Carburettor without movement limiters, Fine adjustment

MAINTENANCE

Rec. idle speed: 2500 rpm
!	WARNING! Contact your servicing
!	dealer, if the idle speed setting cannot be
	adjusted so that the chain stops. Do not
	use the chain saw until it has been
	properly adjusted or repaired.

Fine adjustment

When the machine has been ”run-in” the carburettor should be ﬁnely adjusted. The ﬁne adjustment should be carried out by a qualiﬁed person. First adjust the L-jet, then the idling screw T and then the H-jet.

Changing the type of fuel

Fine tuning may be required if the chain saw, after changing the type of fuel, performs differently with regard to starting, acceleration, maximum speed, etc.

Conditions

•Before any adjustments are made the air ﬁlter should be clean and the cylinder cover ﬁtted. Adjusting the carburettor while a dirty air ﬁlter is in use will result in a leaner mixture next time the ﬁlter is cleaned. This can give rise to serious engine damage.

•Do not attempt to adjust the L and H jets beyond either stop as this could cause damage.

•Now start the machine according to the starting instructions and let it warm up for 10 minutes.

CAUTION! If the chain rotates while idling the T- screw must be turned anti-clockwise until the chain stops.

•Place the machine on a ﬂat surface so that the bar points away from you and so that the bar and chain do not come into contact with the surface or other objects.

Low speed jet L

Turn the low speed jet L clockwise until it stops. If the engine accelerates poorly or idles unevenly, turn the low speed jet L anticlockwise until good acceleration and idling are achieved.

CAUTION! If the chain rotates while idling the T-screw must be turned anti-clockwise until the chain stops.

Fine adjustment of the idle speed T

Adjust the idle speed with the T-screw. If it is necessary to re-adjust, turn the T-screw clockwise while the engine is running, until the chain starts to rotate. Then turn anti- clockwise until the chain stops. When the idle speed is correctly adjusted the engine should run smoothly in every position and the engine speed should be safely below the speed at which the chain starts to rotate.

WARNING! Contact your servicing

! dealer, if the idle speed setting cannot be adjusted so that the chain stops. Do not use the chain saw until it has been properly adjusted or repaired.

High speed jet H

At the factory the engine is adjusted at sea level. When working at a high altitude or in different weather conditions, temperatures and atmospheric humidity, it may be necessary to make minor adjustments to the high speed jet.

CAUTION! If the high speed jet is screwed in too far, it may damage the piston/cylinder.

When test run at the factory, the high speed jet is set so that the engine satisﬁes the applicable legal requirements at the same time as achieving maximum performance. The carburettor’s high speed jet is then locked using a limiter cap in the fully screwed out position. The limiter cap limits the potential to adjust the high speed jet to at most half a turn.

To adjust the carburettor correctly you should contact a mechanic with access to a rev counter.

Correctly adjusted carburettor

When the carburettor is correctly adjusted the machine accelerates without hesitation and 4-cycles a little at full throttle. It is also important that the chain does not rotate at idle. If the L-jet is set too lean it may cause starting difﬁculties and poor acceleration. If the H-jet is set too lean the machine will have less power, poor acceleration and could suffer damage to the engine.