
26
3
Fuel system
Carburettor adjustment under engine load
When adjusting a carburettor fitted with carburettor needles with plastic sleeves
with movement limiters, also called caps, both the carburettor needles H and L can
only be adjusted within very tight limits to satisfy, among others, the stringent
demands regarding the amount of hydrocarbons and nitrogen oxides in the exhaust
fumes.
To carry out adjustment when replacing needles or the entire carburettor the engine
must be under load. This is achieved by fitting a Trimmy Fix with the specified
length and diameter of trimmer cord. Consequently, the stated speed will be much
lower than with “normal” carburettor adjustment when the engine may run freely.
After replacing the needles or the entire carburettor, adjustment must be carried out
according to the instructions below.
The combiguard or trim guard must be fitted when adjusting the H-needle.
Adjusting the L-needle
1. Mount the Trimmy Fix (4 wires) and use 3.3 mm smooth
cord. The cord length should be 150 mm measured from the
end of the cord to the cord bushing on the trimmer head.
2. Run the engine warm for about 5 minutes. Let the engine
idle.
3. Turn the L-needle so that the highest speed is attained.
4. If the speed exceeds 3,700 rpm, reduce it with the aid of the
idling speed’s T-screw (T) and a carry out a new adjustment
in accordance with point 3.
5. Then turn the L-needle anticlockwise so that the speed drops
by 300 rpm.
6. Then adjust the idling speed to 2,800 rpm by turning the T-
screw.
7. When mounting the plastic sleeve on the L-needle, the
needle is turned a quarter-turn anticlockwise once the
optimal setting has been made and the plastic sleeve is
mounted so that the needle cannot be turned anticlockwise.
Then turn the L-needle back a quarter-turn.
IAdjusting the H-needle
1. Mount the Trimmy Fix (4 wires) and use 3.3 mm smooth
cord. The cord length should be 150 mm measured from
the end of the cord to the cord bushing on the trimmer
head.
2. Run the engine warm for about 5 minutes.
3. Adjust the H-needle so that the speed 8400 ± 200 rpm is
set.
4. Fit the plastic sleeve on the H-needle so that the needle
cannot be turned anti-clockwise.
Содержание 326C, 326L, 326LX-Series, 326LDX-Series
Страница 1: ...Workshop manual 326R 326L 326C English ...
Страница 31: ...30 4 Centrifugal clutch ...
Страница 35: ...34 5 Angle gear ...
Страница 45: ...44 6 Cylinder and piston ...
Страница 51: ...50 7 Crankshaft and crankcase ...
Страница 55: ...2004W38 114 03 03 26 ...