Engine Management; Adjusting The Carburetor - Stihl GS 461 Instruction Manual

Engine Management

Exhaust emissions are controlled by the
design of the engine and components
(e.g. carburation, ignition, timing and
valve or port timing).
GS 461

Adjusting the Carburetor

General Information
The carburetor comes from the factory
with a standard setting.
This setting provides an optimum fuel-air
mixture under most operating
conditions.
With this carburetor it is only possible to
correct the adjusting screws within fine
limits.
The ignition module limits maximum
engine speed. Therefore, maximum
engine speed cannot be increased by
turning the high speed screw (H) any
further clockwise (leaner).
Standard Setting
Shut off the engine.
N
Check the air filter and clean or
N
replace if necessary.
Check the spark arresting screen
N
(not in all models, country-specific)
in the muffler and clean or replace if
necessary.
Turn high speed screw (H)
N
counterclockwise as far as stop (no
more than 3/4 turn).
Turn the low speed screw (L)
N
clockwise as far as stop, then turn it
back 1/4 turn.
Adjusting Idle Speed
Before starting, open the shut-off cock
fully so that water flows to the diamond
abrasive chain – never allow chain to run
dry.
Carry out the standard setting.
N
Start and warm up the engine.
N
English
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