Stihl MS 661 C-M Instruction Manual

0458-759-8221-C
54
English 22 Inspection and Maintenance
22.2 Inspecting and Maintaining the Chain Saw
WARNING
To reduce the risk of personal injury from unintended
activation, shut off the engine and engage the chain brake
before inspecting the chain saw or carrying out any
maintenance, @ 8. Carry out only the maintenance
operations described in this manual. There are no user-
authorized repairs. STIHL recommends that repair work be
performed by authorized STIHL servicing dealers.
Proper maintenance of the chain saw includes the following
activities:
► Installing a new spark plug after approximately
100 operating hours or earlier if the electrodes are badly
eroded or corroded.
► Having the spark arresting screen inspected and cleaned
periodically by an authorized STIHL servicing dealer.
► Inspecting the chain sprocket periodically and having a
worn chain sprocket replaced by an authorized STIHL
servicing dealer.
► Inspecting the guide bar for proper groove depth and
spread and replacing the guide bar if it shows signs of
excessive wear or damage.
► Periodically sharpening the chain, maintaining the depth
limiting guides at the appropriate height and replacing the
saw chain when indicated by the relevant wear marks or
when the chain is damaged or shows signs of excessive
wear.
► Having worn, missing or damaged safety labels replaced
by an authorized STIHL servicing dealer.
If you make a warranty claim for a component that has not
been serviced or maintained properly, coverage may be
denied.
22.3 Inspecting and Maintaining the Chain Sprocket
► Shut off the engine and engage the chain brake.
► Remove the chain sprocket cover, saw chain and guide
bar.
► Check the chain sprocket cover for wear marks.
► If the wear marks are deeper than a = 0.020 in. (0.5 mm),
have the chain sprocket replaced.
STIHL recommends using genuine STIHL chain sprockets to
ensure optimal functioning of the chain brake.
Alternating between two chains helps reduce wear to the
chain sprocket.
22.4 Inspecting and Maintaining the Guide Bar
► Shut off the engine and engage the chain brake.
► Remove the guide bar and saw chain, @ 10.2.2.
► Measure the depth of the guide bar groove in the area with
the greatest wear using the measuring tool on the file
gauge (special accessory, not included).
► Replace the guide bar if the measured depth is less than
the required minimum depths stated in @ 24.4.
a
0000-GXX-2945-A0
a
0000-GXX-1217-A0

Stihl MS 661 C-M Specifications

General

Idle speed	- RPM
Motor type	2-stroke motor
Chain pitch	3/8 \
Blade length	800 mm
Product color	Black, Grey, Orange
Automatic oiling	Yes
Engine displacement	91.1 cm³
Power source	Gasoline
Sound power level	118 dB
Vibration emission	6.9 m/s²
Sound pressure level	105 dB

Weight and Dimensions

Weight	7400 g