Stihl FS 91 R User Manual

FS 91, FS 91 R
English
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WARNING
To reduce the risk of fire and burn injury,
use only spark plugs authorized by
STIHL. Always press the spark plug
boot (1) snugly onto the spark plug
terminal (2).
Do not use a spark plug with a
detachable SAE adapter terminal (3).
Arcing may occur that could ignite
combustible fumes and cause a fire.
This can result in serious injuries or
damage to property.
N Only use resistor type spark plugs
with solid, non-threaded terminals
Installing the Spark Plug
N Screw the spark plug (3) into the
cylinder.
N Tighten down the spark plug (3) with
the combination wrench.
N Press the boot (2) firmly onto the
spark plug.
N Fit the cover (1) and screw it down
firmly.
If engine running behavior is
unsatisfactory even though the air filter
is clean and the carburetor is properly
adjusted, the cause may be the muffler.
Have the muffler checked for
contamination (carbonization) by your
servicing dealer.
STIHL recommends that you have
servicing and repair work carried out
exclusively by an authorized STIHL
servicing dealer.
2
1
0000-GXX-1831-A0
3
Engine Running Behavior

Stihl FS 91 R Specifications

General

Type	String trimmer
Cordless	Yes
Head type	Nylon line
Handle type	D-loop handle
Engine power	1.3 hp
Product color	Black, Metallic, Orange
Uncertainty K	2 m/s²
Rotational speed	8000 RPM
Number of strokes	4
Sound power level	107 dB
Fuel tank capacity	0.71 L
Vibration emission	3.7 m/s²
Engine displacement	28.4 cm³
Sound pressure level	96 dB
Cutting diameter (max)	- mm
Power source	Gasoline

Weight and Dimensions

Length	1800 mm
Weight	5500 g