Stihl FS 550 User Manual

31FS 500, FS 550
English / USA
Cutting tool rotates when engine is
idling
: Turn idle speed screw (LA) slowly
counterclockwise until cutting tool
stops rotating and then turn the
screw about another quarter turn in
the same direction.
Erratic idling behavior, engine stops
even though setting of LA screw is
correct, poor acceleration
Idle setting too lean:
: Turn low speed screw (L)
counterclockwise (about
1
/
4
turn)
until the engine runs and
accelerates smoothly.
Erratic idling behavior
Idle setting too rich:
: Turn low speed screw (L) clockwise
(about
1
/
4
turn) until the engine runs
and accelerates smoothly.
If the engine is low on power, check the
spark arresting screen in the muffler.
: Release screw.
Pull off the spark plug boot.
: Remove mounting screws from
shroud (1) and lift shroud away.
: Take out the self-tapping
screws (2).
: Remove baffle (3) and spark
arresting screen (4).
* see "Guide to Using this Manual"
: Clean spark arresting screen if
necessary.
: If screen is damaged or coked up, fit
a new one.
: Assemble in the reverse sequence.
Spark Arresting Screen*
in Muffler
4
3
2
2
398BA034 KN
1

Stihl FS 550 Specifications

General

Engine Power	2.8 kW
Engine Type	2-stroke
Ignition System	Electronic
Fuel Capacity	0.99 liters
Fuel Tank Capacity	0.99 liters
Recommended Cutting Attachment	Metal Grass Cutting Blade
Starter	Recoil