Partner K 650/700 Active Workshop Manual page 34

H
7/8
501 60 02-02 502 71 14-01
Fuel system
The adjustment of the carburettor may vary somewhat depending on the humidity,
temperature and air pressure.
L
L = Low speed nozzle
H = High speed nozzle
T = Adjuster screw for idling
● With the L and H nozzles the fuel volume is adjusted to the air flow which the
opening of the throttle control permits. If they are screwed clockwise the air/fuel
mixture becomes lean (less fuel) and if they are screwed anti-clockwise the air/
fuel mixture will become rich (more fuel).
A lean mixture gives higher revs and a rich mixture gives lower revs.
● The T-screw regulates the position of the throttle control during idling. If the T-
screw is screwed clockwise a higher idling speed will be obtained, and if it is
screwed anti-clockwise a lower idling speed will be obtained.
T
Basic setting (not EPA models)
The carburettor is given a basic setting when tested at the factory. This basic setting is
1 1/4
slightly "richer" than the optimum setting and should be maintained during the first few
hours the engine is used, after which it should be fine adjusted. The basic setting can
vary between:
H = 7/8 to 1 turn
L = 1 to 1 1/4 turn
The basic setting should be made when the engine is switched off.
Check that the air filters are clean.
Screw the nozzle needles (H) and (L) carefully to the bottom (clockwise).
Then unscrew them to the recommended basic setting.
Start the engine and run until warm, for about 5 minutes.
If the engine's idling speed is too high or too low adjust it with the idling adjuster screw
(T) until the cutting disc just stops/begins to rotate (approx. 2,500 rpm).
Check with tachometer 502 71 14-01.
Low speed nozzle (L) (not EPA models)
Run at full throttle a few times and check that the engine accelerates without delay. If
an adjustment is necessary try to achieve maximum idling speed by slowly turning the
low speed nozzle (L) clockwise until the engine hesitates from lack of fuel, and then
open the nozzle (anti-clockwise) 1/8 of a turn.
Check the acceleration of the engine.
NOTE!
If the low speed nozzle is set too lean (L-needle screwed in too far) this will result in
difficulty starting the engine. After a correct adjustment of the low speed nozzle (L) the
high speed nozzle (H) can be adjusted.
High speed nozzle (H) (not EPA models)
The engine has a carburettor with built-in speed limiter.
At maximum revs the engine receives an extra volume of fuel which prevents the engine
overspeeding. The speed limiter has a fixed setting and cannot be adjusted.
Screw in the H-needle to the limiting position where the engine begins to falter during
acceleration. Use short, rapid bursts from idling speed.
From this position the H-needle is then opened less than 1/8 of a turn (45°), which gives
the carburettor setting for maximum engine power.
Check with a tachometer that the engine does not overspeed the permissible maximum
speed (9,600 ± 400 rpm).
!
WARNING!
If the high speed nozzle is set too lean (screwed in too far clockwise) this will
reduce the power of the engine and can result in overheating and subsequent
damage to the engine.
The high speed nozzle (H) should be adjusted for maximum power and not
maximum speed.
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