Oilguard - Dry Cut - Husqvarna K770 Workshop Manual

6.18.3 To assemble the throttle trigger and
throttle lock
1. Install the throttle trigger from the carburetor
compartment. Make sure that the spring comes out
through the handle.
2. Push in the spindle from the left side.
3. Push the throttle lock onto the shaft. Push the
throttle lock into position.

6.19 OilGuard - Dry Cut

6.19.1 Function
The OilGuard prevents the product from running with
incorrect fuel. For the OilGuard to operate, an oil
containing dye, "Husqvarna OilGuard oil", must be
added. Fuel analysis starts 10 seconds after startup and
continues for 50 seconds. If the OilGuard identifies
incorrect fuel, the engine speed limit is 3800 rpm.
A winding in the ignition module (1) gives electric current
to the OilGuard. The analysis unit has a light-emitting
diode (2). The light hits a light sensitive phototransistor
(3). The fuel flows between the diode and the
phototransistor. The OilGuard oil contains a yellow dye
which absorbs the light from the light-emitting diode. In
this mode, the product is operating as usual. If the
product is filled with clean gasoline or a different type of
701 - 002 -
1
2
oil, the light goes through the fuel. The light hits the
phototransistor and an electronic switch (4) engages
and sets the engine speed limit to 3800 rpm.
2
3
4
1
The blue plug above the stop button closes the circuit to
OilGuard. To override the OilGuard function, remove the
blue plug with a screwdriver and replace it with an
orange plastic plug.
1
5
1
2
2
Repair and servicing - 73