Generac GN-320/360/410 Engine
— 10 —
Figure 9 — Removing Heat Shield
SERVICE AND ADJUSTMENTSENGINE SPEED
CAUTION: The engine speed was properly adjusted at the
factory and should require no additional adjustment. Do
not attempt to change engine speed. If you believe the
engine is running too fast or too slow, take your engine to
an authorized service center for repair and adjustment.
CHANGING THE ENGINE GOVERNED SPEED WILL
VOID THE ENGINE WARRANTY.
Your engine runs at a constant speed.This constant operating
speed is maintained by a mechanical, flyweight type, fixed
speed governor. DO NOT try to adjust the governed speed
setting for the following reasons:
• Operating the engine at high engine speeds is dangerous and
increases the risk of personal injury or damage to the
equipment.
• Operating the engine at low engine speeds with heavy loads may
shorten the engine’s life.
3. Set the spark plug gap (Figure 8) to 0.76mm (0.030 in.).
Install a correctly gapped spark plug into the cylinder head.
Figure 8 — Setting Spark Plug Gap
CLEANING THE SPARK ARRESTOR
SCREEN
The engine exhaust muffler has a spark arrestor screen. Inspect
and clean the screen every 100 hours of operation or once
each year, whichever comes first.
NOTE: If you use your engine on any forest-covered, brush-
covered or grass-covered unimproved land, it must
have a spark arrestor.The spark arrestor must be
maintained in good condition by the owner/operator.
Clean and inspect the spark arrestor screen as follows:
Inspect the screen and replace if it is torn, perforated or otherwise
damaged (see Steps 1-4 below). DO NOT USE a defective screen.If
the screen is not damaged, clean it with a commercial solvent.
If the spark arrestor is found to be damaged or defective, replace it
as follows:
1. Remove the four (4) screws that connect the heat shield to
the muffler (Figure 9).
2. Remove the four (4) screws that attach the spark arrestor
screen (Figure 9).
3. Replace damaged screen with new screen (Part No. 83083).
4. Reattach the screen and the heat shield with the four (4)
screws. Resintall the heat shield to the muffler with the four
(4) screws.
Spark
Arrestor
Screen
83083
Heat Shield
SET PLUG GAP AT0.76 mm
(0.030 inch)