Maruyama B42L - Cylinder Cooling Fins; Cooling Fin Cleaning; Spark Arrester

Cylinder Cooling Fins
Maintenance Interval
• The cylinder cooling fins should be cleaned after
every 25 hours of operation, or once a week,
whichever comes first.
• Air must flow freely around and through the cyl-
inder cooling fins to prevent engine overheating.
Leaves, grass, dirt and debris buildup on the fins
will increase the operating temperature of the
engine, which can reduce engine performance and
shorten engine life.
Cooling Fin Cleaning
1. With the engine at ambient (room) temperature,
loosen the knob and remove the air filter cover.
2. Loosen the knob and lift off the cylinder cover.
3. Clean all dirt and debris from the cooling fins and
from around the cylinder base.
4. DO NOT overlook cleaning of the cooling air
intake area below the crankcase and above the
fuel tank! This area must be free of debris and
obstruction for the engine to cool properly.
5. Reinstall the cylinder cover.
Spark Arrester
Maintenance Interval
• The spark arrester should be inspected and cleaned
after every 25 hours of use.
• Replace the screen if it cannot be thoroughly
cleaned, or if it is damaged.
Spark Arrester Maintenance
1. With the engine at ambient (room) temperature,
loosen the knob and remove the air cleaner cover.
2. Loosen the knob and lift off the cylinder cover.
3. Remove a screw located on the side of the exhaust
outlet holds the spark arrester in place.
4. Withdraw the spark arrester, using a suitable pair
of pliers.
Note: Do not crush or distort the spark arrester flange
during removal.
5. The screen can be cleaned using a non-flammable
solvent and stiff wire brush.
Note: If any part cannot be thoroughly cleaned, it must
be replaced.
— US-25 —
WARNING
POTENTIAL HAZARD
• Muffler surface becomes hot when
Trimmer/Brushcutter is in operation
and remains hot for some time after the
engine is shut off.
WHAT CAN HAPPEN
• Contact with hot muffler surfaces could
cause a burn.
HOW TO AVOID THE HAZARD
• Make sure the muffler is cool before
inspecting and cleaning the spark
arrester.
Cylinder Cover
Cooling Fins
Knob