will not flow into the carburetor, causing prob-
lems with starting or nunning the engine.
At the same time, make sure that the base of
the breather assembly is fitted firmly into the
groove inside the tank cap as shown below.
Fig.11
Breather
passage
AIR CLEANER SERVICE
Clean the air cleaner element every 20 hours.
• Remove the air cleaner cap from the air
cleaner case by removing the air cleaner cap
screw.
• Remove the element from the air cleaner case.
• Wash the element in detergent and water,
and dry it thoroughly.
• Reinstall the element in the air cleaner case
and reinstall the air cleaner, and tighten the
screw (Fig.12).
NOTE: Improper element cleaning can result in
engine damage. Do not use compressed air to
clean or dry element. Always clean element
with an approved high flash point solvent only.
Never use gasoline. Do not operate engine
with air fi Iter parts removed.
Fig.12
Element
FUEL FILTER SERVICE
Every 20 hours of operation.
• Pull the fuel filter out from the fuel tank.
• Clean the fuel filter in a bath of high flash-
point solvent (Fig.13).
• Dry the fuel filter and reinstall it into the fuel
tank.
Fig.13
Fuel filter
18
Tank cap
Breather
assembly
Fuel tank
Air filter case
Air cleaner cap
screw
Air cleaner cap
NOTE: If a fuel still does not flow well after the
cleaning, replace the fuel filter with new one.
IMPORTANT: Many solvents are highly flam-
mable and may cause serious burns. Improper
use of solvents can result in fire or an explo-
sion. Do not use gasoline or low flash-point
solvents to clean the fuel filter. Clean only in
a well-ventilated area away from sources of
sparks or flame, including any appliances with
a pilot light.
SPARK PLUG SERVICE
Every 50 hours of operation
• Take the spark plug cap with fingers, and pull
it up.
• Remove the spark plug by using a suitable
plug wrench.
• Clean the electrodes by scraping or with a
wire brush to remove carbon deposits and
wetness.
• Inspect for cracked porcelain or other wear
and damage. Replace the spark plug with a
new one if necessary.
• Check the spark plug gap and reset it if neces-
sary. The gap must be between 0.6 and 0. 7mm.
To change the gap, bend only side-electrode,
using a spark plug tool.
• Install and tighten the spark plug to 14Nm
(1.4kgfm).
• Fit the spark plug cap on the spark plug se-
curely.
• Pull up the spark plug cap lightly to make
sure of the installation of the spark plug cap.
Recommended spark plug:
DG927, DG935, DG945: NGK BPMR7A
SPARK ARRESTER SERVICE
Every 50 hours of operation
• Remove the spark arrester from the exhaust
hole of muffler.
• Clean deposits from the spark arrester screen
by brushing it.
• Install the spark arrester.
DG953: NGK BPMRBY
Muffler
Spark arrester