Husqvarna 455 Rancher - Manual (Page 19)

English – 19
FUEL HANDLING
Fuel
Note! The machine is equipped with a two-stroke engine and
must always be run using a mixture of petrol and two-stroke
oil. It is important to accurately measure the amount of oil to
be mixed to ensure that the correct mixture is obtained. When
mixing small amounts of fuel, even small inaccuracies can
drastically affect the ratio of the mixture.
Petrol
• Use good quality unleaded or leaded petrol.
• CAUTION! Engines equipped with catalytic
converters must be run on unleaded fuel mixtures.
Leaded gasoline will destroy the catalytic converter and it
will no longer serve its purpose. The green fuel cap on
saws fitted with catalytic converters means that only
unleaded gasoline can be used.
• The lowest recommended octane grade is 90 (RON). If
you run the engine on a lower octane grade than 90 so-
called knocking can occur. This gives rise to a high engine
temperature and increased bearing load, which can result
in serious engine damage.
• When working with continuous high revs (e.g. limbing) a
higher octane is recommended.
Environment fuel
HUSQVARNA recommends the use of alkylate fuel, either
Aspen two-stroke fuel or environmental fuel for four-stroke
engines blended with two-stroke oil as set out below. Note
that carburettor adjustment may be necessary when
changing the type of fuel (see the instructions under the
heading Carburettor).
Running-in
Avoid running at a too high speed for extended periods during
the first 10 hours.
Two-stroke oil
• For best results and performance use HUSQVARNA two-
stroke engine oil, which is specially formulated for our air-
cooled two-stroke engines.
• Never use two-stroke oil intended for water-cooled
engines, sometimes referred to as outboard oil (rated
TCW).
• Never use oil intended for four-stroke engines.
• A poor oil quality and/or too high oil/fuel ratio may
jeopardise function and decrease the life time of catalytic
converters.
Mixing ratio
1:50 (2%) with HUSQVARNA two-stroke oil.
1:33 (3%) with oils class JASO FB or ISO EGB formulated for
air-cooled, two-stroke engines.
Mixing
• Always mix the petrol and oil in a clean container intended
for fuel.
• Always start by filling half the amount of the petrol to be
used. Then add the entire amount of oil. Mix (shake) the
fuel mixture. Add the remaining amount of petrol.
• Mix (shake) the fuel mixture thoroughly before filling the
machine’s fuel tank.
• Do not mix more than one month’s supply of fuel at a time.
• If the machine is not used for some time the fuel tank
should be emptied and cleaned.
Chain oil
• We recommend the use of special oil (chain oil) with good
adhesion characteristics.
• Never use waste oil. This results in damage to the oil
pump, the bar and the chain.
• It is important to use oil of the right grade (suitable
viscosity range) to suit the air temperature.
• In temperatures below 0
°C (32°F) some oils become too
viscous. This can overload the oil pump and result in
damage to the oil pump components.
• Contact your service agent when choosing chain oil.
!
WARNING! Always ensure there is adequate
ventilation when handling fuel.
Petrol, litre Two-stroke oil, litre
2% (1:50) 3% (1:33)
5 0,10 0,15
10 0,20 0,30
15 0,30 0,45
20 0,40 0,60