English
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.
24
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.
Installing the spark plug
N
Screw home the spark plug, fit the
boot and press it down firmly.
Lubricating the Gearbox
1
2
Check grease level regularly, about
every 25 hours of operation.
N
Unscrew the filler plug (1). If no
grease can be seen on the inside of
the filler plug, screw the tube (2) of
STIHL gear lubricant for
brushcutters – see "Special
Accessories" – into the filler hole.
N
Squeeze up to 0.2 oz (5 g) grease
into the gearbox.
Do not completely fill the gearbox
with grease.
N
Refit the filler plug and tighten it
down firmly.
2
1
FC 90