MS 441
English
40
N Pull off the spark plug boot (3).
N Unscrew the spark plug.
Checking the Spark Plug
N Clean dirty spark plug.
N Check electrode gap (A) and 
readjust if necessary ā see 
"Specifications".
N Use only resistor type spark plugs of 
the approved range.
Rectify problems which have caused 
fouling of spark plug:
ā Too much oil in fuel mix.
ā Dirty air filter.
ā Unfavorable running conditions, 
e.g. operating at part load.
Installing the spark plug
N Screw home the spark plug, fit the 
boot and press it down firmly.
N Fit the carburetor box cover.
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 (2) 
snugly onto spark plug 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 con-
nector in the boot may create arcing that 
could ignite combustible fumes and 
cause a fire.
00BA036 TR
1
219BA033 KN