English
Releasing the chain brake
143BA012 KN |
NPull the hand guard back toward the front handle.
NOTICE
Always disengage chain brake before accelerating engine and before starting cutting work. The only exception to this rule is when you check operation of the chain brake.
High revs with the chain brake engaged (chain locked) will quickly damage the powerhead and chain drive (clutch, chain brake).
The chain brake is designed to be activated also by the inertia of the front hand guard
if the forces are sufficiently high. The hand guard is accelerated toward the bar nose - even if your left hand is not behind the hand guard, e.g. during a
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felling cut. The chain brake will operate only if it has been properly maintained and the hand guard has not been modified in any way.
Check operation of chain brake
Before starting work: Run engine at idle speed, engage the chain brake (push hand guard toward bar nose). Accelerate up to full throttle for no more than 3 seconds – the chain must not rotate. The hand guard must be free from dirt and move freely.
Chain brake maintenance
The chain brake is subject to normal wear. It is necessary to have it serviced and maintained regularly by trained personnel, such as your STIHL servicing dealer, at the following intervals:
every 3 | |
| months |
every 6 | |
| months |
Occasional usage: | every 12 |
| months |
Winter Operation
At temperatures below +50 °F (+10 °C)
NRemove the carburetor box cover
1 |
|
| KN |
2 | 137BA014 |
|
Nin the carburetor box cover, move the slide (1) from summer position to winter position (2)
Heated air is now drawn in from around the cylinder and mixed with cold air – this helps prevent carburetor icing.
NOTICE
Above +70 °F (+20 °C): Always return the cover to the position for "summer operation" again! Risk of engine malfunction – overheating!
NReplace the carburetor box cover and tighten the knob
Air filter system
NRetrofit new air filter if necessary – see "Air filter system"
MS 660
