
Note: Do not connect the tachometer directly to the
ignition system. The tachometer senses the magnetic
field from the ignition system.
Note: Do not remove the air filter cover.
WARNING: Adjust the idle speed outdoors. The
exhaust fumes are poisonous.
1. Operate the product for approximately 5 minutes
until it is warm.
2. Keep the instrument with the arrow down to the
position of the spark plug.
3. Adjust the idle screw to an idle speed of
approximately 2700 rpm.
If the cutting blade rotates at this speed, do a check of
the clutch.
6.7 Decompression valve
6.7.1 Decompression valve function
The decompression valve decreases the compression in
the cylinder when the engine starts. A small quantity of a
mixture of fuel and air goes through the decompression
valve (A). The valve closes because of the combustion
pressure when the engine fires (B).
A
B
6.7.2 To remove the decompression valve
•
Remove the decompression valve with a long socket
or the combination wrench.
6.7.3 To examine the decompression valve
1. Make sure that the decompression valve moves.
2. Clean the decompression valve.
3. Apply leakage spray or soap water on the
decompression valve before installation.
4. Install the decompression valve, refer to
the decompression valve on page 42.
1451 - 001 - 02.04.2020
Repair and servicing - 41