Husqvarna 250 R 用户手册

下载
页码 48
English
 – 31
MAINTENANCE
Low speed jet L (240R, 240F, 250R, 252RX)
Try to find the highest idling speed, turning the low speed 
needle L clockwise respectively counter-clockwise. When the 
highest speed has been found, turn the low speed needle L 1/
4 turn counter-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 (240R, 240F)
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.
Apply full throttle and turn the high speed jet H very slowly 
clockwise until the engine slows down. Then turn the high 
speed jet H very slowly anticlockwise until the engine starts to 
run unevenly. Now turn the high speed jet H slowly clockwise 
a little way until the engine runs smoothly. 
Note that the engine should not be under load when you 
adjust the high speed jet H. You should therefore remove the 
cutting attachment, nut, support flange and drive disc before 
adjusting the high speed jet H.
The high speed jet H is adjusted correctly when the machine 
burbles a little. If the machine races then the setting is too 
lean. If the engine produces a lot of smoke and burbles a lot 
then the setting is too rich.
CAUTION!  For optimum adjustment of the carburettor, 
contact a qualified dealer/service workshop that has a 
revolution counter at their disposal. 
High speed jet H (250R, 252RX)
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.
250R, 252RX: 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
+ 1/4
H
H
H