Jonsered FC2145W - Manual (Page 30)

MAINTENANCE
30 – English
Low speed jet L
Try to find the highest idle speed by turning the low speed
jet L clockwise then anti-clockwise. When the highest
speed has been found, turn the low speed jet L 1/4 turn
anti-clockwise.
CAUTION! If the cutting attachment rotates when the
engine is idling the idle adjustment screw T should be
turned anti-clockwise until the cutting attachment stops.
Fine adjustment of the idle speed T
Adjust the idle speed using the idle adjustment screw T, if
it is necessary to readjust. First turn the idle adjustment
screw T clockwise until the cutting attachment starts to
rotate. Then turn the screw anticlockwise until the cutting
attachment stops. The idle speed is correctly adjusted
when the engine will run smoothly in every position. The
idle speed should also be well below the speed at which
the cutting attachment starts to rotate.
High speed jet H
The high speed jet H affects the engine power, speed,
temperature and fuel consumption. If the high speed jet H
is set too lean (screwed in too far) the engine speed will
be too high and cause engine damage. Do not let the
engine run at full speed for more than 10 seconds.
Setting procedure without a load (Blade can be used)
The machine is equipped with speed control in the ignition
system. It is extremely important to be aware of this when
adjusting the carburettor.
BC 2145, CC 2145: Speed control at: 12500 rpm
FC 2145, FC 2145 S, FC 2145 W: Speed control at:
13500 rpm
When attempting to adjust the speed over that specified,
the speed is not changed, but only causes the engine to
receive too little fuel resulting in a large risk of engine
failure.
Run the machine warm for approximately 5 minutes
alternating between short intervals of full throttle and
idling. When the carburettor is to be adjusted, apply full
throttle and turn the H-needle anti-clockwise until the
engine speed reaches 10,500-11,000 r/min (burbles) or
until the cap reaches its stop position. Now turn the H-
needle slowly clockwise until the engine reaches the
speed when the speed control comes into force. In some
cases, speed control can come into force at 200-300 revs
below or above that specified. It is important that you do
not continue to turn the H-needle clockwise when the
engine speed has stabilised. Screw the H-needle (anti-
clockwise) a few tenths of a turn instead.
Setting procedure with a load (Trimmer head should
be used)
Ensure the length of the trimmer cord is correct, i.e.
exactly reaches the knife on the trimmer guard. Use either
3 mm or 3.3 mm diameter trimmer cord.
Run the machine warm for about 5 minutes mostly at full
throttle. When the carburettor is to be adjusted, apply full
throttle and turn the H-needle anti-clockwise until the
engine burbles or until the cap reaches its stop position.
(If the engine runs smoothly when the cap is in its stop
position no further adjustment is necessary!) Turn the H-
needle slowly clockwise until the engine runs absolutely
smoothly. (Burbling has stopped completely). Now screw
the H-needle (anti-clockwise) a few tenths of a turn.
CAUTION! For optimum adjustment of the carburettor,
contact a qualified dealer/service workshop that has a
revolution counter at their disposal.
!
WARNING! If the idle speed cannot be
adjusted so that the cutting attachment
stops, contact your dealer/service
workshop. Do not use the machine until
it has been correctly adjusted or
repaired.
L H
L H
H
H