TEST REPORT Chainsaw Stihl MS 391

TEST REPORT
Chainsaw Stihl MS 391
Test no.: 5304
OWNER OF THE TEST CERTIFICATE:
Manufacturer and applicant:
Andreas Stihl AG & Co. KG
Badstrasse 115
D- 71336 Waiblingen
www.stihl.de

5303 - chainsaw STIHL MS 311
Test results and evaluations
Chainsaw STIHL MS 391
With up to 45 cm cutting length
Company: Andreas Stihl AG & Co. KG; Badstrasse 115; D- 71336 Waiblingen
Test item Test results Evaluation
Function
Chainsaw in the power class up to 4 kW, for semiprofessional
use
Engine power
P max = 3.3 kW
at Md max = 2.4 kW
Fuel consumption
Engine
speed
Torque
Spec. fuel
consumption
10000 min -1 3.2 Nm 52 kW/l
7000 min -1 max.3.5 Nm 41 kW/l
NE
max. power
max. torque
absolute / specific 1.8 l/h 421 g/kWh 1.4 l/h 431 g/kWh +
Exhaust emission
complies with level 2 of the standard 2002/88/EG Category SH:3 ≥ 50 cm³ engine
displacememt
EG-type approval by the federal transport agency e1*97/68SH3-IIA*2004/26*0555*00
Chain lubrication
Oil consumption at 5000 min -1 at 9000 min -1
min / max 4 ml/min 9 ml/min 7 ml/min 16 ml/min o
Sound pressure level
idling full load speed full throttle no load
speed
at ear of the operator 82 dB(A) 104 dB(A) 108 dB(A) --
Equivalent sound pressure level, total value 105 dB(A) (Average: idling – full load – full
throttle)
Accoustic power 115 dB(A) according to standard DIN EN ISO 22868
Vibration
++
Cutting equipment 40 cm 3/8 “ (chain
36 RMC)
idling
speed
full load speed
full throttle no load
front handle 3.0 m/s² 5.2 m/s² 4.2 m/s 2
rear handle 2.5 m/s² 5.3 m/s² 4.1 m/s²
Total equivalent vibration according to DIN EN ISO 22867
Front handle 4.2 m/s²; rear handle 4.1 m/s²
o
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5303 - chainsaw STIHL MS 311
Chain brake
Hand guard activation
Actuating
force
aver. braking time
max. braking
time
28 N 0.05 s 0.07 s
NE
Inertia activation
Kickback
horizontal acceleration
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vertical acceleration
346 m/s² 686 m/s²
Full chisel tooth 3/8“
Kickback angle with Chain stop angle
brake
Cutting equipment 40 cm 36 ° 26 ° NE
Weight
Weight per unit power
Operability / handling
With cutting
equipment, 45 cm
Without cutting
equipment
2.3 kg/kW 1.9 kg/kW
Control elements Easy to reach and use +
Primer
Deco-valve, Comfort models equipped with
"Ergostart" for easier start
Chain assembly Simple, chain sprocket easy accessed o
Chain tensioning simple, laterally in the chain sprocket cover o
Tank caps No tools required for removal, access good o
Maintenance
Air filter and spark plug covers and
casing
Air filter
Reliability
cleaning
soiling
One-piece, disassembly somewhat cumbersome,
requires tools (3 bolts)
No tools required, clamps
low
Initial tests revealed that the fuel tank could not be
emptied when the saw was mainly used for vertical
cuts. Furthermore the warm motor was sometimes
difficult to restart. Modified test models in which
these faults were corrected were tested at a later
stage. These modifications will be introduced as of
December 2011.
Operating manual clear, well illustrated +
Operator safety
EG-type examination test (DPLF) Test certificate no K-EG 2009/5143
GS-type examination test (DPLF) Test certificate no K-GS 2009/5142
Rating: ++ / + / o / - / --./.(o = Standard / NE= no evaluation, complies with tolerance value)
Tolerance values and evaluation criteria are described in the “Informationen zur
Gebrauchswertprüfung“(“Information about type examination tests”).
This publication is available from the DLG and the KWF.
o
+
-
+
+
o

5303 - chainsaw STIHL MS 311
Description and Technical Data
Engine
- Air-cooled single-cylinder two-stroke engine
- engine displacement 64.1 cm ³ ; bore 49 mm; stroke 34 mm
- Fuel: minimum octane number 90 ROZ; mixed lubrication 50:1
- Manufacturer's recommendation: Stihl MotoMix 92 ROZ
- Spark plug Bosch WSR-6F or NGK BPMR 7A
- Idling speed 2800 min -1 ; max. speed 13000 min -1 (electronic speed limiter)
Cutting equipment
- Clutch drum with external chain sprocket;
Guide bar with sprocket nose Rollomatic E
- Half or full chisel tooth, Pitch 3/8“, gauge 1.6 mm
- Guide bars for 37, 40 and 45 cm cutting lengths
Main dimensions and weights
Length incl. cutting equipment 45 cm 890 mm
engine unit without spiked bumper
445 mm
Width engine unit 195 mm
incl. handle
255 mm
Height engine unit 220 mm
with front hand guard
295 mm
Stump height chain sprocket cover 25 mm
handle
30 mm
Tank volume Fuel 600 ml
Chain oil
325 ml
Weight incl. cutting equipment 45 cm 7.7 kg
without cutting equipment
6.4 kg
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5303 - chainsaw STIHL MS 311
Test
Test carried out by
Kuratorium für Waldarbeit und Forsttechnik, Gross-Umstadt
DLG-Testzentrum Technik & Betriebsmittel, Gross-Umstadt
Field test
Forstliches Bildungszentrum Laubau
Forstliches Bildungszentrum Königsbronn
Authors
P. Müßig, KWF, Gross-Umstadt
J. Albert, DLG, Gross-Umstadt
FPA/DLG-Test committee
“Geräte und Werkzeuge“ (“Equipment and tools”)
Chairman: Sebastian Paar, FBZ Laubau
FPA / DLG-Approval until June 2016
In acknowledgment of the results of the test carried out by the KWF the approved
product is also entitled to carry the following test marks:
DLG-Testzentrum Technik & Betriebsmittel Groß-Umstadt
Max-Eyth-Weg 1 Telephone: 069/24788-611
D-64823 Gross-Umstadt Fax: 069/24788-110
Kuratorium für Waldarbeit und Forsttechnik e.V. (KWF)
Forsttechnischer Prüfungsausschuss (FPA)
E-mail: J.Albert@dlg.org
Internet: www.dlg-test.de
Spremberger Strasse 1 Telephone: 06078/785-0
D-64823 Gross-Umstadt Fax: 06078/785-50
E-mail: Muessig@kwf-online.de
Internet: www.kwf-online.de
ENTAM European Network for Testing of Agricultural Machines, is a cooperation
between European test stations. ENTAM aims to distribute test results for
agricultural and forestry equipment throughout Europe.
For more information about the network visit www.entam.com or contact ENTAM at the following e-mail address:
info@entam.com
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