Stihl MS 250 Instruction Manual page 42

English
4
3
Place fingers behind the air filter (3),
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press thumbs against the housing,
swing the filter in the direction of the
rear handle and remove it.
Remove the shutter (4).
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Pull off the spark plug boot.
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Unscrew the spark plug.
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40
Checking the Spark Plug
Clean dirty spark plug.
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Check electrode gap (A) and
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readjust if necessary – see
"Specifications".
Rectify the problems which have
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caused fouling of the spark plug.
Possible causes are:
Too much oil in fuel mix.
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Dirty air filter.
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Unfavorable running conditions.
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WARNING
Arcing may occur if the adapter nut (1) is
loose or missing. Working in an easily
combustible or explosive atmosphere
may cause a fire or an explosion. This
can result result in serious injuries or
damage to property.
MS 210, MS 210 C, MS 230, MS 230 C, MS 250, MS 250 C
Use resistor type spark plugs with a
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properly tightened adapter nut.
Installing the spark plug
Screw home the spark plug, fit the
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boot and press it down firmly.
Install the shutter and air filter.
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A
Fit the carburetor box cover.
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1