Stihl MS 170 Instruction Manual page 8

English
Fuel
Your STIHL chain saw uses an oil-
gasoline mixture for fuel (see the
chapter on "Fuel" of your instruction
manual).
WARNING
Gasoline is an extremely
flammable fuel. If spilled
and ignited by a spark or
other ignition source, it
can cause fire and seri-
ous burn injury or
property damage. Use
extreme caution when
handling gasoline or fuel
mix. Do not smoke or
bring any fire or flame
near the fuel or the chain
saw. Note that combus-
tible fuel vapor may
escape from the fuel
system.
Fueling Instructions
WARNING
Fuel your chain saw in well-ventilated
areas, outdoors. Always shut off the
engine and allow it to cool before
refueling. Gasoline vapor pressure may
build up inside the fuel tank depending
on the fuel used, the weather conditions
and the tank venting system.
In order to reduce the risk of burns and
other personal injury from escaping gas
vapor and fumes, remove the fuel filler
cap on your chain saw carefully so as to
allow any pressure build-up in the tank
to release slowly.
6
Slowly turn the filler cap left to the vent
position of the cap at about 1/2 turn
where the cap is held in place by the
thread. Once the fumes have been
relieved, turn the cap further until the
cap can be removed from the tank
thread.
Never remove the fuel filler cap by
quickly turning it to the full open position
without letting it vent out any
vapor/pressure build-up at the
1/2 position.
Never remove the fuel filler cap while the
engine is running.
Select bare ground for fueling and move
at least 10 feet (3 m) from the fueling
spot before starting the engine. Wipe off
any spilled fuel before starting your
chain saw.
WARNING
Check for fuel leakage
while refueling and during
operation. If fuel leakage
is found, do not start or
run the engine until the
leak is fixed and any
spilled fuel has been
wiped away. Take care
not to get fuel on your
clothing. If this happens,
change your clothing
immediately.
Different models may be equipped with
different fuel caps.
Screw Cap
WARNING
Unit vibrations can cause
an improperly tightened
fuel filler cap to loosen or
come off and spill quanti-
ties of fuel. In order to
reduce the risk of fuel
spillage and fire, tighten
the fuel filler cap by hand
as securely as possible.
See also the "Fueling" chapter in your
Instruction Manual for additional
information.
Before Operation
Take off the chain guard (scabbard) and
inspect the chain saw for proper
condition and operation. (See the
maintenance chart near the end of the
instruction manual.)
WARNING
Always check your chain saw for proper
condition and operation before starting,
particularly the throttle trigger, throttle
trigger lockout, stop switch and cutting
attachment. The throttle trigger must
move freely and always spring back to
the idle position. The Master Control
Lever / stop switch must move easily to
STOP, 0 or †. 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
chain saws equipped with a manual fuel
pump). Do not start the engine if there
MS 170, MS 170 C, MS 180, MS 180 C