Zenoah GZ381 Manual De Usuario página 21

The brake is engaged when the front hand guard (B) is
pushed forwards.
(Fig. 19)
This movement activates a spring-loaded mechanism
that tightens the brake band (C) around the engine drive
system (D) (clutch drum).
(Fig. 20)
The front hand guard is not designed solely to activate
the chain brake. Another important feature is that it
reduces the risk of your left hand hitting the chain if you
lose grip of the front handle.
The chain brake must be engaged before starting the
chainsaw to prevent the saw chain from rotating.
(Fig. 21)
Use the chain brake as a "parking brake" when starting
and when moving over short distances, to reduce the
risk of moving chain accidentally hitting your leg or
anyone or anything close by.
To release the chain brake pull the front hand guard
backwards, towards the front handle.
(Fig. 22)
Kickback can be very sudden and violent. Most
kickbacks are minor and do not always activate the
chain brake. If this happens you should hold the chain
saw firmly and not let go.
(Fig. 23)
The way the chain brake is activated, either manually or
automatically by the inertia release mechanism,
depends on the force of the kickback and the position of
the chain saw in relation to the object that the kickback
zone of the bar strikes. If you get a violent kickback
while the kickback zone of the bar is farthest away from
you the chain brake is designed to be activated by the
inertia in the kickback direction.
(Fig. 24)
If the kickback is less violent or the kickback zone of the
bar is closer to you the chain brake will be activated
manually by the movement of your left hand.
In the felling position the left hand is in a position that
makes manual activation of the chain brake impossible.
With this type of grip, that is when the left hand is placed
so that it cannot affect the movement of the front hand
guard, the chain brake can only be activated by the
inertia action.
(Fig. 25)
Common questions about kickback
• Will my hand always activate the chain brake
during a kickback?
No. It takes a certain force to move the hand guard
forward. If your hand only lightly touches the front
hand guard or slips over it, the force may not be
enough to trigger the chain brake. You should also
272 - 008 -
maintain a firm grip of the chainsaw handles while
working. If you do and experience a kickback, your
hand may never leave the front handle and will not
activate the chain brake, or the chain brake will only
activate after the chainsaw has swung around a
considerable distance. In such instances, the chain
brake might not have enough time to stop the saw
chain before it touches you. There are also certain
positions in which your hand cannot reach the front
hand guard to activate the chain brake; for example,
when the saw chain is held in felling position.
• Will my inertia activated chain brake always
activate during kickback in the event of a
kickback?
No. First, your brake must be in working order.
Testing the brake is simple, see instructions under
Examination, maintenance and service
the heading
of the product's safety equipment on page 31 . We
recommend you do this before you begin each work
session. Second, the kickback must be strong
enough to activate the chain brake. If the chain
brake is too sensitive it would activate all the time,
which would be a nuisance.
• Will my chain brake always protect me from
injury in the event of a kickback?
No. First, the chain brake must be in working order
to provide the intended protection. Second, it must
be activated during the kickback as described above
to stop the saw chain. Third, the chain brake may be
activated but if the guide bar is too close to you the
brake might not have enough time to slow down and
stop the saw chain before the chainsaw hits you.
WARNING: Only you and proper working
technique can eliminate kickback and its
dangers.
Throttle trigger lockout
The throttle trigger lockout prevents accidental operation
of the throttle trigger. If you put your hand around the
handle and press the throttle trigger lockout (A), it
releases the throttle trigger (B). If you release the
handle, the throttle trigger and the throttle trigger lockout
move back to their initial positions. This function locks
the throttle trigger at idle speed.
(Fig. 26)
Chain catcher
The chain catcher is designed to catch the chain if it
snaps or jumps off. This should not happen if the chain
is properly tensioned (see instructions under the
To tension the saw chain on page 34 ) and if
heading
the bar and chain are properly serviced and maintained
(see instructions under the heading
page 30 ).
(Fig. 27)
Maintenance on
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