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22
English
SP 81
Standard Setting
:
Shut off the engine.
:
Check the air filter and clean or
replace if necessary.
:
Check the spark arresting screen* in
the muffler and clean or replace if
necessary.
:
Check adjustment of the throttle
cable and readjust if necessary –
see “Adjusting the Throttle Cable”.
:
Turn the high speed screw (
H
)
counterclockwise as far as stop (no
more than 3/4 turn).
:
Carefully screw the low speed
screw (
L
) down onto its seat
(clockwise) and then open it one full
turn counterclockwise.
:
Start the engine and allow it to warm
up.
Adjust engine idle speed with the
the idle speed screw (
LA
) so that
the rakes do not run.
*
see “Guide to Using this Manual”
Fine Tuning
A slight correction of the setting of the
high speed screw (
H
) may be necessary
if engine power is not satisfactory when
operating at high altitude.
Rule of thumb
Turn the high speed screw (
H
)
about 1/4 turn for every 1000 meter
(3300 ft) change in altitude.
Conditions for adjustment
:
Carry out standard setting.
:
Warm up engine for about
5 minutes.
:
Open the throttle wide.
:
At high altitude
:
Turn the high speed screw (
H
)
clockwise
(leaner), no further than
stop, until there is no noticeable
increase in engine speed.
It is possible that maximum engine
speed will be reached with the
standard setting.
Adjusting Idle Speed
It is usually necessary to change the
setting of the idle speed screw (
LA
)
after every correction to the low speed
screw
(
L
).
:
Warm up engine for about
5 minutes.
Engine stops while idling
:
Turn idle speed screw (
LA
) slowly
clockwise until the engine runs
smoothly – the rakes must not
move.
Rakes move when engine is idling
:
Turn the idle speed screw (
LA
)
slowly counterclockwise until the
rakes stop moving – then turn the
screw another 1/2 to 1 turn in the
same direction.