KM 111 R, KM 131 R
English
19
N If the engine is down on power, 
check the spark arresting screen in 
the muffler.
N Wait for the muffler to cool down.
N Take out the screw (4).
N Lift the spark arresting screen (5) 
and pull it out.
N Clean the spark arresting 
screen (5). If the screen is damaged 
or heavily carbonized, install a new 
one.
N Refit the spark arresting screen (5).
N Insert the screw (4) and tighten it 
down firmly.
If there is a loss of engine power, the 
machine is difficult to start or runs poorly 
at idle, first check the spark plug.
Install a new spark plug after 
approximately 100 operating hours or 
earlier if the electrodes are 
eroded/corroded.
The 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 degrade performance.
Removing the Spark Plug
N Remove the cover (1).
N Pull off the spark plug boot (2).
N Unscrew the spark plug (3).
Checking the Spark Plug
N Clean dirty spark plug.
N Check electrode gap (A) and 
readjust if necessary – see chapter 
"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.
Spark Arresting Screen in 
Muffler
Spark Plug
3
2
1
0000-GXX 0537-A0