Technical information

C
08.06 11
Introduction
CHAPTER
PAGEISSUE
TWO-STROKE ENGINE AM6
ENGLISH
SECTION 1
C - ENGINE
F. 5
F. 6
0,6 - 0,7 mm
Cs - Nm
20 - 25
1 Insulator
2 Body
3 Gasket
4 Electrode
5 Earth electrode
6 Threads
1.5 SPARK PLUGS
SPARK PLUG CHECK 1,000 km
• Remove the spark plug while the engine is hot ( taking utmost care to avoid scalding! ).
• The carbon deposits and the colour of the insulator ( around the central electrode ) provide good information as to
the heat range of the spark plug and to carburetion, lubrication and general condition of the engine.
•A light brown colour of the insulator indicates that engine working conditions are generally correct.
• Sooty black deposits, that are dry ( to the touch ) and opaque, are a sign that working temperature is too low,
i.e. that the heat range of the spark plug is too high, mixture too rich or ignition defective.
• A whitish colour of the insulator is indicative of too lean a mixture or of too low a heat range of the spark plug
(i.e. spark plug too “hot”).
• Check electrode gap (F.6) (even if the spark plug is new) by means of a calibrated thickness gauge. If necessary,
adjust by acting only on the earth electrode.