Engine Running Behavior; Lubricating The Gearbox - Stihl FS 90 Instruction Manual

English
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
securely attached.) A loose connection
between spark plug boot and ignition
wire connector in the boot may create
arcing that could ignite combustible
fumes and cause a fire.
Installing the spark plug
Screw home the spark plug, fit the
N
boot and press it down firmly.
38

Engine Running Behavior

If engine running behavior is
unsatisfactory even though the air filter
1
is clean and the carburetor is properly
adjusted, the cause may be the muffler.
Have the muffler checked for
contamination (carbonization) by your
servicing dealer.
STIHL recommends that you have
2
servicing and repair work carried out
exclusively by an authorized STIHL
servicing dealer.

Lubricating the Gearbox

1
2
Check the grease level regularly –
N
about every 25 hours of operation.
Unscrew the filler plug (1). If no
N
grease can be seen on the inside of
the filler plug, screw the tube (2) of
STIHL gear lubricant (special
accessory) into the filler hole.
Squeeze up to 5 g (1/5 oz) grease
N
into the gearbox.
NOTICE
Do not completely fill the gearbox with
grease.
Remove the tube of grease (2).
N
Refit the filler plug and tighten it
N
down firmly.
FS 90, FS 90 R