MAINTENANCE
CarburetorBasic (factory) settings
The carburetor has been carefully preset at the fac-The carburettor is preset to the basic settings when
tory. However, additional adjustment may be requiredthe blower is tested at the factory. These basic
due to climate, altitude, gasoline and type of two-settings are the following:
stroke engine oil used. The instructions below
describe how carburetor adjustment should beTurn the H jet screw CCW against its stop.
carried out.Turn the L jet screw CCW against its stop.
The carburetor governs the engine speed via theThe recommended idling speed is 3,000 rpm.
throttle. Air and fuel are mixed in the carburetor. The
air/fuel mixture is adjustable. To utilize the blowerOs
maximum output, the settings must be correct.
Adjustment
The carburetor has three means of adjustment:To adjust the low speed jet (L)
1. Check that tube (15) and nozzle (14) are
H = High speed jetmounted on the blower.
L =Low speed jet2. Turn the H and L jet screws all the way CCW
T =Adjustment screw for idling
against the stop.
3. Start the blower as described on page 13 and
alternate letting it run at idling speed and at half
H L Tthrottle for 1 � 2 minutes to warm up. If the
engine will not run at idling speed, turn the T
screw CW until it does.
4. Turn the T jet screw until the engine runs
precisely at idling speed without dying.
5. Make a fine adjustment, turning the L screw to
let the engine run at max. idling speed. Then
turn the L screw max. 1/4 of a turn CCW.
6. Turn the T screw to increase the engine speed,
if necessary.
NOTE !
When setting the H jet, do not let the
engine run at full throttle for more than 10
seconds at a time. Alternate by letting the
engine run at idling speed for at least 10
seconds before giving it full throttle again.
To adjust the high speed jet, H
1. Start the blower as described on page 13 and
Functionalternate letting it run at idling speed and at half
throttle for 1 � 2 minutes to warm up.
The fuel quantity required in relation to the air flow,
2. Give the engine full throttle and adjust the H jet
provided by the opening in the throttle, is adjustedscrew until the engine runs at max. speed.
by the L and H jets. If they are screwed clockwise,
the air/fuel mixture becomes leaner (less fuel) and if3. Turn the H jet screw 1/8 of a turn counter-
clockwise (less than 1/8 of a turn if a stop
they are screwed counterclockwise, the mixture
becomes richer (more fuel). A leaner mixture givesrestricts this adjustment).
rise to a higher engine speed and a richer mixture
gives rise to a lower engine speed.
The T screw regulates the idling speed. Turning the
T screw clockwise will increase the idling speed;
turning it counterclockwise will lower the idling
speed.
20 � English |