Installing the Threaded Fuel Filler Cap
WARNING
Unit vibrations can cause
an improperly tightened
fuel filler cap to loosen or
come off and spill quanti-
ties of fuel. To reduce the
risk of fuel spillage and
fire, tighten the fuel filler
cap by hand with as
much force as possible.
Damaged or Broken Cap
If your fuel cap does not tighten properly,
it may be damaged or broken. Stop
using the power tool and take it to your
authorized STIHL dealer for repair.
Vapor Lock
WARNING
Vapor lock occurs when fuel in the fuel
line or carburetor vaporizes, causing
bubbles to block the free flow of liquid
fuel into the carburetor. Vapor lock
cannot be relieved or affected by
opening the fuel tank. Removing the fuel
filler cap without first allowing the power
tool to cool adequately can result in fuel
spraying. Always follow the instructions
in this section when removing the fuel
cap.
BR 450, BR 450 C
To relieve vapor lock:
Place the Choke Knob in the cold
–
start position c and pull the starter
cord approximately 20 times to clear
the vapor and send liquid fuel into
the carburetor.
To start the power tool, move the
–
Choke Knob to the starting throttle
position o and pull the starter cord
approximately 10 times.
If your power tool will not restart, or
–
if vapor lock occurs again, the
power tool is being used in
conditions too extreme for the fuel
being used. Discontinue use and let
the engine cool completely before
attempting to start the power tool.
Before Operation
WARNING
Always check your power tool for proper
condition and operation before starting,
particularly the throttle trigger, setting
lever and stop switch. The throttle trigger
must move freely and always spring
back to the idle position. Never attempt
to modify the controls or safety devices.
WARNING
Check fuel system for leaks, especially
the visible parts, e.g., filler cap, hose
connections, manual fuel pump (only for
power tools equipped with a manual fuel
pump). Do not start the engine if there
are leaks or damage – risk of fire. Have
the power tool repaired by a STIHL
servicing dealer before using it.
WARNING
Never operate your power tool if it is
damaged, improperly adjusted or
maintained, or not completely and
securely assembled.
WARNING
Check that the spark plug boot is
securely mounted on the spark plug – a
loose boot may cause arcing that could
ignite combustible fumes and cause a
fire.
Keep the handles clean and dry at all
times; it is particularly important to keep
them free of moisture, pitch, oil, fuel mix,
grease or resin in order for you to
maintain a firm grip and properly control
your power tool.
WARNING
To reduce the risk of injury from parts
thrown by the fan wheel, check the fan
housing for damage (cracks or holes
that could allow foreign objects to
contact the fan wheel). If any such
damage is found, stop using the unit and
contact your STIHL dealer for repair.
WARNING
Adjust carrying harness to suit your size
before starting work.
In an emergency, you may slip out of the
harness and throw off the machine
quickly. Try slipping out of the harness a
number of times before using the
machine in order to become
accustomed to it. Do not throw off the
machine while practicing as it could
result in damage to the machine.
English
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