Stihl HT 75 Manual De Instrucciones página 70

English
H
3 / 4
Turn high speed screw (H)
N
counterclockwise as far as stop (no
more than 3/4 turn).
Turn the low speed screw (L)
N
carefully clockwise as far as stop,
then turn it back 1 turn.
Start and warm up the engine.
N
Adjust idle speed with the idle speed
N
screw (LA) so that the chain does
not run.
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 or at sea level.
Rule of thumb:
Turn the high speed screw (H) about
one quarter turn for every 1000 m (3300
ft) change in altitude.
68
Conditions for adjustment
Carry out the standard setting.
N
Warm up the engine for
N
about 5 minutes.
L
1
Open the throttle wide.
N
At high altitude
Turn the high speed screw (H)
N
clockwise (leaner), no further than
stop, until there is no further
noticeable increase in engine
speed.
LA
At sea level
Turn the high speed screw (H)
N
counterclockwise (richer), no further
than stop, until there is no
noticeable increase in engine
speed.
It is possible that maximum engine
speed may be reached with the standard
setting in each case.
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 the engine for
N
about 5 minutes.
Engine stops while idling
Turn the idle speed screw (LA)
N
slowly clockwise until the engine
runs smoothly – the chain must not
rotate.
Chain rotates when engine is idling
Turn the idle speed screw (LA)
N
counterclockwise until the chain
stops moving and then rotate the
screw another 1/2 to 1 turn in the
same direction.
WARNING
If the chain continues moving when the
engine is idling, have your saw machine
and repaired by your servicing dealer.
Erratic idling behavior, engine stops
even though setting of LA-screw has
been corrected, poor acceleration
Idle setting is too lean
Idle setting is too lean: Rotate the
N
low speed screw (L) about 1/4 turn
counterclockwise until the engine
runs and accelerates smoothly.
Erratic idling behavior
Idle setting is too rich
Rotate the low speed screw (L)
N
about 1/4 turn clockwise until the
engine runs and accelerates
smoothly.
HT 75