Catalytic Converter; Checking The Spark Plug - Stihl BR 45 Instruction Manual

english / USA
Adjusting Idle Speed
L
Engine stops while idling
:
Open the low speed screw (L) one
full turn.
:
Turn idle speed screw (LA)
clockwise until the engine runs
smoothly – then turn it back about
1
/ turn from that position.
4
Erratic idling behavior, poor
acceleration
(although low speed screw is one full
turn open)
Idle setting too lean:
:
Turn low speed screw (L)
counterclockwise until the engine
runs and accelerates smoothly.
It is usually necessary to change the
setting of the idle speed screw (LA)
after every correction to the low speed
screw (L).
22

Catalytic Converter*

Units with a catalytic converter* may
only be operated with unleaded
gasoline and STIHL two cycle engine
oil or equivalent quality two cycle engine
oils in a mix ratio of 50:1 (see chapter
LA
"Fuel").
The catalylic converter in the muffler
reduces noxious emissions in the
exhaust gas.
Correct adjustment of the carburetor (if
adjustable) and observance of the
specified mix ratio of gasoline and two
cycle engine oil are essential to
minimize harmful exhaust emissions
and ensure a long catalyst service life.
* see "Guide to Using this Manual"

Checking the Spark Plug

Wrong fuel mix (too much engine oil in
the gasoline), a dirty air filter and
unfavorable running conditions (mostly
at part throttle etc.) affect the condition of
the spark plug. These factors cause
deposits to form on the insulator nose
which may result in trouble in operation.
BR 45