Instruction Manual

MS 231, MS 231 C, MS 251, MS 251 C
English
47
Engine
STIHL single cylinder two-stroke engine
MS 231, MS 231 C
MS 251, MS 251 C
Ignition System
Electronic magneto ignition
Fuel System
All position diaphragm carburetor with
integral fuel pump
Chain Lubrication
Fully automatic, speed-controlled oil
pump with rotary piston
Weight
Cutting Attachment
Actual cutting length may be less than
the specified length
.325" Rollomatic E guide bars
3/8" P Rollomatic E guide bars
.325" chain
3/8" P chain
Chain sprocket
Noise and Vibration Data
For further details on compliance with
Vibration Directive 2002/44/EC see
www.stihl.com/vib.
Sound pressure level L
p
to ISO 22868
Specifications
Displacement: 42.6 cc
Bore: 42.5 mm
Stroke: 30 mm
Engine power to
ISO 7293:
2.0 kW (2.7 bhp)
at 10,000 rpm
Idle speed:
1)
2,800 rpm
Displacement: 45.6 cc
Bore: 44 mm
Stroke: 30 mm
Engine power to
ISO 7293:
2.2 kW (3.0 bhp)
at 10,000 rpm
Idle speed:
1)
1)
to ISO 11681 +/- 50 rpm
2,800 rpm
Spark plug (resistor
type):
NGK CMR6H,
BOSCH USR 4 A
C
Electrode gap: 0.5 mm
Fuel tank capacity: 390 cc (0.39 l)
Oil tank capacity: 200 cc (0.2 l)
dry, without bar and chain
MS 231: 4.8 kg
MS 231 C with ErgoStart and
quick chain tensioner: 5.1 kg
MS 251: 4.8 kg
MS 251 C with ErgoStart and
quick chain tensioner: 5.1 kg
Cutting lengths: 35, 40, 45 cm
Pitch: .325" (8.25 mm)
Groove width: 1.6 mm
Nose sprocket: 11-tooth
Cutting lengths: 30, 35, 40, 45 cm
Pitch: 3/8" P (9.32 mm)
Groove width: 1.3 mm
Nose sprocket: 9-tooth
Rapid Micro 3 (26 RM3) Type 3634
Rapid Duro 3 (26 RD3) Type 3667
Pitch: .325" (8.25 mm)
Drive link gauge: 1.6 mm
Picco Micro 3 (63 PM3) Type 3636
Picco Super 3 (63 PS3) Type 3616
Picco Duro 3 (63 PD3) Type 3612
Pitch: 3/8" P (9.32 mm)
Drive link gauge: 1.3 mm
7-tooth for .325"
Max. chain velocity to
ISO 11681: 25.6 m/s
Chain speed at maximum
power output: 19.3 m/s
6-tooth for 3/8" P
Max. chain velocity to
ISO 11681: 24.8 m/s
Chain speed at maximum
power output: 18.6 m/s
MS 231: 103 dB(A)
MS 231 C: 103 dB(A)
MS 251: 103 dB(A)
MS 251 C: 103 dB(A)