Husqvarna 326 E Workshop Manual page 33

3
Basic setting
The carburettor is set to its basic setting when test run at the
factory. The basic setting is "richer" than the optimal setting
(fast idle speed is 600–800 rpm under the recommended max.
speed) and should be kept during the engine's fi rst working
hours. Thereafter the carburettor should be fi ne tuned.
The default setting is:
H = 2 1/4 revolution open
L = 1 1/2 revolution open
The following conditions apply to all carburettor settings in
order to achieve the correct result:
• Defect-free spark plug with correct electrode gap.
• Defect-free air fi lter. Clean and correctly fi tted.
• There should be no leaks between the cylinder and the
distance piece and the carburettor and the distance piece.
Check the screws are tight.
• The fuel fi lter should be clean.
• The exhaust port (muffl er and cylinder) should not be com-
pletely or partially clogged.
• The cutting attachment (blade or trimmer head) must be fi t-
ted. The cord length must be as standard (cut by the cutter
on the splash guard).
• Correct fuel quality, minimum 89 octane.
With screwdriver 531 00 48-63 you can make small adjust-
ments of the jet screw needles without having to dismantle the
stop plugs.
With tool 504 62 29-01, the stop plugs are dismantled so that
the jet screw needles can be loosened for e.g. replacement or
cleaning.
Fine adjustment
Fine adjustment of the carburettor should be carried out after
the engine has been "run-in".
The engine must also be run warm for 4 to 5 minutes.
The carburettor setting must be carried out in two steps, and
in various ways depending on the type of cutting attachment
fi tted.
With a trimmer head
H-needle
Step 1: Twist the needle to the position where the engine is
almost running as a 4-stroke.
Step 2: With the engine turned off , then twist the needle a
third of a turn clockwise (leaner setting).
L-needle
Step 1: Twist the needle to the position providing maximum
engine speed.
Step 2: Then turn the needle anticlockwise so that the speed
drops by 500 rpm.
32
Fuel system
With blade or similar item
H-needle
Step 1: Twist the needle to the position that provides an engine
speed of 11,700 rpm.
Step 2: With the engine turned off , then twist the needle half a
turn clockwise (leaner setting).
L-needle
Step 1: Twist the needle to the position providing maximum
engine speed.
Step 2: Then twist the needle anticlockwise until the speed is
reduced by 500 rpm (richer setting).
NOTE!
Speed in excess of 11,700 rpm should be restricted
by the ignition system and not recorded by the
revolution counter.
After adjusting the settings, the locking plugs should be fi tted so
the jet needles cannot be turned anticlockwise.
Start the engine and check it responds quickly at full throttle,
the idle speed is 2,700 rpm and the fast idle speed is max
11,700 rpm.
NOTE!
If the cutting attachment rotates when the engine is
idling, the idle adjustment screw T should be turned
anticlockwise until the cutting attachment stops.