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5
MS 311, MS 391
2.
Specifications
2.1
Engine
MS 311
MS 391
Displacement:
59 cm
3
64.1 cm
3
Bore:
47 mm
49 mm
Stroke:
34 mm
34 mm
Engine power to ISO 7293:
3 kW (4 bhp)
at 9,500 rpm
3.2 kW (4.4 bhp)
at 9,500 rpm
Maximum permissible engine speed
with guide bar and chain:
13,000 rpm
13,000 rpm
Idle speed:
2,800 rpm
2,800 rpm
Clutch:
Centrifugal clutch without
linings
Centrifugal clutch without
linings
Clutch engages at:
3,500 rpm
3,500 rpm
Engine housing leakage test
at gauge pressure:
0.5 bar
under vacuum:
0.5 bar
2.2
Fuel System
Carburetor leakage test at
gauge pressure:
0.8 bar
Operation of tank vent at
gauge pressure:
0.5 bar
Fuel:
as specified in instruction
manual
2.3
Ignition System
Air gap between ignition
module and fanwheel:
0.20...0.30 mm
Spark plug (resistor type):
NGK BPMR 7 A
BOSCH WSR6F
Electrode gap:
0.5 mm
2.4
Chain Lubrication
Speed-controlled oil pump with reciprocating piston and
manual flow control
Oil delivery rate:
Ematic oil pump
11.5 (+2.5) cm
3
/min
at 10,000 rpm
Oil delivery rate:
Adjustable oil pump
6.0 (+/-2.0)...17.5 (+3.0 / -4.5)
cm
3
/min at 10,000 rpm