User's Manual

MS 170, MS 170 C, MS 180, MS 180 C
English
40
Checking the Spark Plug
N Clean dirty spark plug.
N Check electrode gap (A) and
readjust if necessary – see
"Specifications".
N Use only resistor type spark plugs of
the approved range.
Rectify problems which have caused
fouling of spark plug:
– Too much oil in fuel mix.
– Dirty air filter.
– Unfavorable running conditions,
e.g. operating at part load.
Installing the spark plug
N Install the spark plug and connect
the spark plug boot (press it down
firmly) – reassembly all other parts
in the reverse sequence.
N Pull the starter rope only in the
direction specified
N Do not pull the rope over the edge of
the guide bush
N Do not pull out the rope more than
specified since it might break
N Do not let the starter grip snap back,
guide it slowly into the housing
See "Starting / stopping the engine"!
Replace a damaged starter rope in good
time or have it replaced by your dealer.
Replacing the starter rope and rewind
spring
N Remove the shroud – see "Shroud"
N Unscrew oil filler cap – drain oil tank
N Unscrew fuel tank filler cap – drain
fuel tank
Chain oil and fuel mixture must be
stored in canisters approved for this
purpose.
N Undo the screws on the fan housing
and hand guard respectively
N Remove the fan housing
N Tension or, if necessary, replace
the starter rope or rewind spring
000BA039 KN
A
Warning!
To reduce the risk of fire and burn injury,
use only spark plugs authorized by
STIHL. Always press spark plug boot (1)
snugly onto spark plug terminal (2) of
the proper size. (Note: If terminal has
detachable SAE adapter nut, it must be
attached.) A loose connection between
spark plug boot and ignition wire con-
nector in the boot may create arcing that
could ignite combustible fumes and
cause a fire.
1
2
000BA071 KN
Starter rope
To help prolong service life,
observe the following points: