The
computer adjusts the engine speed using an electron-
ic governor throttle control. The computer monitors
the demand for power and adjusts the engine speed
accordingly. This allows the engine to produce only
the power required, resulting in fuel economy as well
as lowering the overall noise emitted.
NOTE: The computer will disable the electrical load
capabilities of the generator and enter a fault condi-
tion if you accelerate the throttle manually or any
other way.
THROTTLE LINKAGE ADJUSTMENT
If needed, you can adjust the length of the linkage rod
between the electronic governor lever arm and the
carburetor throttle lever arm. This adjustment helps to
establish the proper travel relationship between the
two lever arms. If this adjustment is not properly set,
the computer will NOT have control of the full range of
engine speed. If the rod adjustment is set too short,
the computer will not have access to wide open throt-
tle or "full power'' conditions. If the rod adjustment is
set too long, the computer will not have access to
closed throttle or "no power'' conditions.
Use the following procedure to assure the linkage rod
is properly adjusted:
1. Start the generator, then shut it down right away. As the
engine coasts to a stop, observe from above the engine
as the throttle lever on the carburetor rotates counter-
clockwise.
2. There should be a gap of 0.003 inch (0.08-0.5mm)
between stop tab on throttle lever arm and the stop block
on the carburetor die casting (Figure 8).
Figure 8 -
Gap
Betweern
Stop l"ao and Stop Bloc
I.Al
CAUTION: Do not overbend the spring clip or the
~
clip
will
lose its clamping force.
3. With pliers, lightly compress the spring clip on the carbu-
retor lever arm. This allows the linkage rod to slide freely
through the clip. While the clip is compressed, rotate the
throttle lever in the appropriate direction to increase or
decrease the gap until there is 0.003 inch (0.08-0.5mm)
clearance (Figure 9).
4. Release spring clip so you can secure adjustment. This
allows the carburetor and the electronic governor to be
synchronized.
ADJUSTING THE CARBURETOR
The carburetor of your generator is preset at the fac-
tory. The carburetor should not be tampered with, as
this will void the emission control system warranty. If
your generator is used at altitudes in excess of 5000
feet, consult your Generac Authorized Service Facility
regarding high altitude jetting changes.
ADJUSTING VALVE CLEARANCE
After the first 50 hours of operation, you should adjust
the valve clearance in the engine.
When adjusting valve clearance, the engine should
be at room temperature and the piston should be at
Top Dead Center (TDC) of its compression stroke
(both valves closed). Correct clearance is 0.001-
0.003 inch (0.03-0.0?mm). Adjust valve clearance as
follows:
1. Loosen the rocker arm jam nut. Use an allen wrench to
turn the pivot ball stud while checking clearance between
the rocker arm and the valve stem with a feeler gauge
(Figure 1 0 on page 12).
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