Engine Running Behavior; Lubricating The Gearbox - Stihl BT 121 Manual De Instrucciones

English / USA
To reduce the risk of fire and burn
injury, use only spark plugs
authorized by STIHL. Always press
spark plug boot (2) snugly onto
terminal (1) 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 connector in the boot
may create arcing that could ignite
combustible fumes and cause a fire.
22

Engine Running Behavior

If engine running behavior is
unsatisfactory even though the air filter
is clean and the carburetor properly
adjusted, the cause may be in the
muffler.
2
: Have the muffler checked for
contamination (coking).
STIHL recommends that all
maintenance and repair work be carried
out by an authorized STIHL dealer.
1

Lubricating the Gearbox

Check grease level after about every 50
hours of operation:
: Unscrew the filler plug (1). If no
grease can be seen on the inside of
the filler plug, refill the gearbox.
: Apply the tube (2) of STIHL gear
lubricant 0781 120 1117 to the filler
hole.
: Squeeze 1/4 oz (5 - 10g) grease into
the gearbox.
Do not not over-fill the gearbox.
: Refit the filler plug and tighten it
down firmly.
BT 121