Makita DCS 7900 Chainsaw User Manual


 
Replacing the spark plug
CAUTION:
Do
not touch the
spark
plug
or
plug
cap
if
the engine
is
running (high voltage).
Switch off the engine before starting any maintenance
work.
A
hot engine can cause burns. Wear protective
gloves1
The spark plug must be replaced in case of damage
to
the
insulator, electrode erosion (burn) or if the electrodes are very
dirty or oily.
Remove the filter cover (see "Cleaning the air filter").
Pull the plug cap
(6)
off
the spark plug. Use only the combina-
tion wrench supplied with the saw to remove the spark plug.
Electrode gap
The electrode gap must be
.020"
(0.5
mm).
Checking the ignition
spark
Stick the combination tool
(7)
bei;hreen the hood and cylinder
exactly as shown.
IMPORTANT!
Do
not
stick the tool
in
the spark plug hole.
It
should touch
Q&
the cylinder (otherwise the engine will
be damaged!).
With the spark-plug cap firmly attached to the unscrewed spark
plug
(8),
use insulated pliers to hold the plug against the tool
(away from the spark-plug hole!).
Switch the I/STOP ignition switch
(9)
as shown by the arrow.
Pull the starter cable hard.
If
the function is correct, an ignition spark must be visible near
the electrodes.
CAUTION:
Use only the following spark plugs:
NGK BPMR
7A.
J
Do
not tighten the muffler screws when the engine is hot1
Check the muffler screws
(10)
for tightness. If they are loose,
hand-tighten them. Important
-
do not overtighten!
31