Checking The Spark Plug - Stihl MS 380 Manual

English
Erratic idling behavior, poor
acceleration
(even though the low speed screw is
opened one turn)
Idle setting is too lean.
: Turn the low speed screw (L)
counterclockwise until 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).
32

Checking the Spark Plug

If engine is down on power, difficult to
start or runs poorly at idle speed, first
check the spark plug.
:
Remove the spark plug –
see "Starting / Stopping the Engine".
:
Clean dirty spark plug.
: Check electrode gap (A) and
readjust if necessary – see
"Specifications".
: Rectify the problems which have
caused fouling of spark plug:
– To much oil in fuel mix.
– Dirty air filter.
– Unfavorable running conditions.
:
Fit a new spark plug after
about 100 operating hours – or
sooner if the electrodes are badly
eroded.
Install only suppressed spark plugs
of the type approved by STIHL –
see "Specifications".
To reduce the risk of arcing
and fire:
: If the spark plug comes with a
detachable adapter nut (1), screw it
on firmly.
1
MS 380