Decompression Valve - Husqvarna K770 Workshop Manual

3. Adjust the idle screw to an idle speed of
approximately 2,700 rpm.
If the cutting blade rotates at this speed, the clutch or
the friction retarder must be examined.
6.6.20 To assemble the air valve
1. Attach the air valve to the carburetor with 2 screws.

6.7 Decompression valve

6.7.1 Function
The decompression valve decreases the compression in
the cylinder when the engine is started. A small quantity
of fuel/air mixture leaks out through the decompression
valve, as shown in fig. 1. When the engine fires the
40 - Repair and servicing
valve will close because of the combustion pressure, as
in fig. 2.
1
6.7.2 To disassemble the decompression valve
1. Remove the decompression valve with a long socket
or the combination wrench.
2
651 - 001 - 27.06.2018