Stihl 088 Owner's Manual page 50

10.2.3 Adjustment
Standard setting
If the carburetor has to be adjusted
from scratch, first carry out the
standard setting.
- Carefully screw down both adjusting
screws until they are hard against
their seats.
Then make the following adjustments:
H = Open high speed screw (1) 1 full
turn
L = Open low speed screw (2) 1 full
turn
A slight correction may be necessary if
the saw is used at high altitudes
(mountains) or at sea level.
For corrections to high speed
screw (H):
Use a tachometer - do not
exceed max. permissible
engine speed.
Engine can be damaged by lack of
lubricant and overheating.
Maximum engine speed with bar and
properly tensioned chain: 12,000 rpm
Note: If no tachometer is available, do
not turn the high speed or low speed
screws beyond the standard setting to
make the mixture leaner.
STIHL 088
• Check chain tension.
• Check air filter and clean if
necessary.
• Adjust idle speed correctly
(chain must not rotate).
• Start the saw - warm up the
engine.
Turn high speed screw (H) and low
speed screw (L) clockwise for leaner
mixture at high altitudes or
counterclockwise for richer mixture at
sea level.
Turn screws very slowly and carefully -
even slight adjustments produce a
noticeable change in engine running
behavior.
Note the following when making
corrections to high speed screw:
The setting of the high speed screw
(H) affects the maximum off-load
engine speed. If the setting is too lean,
the maximum permissible engine
speed will be exceeded and increase
the risk of engine damage.
Adjusting idle speed
A correction at the low speed screw
(L) usually necessitates a change in
the setting of the idle speed screw
(LA).
Engine stops while idling –
Check standard setting
Turn idle speed stop screw (LA)
clockwise until the chain begins to run
- then turn it back one quarter turn.
Chain runs while engine is
idling - Check standard setting
Turn the idle speed stop screw (LA)
counterclockwise until the chain stops
running - and then turn it about
another quarter turn in the same
direction.
Erratic idling behavior, poor
acceleration
Idle setting too lean. Turn the low
speed screw (L) counterclockwise
until the engine runs and accelerates
smoothly.
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