Stihl FS 120 Service Manual

•
Now use the assembly drift (2)
1110 893 4700 to push the pis-
ton pin (1) out of the piston.
Note: If the piston pin is stuck, tap
the end of the drift lightly with a
hammer if necessary. Hold the
piston steady during this process
to ensure that no jolts are trans-
mitted to the connecting rod.

Remove piston and take the
needle cage out of the connect-
ing rod.
•
Inspect piston rings and replace
if necessary - see 4.6.
•
Thoroughly clean the gasket
seating surface (1).
•
Check that adapter sleeves (2)
are in place. Fit them if necess-
ary.
•
Lubricate the needle cage (3)
with oil and fit it in the connecting
rod.
•
To simplify assembly, heat the
piston and slip it over the con-
necting rod.
•
Installed position of piston:
1 = Marking
2 = Flywheel
•
Push the assembly drift, small
diameter first, through the piston
and small end (needle cage) and
line up the piston.
•
Fit the piston pin (1) on the
assembly drift (2) and slide it
into the piston (the pin slides
home easily if the piston is hot).
•
Modify sleeve of installing tool
5910 890 2210 as shown in
drawing.
a = 30 degrees
b = Ø 10 mm
250RA033
1 2
VA
250RA035
1 2
2
3
VA
250RA037
21
VA
250RA034
VA
250RA038
VA
250RA039
1 2
VA
250RA057
b
a
VA
4.5.2 Installation
)6)5 

Stihl FS 120 Specifications

General

Power source	Gasoline
Type	Brush cutter
Cordless	Yes
Head type	Nylon line
Handle type	U-type handle
Engine power	1.8 hp
Product color	Black, Metallic, Orange
Uncertainty K	2 m/s²
Sound power level	110 dB
Fuel tank capacity	0.64 L
Vibration emission	4.9 m/s²
Engine displacement	30.8 cm³
Sound pressure level	98 dB
Cutting diameter (max)	- mm

Weight and Dimensions

Length	1760 mm
Weight	6300 g