Stihl MS 661 Instruction Manual

MS 661
English
45
Engine
STIHL single cylinder two-stroke engine
Ignition system
Electronic magneto ignition
Fuel system
All position diaphragm carburettor with
integral fuel pump
Chain lubrication
Fully automatic, speed-controlled oil
pump with reciprocating piston -
additional manual oil flow control
Weight
Cutting attachment
Rollomatic E guide bars
Rollomatic ES guide bars
Rollomatic ES Light guide bars
Saw chains 3/8"
Chain sprocket
The average chain speed during
operation is normally approx. 20% less
than the maximum chain speed to
ISO 11681. Contact the STIHL dealer
when selecting the personal protective
equipment.
Sound and vibration levels
For further details concerning
compliance with the Physical Agents
Directive Vibration 2002/44/EC, see
www.stihl.com/vib/
Sound pressure level L
peq
to ISO 22868
Sound power level L
w
to ISO 22868
Vibration level a
hv,eq
to ISO 22867
The K-factor in accordance with
Directive 2006/42/EC is 2.5 dB(A) for
the sound pressure level and sound
Specifications
Displacement: 91.1 cm
3
Cylinder bore: 56 mm
Piston stroke: 37 mm
Engine power
according to
ISO 7293:
5.4 kW (7.3 HP)
at 9500 rpm
Idle speed:
1)
1)
according to ISO 11681 +/- 50 rpm
2800 rpm
Spark plug
(suppressed):
Bosch WSR 6 F,
NGK BPMR 7 A
Electrode gap: 0.5 mm
Fuel tank capacity: 850 cm
3
(0.85 l)
Oil tank capacity: 400 cm
3
(0.4 l)
Dry, without cutting attachment
MS 661: 7.4 kg
Cutting lengths: 40, 45, 50, 63 cm
Pitch: 3/8"
Groove width: 1.6 mm
Sprocket nose: 10-tooth with cutting
lengths 40, 45,
50 cm
11-tooth with cutting
lengths 40, 45, 50,
63 cm
Cutting lengths: 40, 45, 50, 55, 71,
75, 80, 90 cm
Pitch: 3/8"
Groove width: 1.6 mm
Sprocket nose: 11-tooth
Cutting lengths: 71, 80, 90 cm
Pitch: 3/8"
Groove width: 1.6 mm
Sprocket nose: 11-tooth
Rapid Micro (36 RM) Type 3652
Rapid Super (36 RS) Type 3621
Rapid Super 3 (36 RS3) Type 3626
Pitch: 3/8" (9.32 mm)
Drive link gauge: 1.6 mm
7-tooth for 3/8" (rim sprocket)
Max. chain speed to
ISO 11681: 27.5 m/s
105 dB(A)
118 dB(A)
Left handle: 5.5 m/s
2
Right handle: 5.5 m/s
2

Stihl MS 661 Specifications

General

Displacement	91.1 cc
Chain Pitch	3/8"
Engine Power	5.4 kW
Fuel Capacity	825 ml
Chain Oil Capacity	360 ml
Guide Bar Lengths	90 cm