7
SERVICE AND ADJUSTMENTS
ENGINE SPEED
The maximum engine speed was properly set
at the factory. Do not attempt to change this
setting. Operating the engine at high engine
speeds is dangerous and increases the risk of
personal injury or damage to the equipment.
If the engine is running too fast , take it to an
authorized service center for repair and adjust-
ment. CHANGING THE ENGINE’S MAXIMUM
GOVERNED SPEED WILL VOID THE ENGINE
WARRANTY.
Operating the engine at low engine speeds
with heavy loads may shorten the engine’s life.
Do not operate the engine below half throttle
except for idling.
The engine runs at a constant speed. This constant
operating speed is maintained by a mechanical, fly-
weight 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 dan-
gerous 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.
CARBURETOR ADJUSTMENTS
The carburetor of the engine is pre-set at the factory.
The carburetor should not be tampered with because
this will VOID THE EMISSION CONTROL SYSTEM
WARRANTY. If problems occur and the engine is
used at an altitude in excess of 5000 feet, contact the
nearest authorized dealer regarding high altitude set-
ting changes.
CHECKING/ADJUSTING VALVE TO ROCKER
ARM CLEARANCE
Without proper valve lash the engine may
require extreme force during starting. This can
be dangerous to the operator during manual
(pull) starts. Improper valve lash may also result
in premature wear of the engine.
After the first 50 hours of operation, remove the
rocker cover and check the valve to rocker arm clear-
ance.
When adjusting the clearance, the engine should be at
room temperature, and the piston should be at Top
Dead Center (TDC) of its compression stroke (both
valves are closed). The correct clearance is 0.05-
0.1mm (0.002-0.004 in.). Check and adjust the valve
to rocker arm clearance as follows:
1. Remove spark plug to avoid accidental starting.
2. Remove the four (4) screws from the rocker cover
(Figure 10).
3. Remove the rocker cover and rocker cover gas-
ket.
Figure 10 - Removing the Rocker Cover
4. Rotate the engine using the recoil until the engine
is at top dead center. This can be determined
by watching the piston movement through the
spark plug hole. Rotate the engine until the piston
reaches its highest point. Both valves should now
be fully extended.
5. Check the valve clearance before making any
adjustments.
6. If the clearance is incorrect, loosen the rocker
arm jam nut. Using an allen wrench to turn the
pivot ball stud, check the clearance between the
rocker arm and the valve stem with a flat feeler
gauge (Figure 11).
Figure 11 - Adjusting Valve to Rocker Arm
Clearance
Section 3 — Maintenance
GH - 410 Engine
To Next Page
Loading...
Need help?
General
