Muffler; Cooling System; Spark Plug - Husqvarna 325HS75 Operator's Manual

Muffler

NOTE!
Some mufflers are fitted with catalytic converters. See "Techni-
cal data" to find out if your machine is equipped with a
catalytic converter.
The muffler is designed to
dampen the noise level and
to direct the exhaust fumes
away from the user. The
exhaust fumes are hot and
can contain sparks, which
can result in fire if the
exhaust fumes are directed
towards a dry and inflam-
mable material. Some
mufflers are equipped with a
special spark arrest screen. If
your machine is fitted with
this type of screen it should
be cleaned regularly. This is
done using a wire brush. On
mufflers without a catalytic
converter the screen should
be cleaned weekly, or
replaced if necessary. On
mufflers fitted with a
catalytic converter the
screen should be checked
and cleaned monthly. If the
screen is damaged it should
be replaced. If the screen is
frequently blocked, this can
be a sign that the function
of the catalytic converter is
impaired. Contact your
dealer to inspect the muffler.
A blocked screen will cause
the engine to overheat
resulting in damage to the
cylinder and piston. Also see
under "Maintenance".
NOTE!
Never use a machine with a
defective muffler.
!
WARNING!
Mufflers fitted with catalytic converters
become extremely hot during use and
after stopping. This also applies at idling
speeds. Contact can result in burns to
the skin. Be observant to the risk of fire!
16
– English
MAINTENANCE

Cooling system

To maintain as low operat-
ing temperature as possible
the engine is equipped with
a cooling system.
The cooling system consists
of:
1. An air intake on the
starter unit.
2. Cooling fins on the
flywheel.
3. Cooling fins on the
cylinder
4. Cylinder cover (leads
cold air onto the
cylinder).
Clean the cooling system
using a brush at least once a
week, in difficult conditions
more often.
A dirty or blocked cooling
system leads to the engine
overheating resulting in
damage to the cylinder and
piston.

Spark plug

The condition of the spark
plug is affected by:
• An incorrect carburettor
setting.
• An incorrect fuel mixture
(too much or faulty oil).
• A dirty air filter.
These factors cause deposits
on the spark plug electrode
that may result in malfunc-
tion or starting difficulties.
If the machine is low on
power, difficult to start or
runs poorly while idling
always check the spark plug
first before taking other
action.
If the spark plug is dirty,
clean it and at the same time
check that the electrode gap
is 0.5 mm. The spark plug
should be changed after
about one month of opera-
tion or earlier if necessary.
NOTE! Always use the
recommended type of spark
plug. An incorrect spark plug
can damage the cylinder/
piston.
1 2
3 4
0,5 mm