Operating Guide

GENERAL SAFETY PRECAUTIONS
14 – English
1153137-95 Rev.2 2009-12-29
recommendation assumes that the length of the
cutting teeth is not reduced excessively.
You will need a flat file and a depth gauge tool. We
recommend that you use our depth gauge tool to
acheive the correct depth gauge setting and bevel for
the depth gauge.
Place the depth gauge tool over the chain. Detailed
information regarding the use of the depth gauge tool,
will be found on the package for the depth gauge tool.
Use the flat file to file off the tip of the depth gauge that
protrudes through the depth gauge tool. The depth
gauge setting is correct when you no longer feel
resistance as you draw the file along the depth gauge
tool.
Tensioning the chain
The more you use a chain the longer it becomes. It is
therefore important to adjust the chain regularly to take up
the slack.
Check the chain tension every time you refuel. NOTE! A
new chain has a running-in period during which you
should check the tension more frequently.
Tension the chain as tightly as possible, but not so tight
that you cannot pull it round freely by hand.
455 Rancher, 460 Rancher
Loosen the bar nuts that hold the clutch cover/chain
brake. Use the combination spanner. Then tighten the
bar nuts by hand as tight as you can.
Raise the tip of the bar and stretch the chain by
tightening the chain tensioning screw using the
combination spanner. Tighten the chain until it does
not sag from the underside of the bar.
Use the combination spanner to tighten the bar nuts
while lifting the tip of the bar at the same time. Check
that you can pull the chain round freely by hand and
that it does not sag from the underside of the bar.
The position of the chain tensioning screw on our chain
saws varies from model to model. See instructions under
the heading What is what? to find out where it is on your
model.
455e Rancher
Release the knob by folding it out.
Turn the knob anti clockwise to loosen the bar cover.
Adjust the tension on the chain by turning the wheel
down (+) for tighter tension and up (-) to loosen the
tension.
!
WARNING! A slack chain may jump off
the bar and cause serious or even fatal
injury.
MAINTENANCE
English 31
1153137-95 Rev.2 2009-12-29
General
The user must only carry out the maintenance and
service work described in this manual. More extensive
work must be carried out by an authorized service
workshop.
Carburetor adjustment
Due to existing environmental and emissions legislation
your chain saw is equipped with movement limiters on the
carburetor adjuster screws. These limit the adjustment
possibilities to a maximum of a 1/2 turn.
Your Husqvarna product has been designed and
manufactured to specifications that reduce harmful
emissions.
Function
The carburetor governs the engine’s speed via the
throttle control. Air and fuel are mixed in the
carburetor. The air/fuel mixture is adjustable. Correct
adjustment is essential to get the best performance
from the machine.
The setting of the carburetor means that the engine is
adapted to local conditions, for example, the climate,
altitude, fuel and the type of 2-stroke oil.
The carburetor has three adjustment controls:
- L = Low speed jet
- H = High speed jet
- T = Idle adjustment screw
The L and H-jets are used to adjust the supply of fuel
to match the rate that air is admitted, which is
controlled with the throttle. If they are screwed
clockwise the air/fuel ratio becomes leaner (less fuel)
and if they are turned anti-clockwise the ratio
becomes richer (more fuel). A lean mixture gives a
higher engine speed and a rich mixture gives a lower
engine speed.
The T-screw regulates the throttle setting at idle
speed. If the T-screw is turned clockwise this gives a
higher idle speed; turning it anti-clockwise gives a
lower idle speed.
Basic settings and running in
The basic carburetor settings are adjusted during testing
at the factory. Avoid running at a too high speed for
extended periods during the first 10 hours.
CAUTION! If the chain rotates while idling the T-screw
must be turned anti-clockwise until the chain stops.
Rec. idle speed: 2700 rpm
Fine adjustment
When the machine has been ”run-in” the carburetor
should be finely adjusted.
The fine adjustment should
be carried out by a qualified person.
First adjust the L-
jet, then the idling screw T and then the H-jet.
Conditions
Before any adjustments are made the air filter should
be clean and the cylinder cover fitted. Adjusting the
carburetor while a dirty air filter is in use will result in
a leaner mixture next time the filter is cleaned. This
can give rise to serious engine damage.
Do not attempt to adjust the L and H jets beyond
either stop as this could cause damage.
Now start the machine according to the starting
instructions and let it warm up for 10 minutes.
Place the machine on a flat surface so that the bar
points away from you and so that the bar and chain do
not come into contact with the surface or other
objects.
Low speed jet L
Turn the low speed jet L clockwise until it stops. If the
engine accelerates poorly or idles unevenly, turn the low
speed jet L anticlockwise until good acceleration and
idling are achieved.
Fine adjustment of the idling speed T
Adjust the idle speed with the T-screw. If it is necessary to
re-adjust, turn the T-screw clockwise while the engine is
running, until the chain starts to rotate. Then turn counter-
clockwise until the chain stops. A correctly adjusted idle
speed setting occurs when the engine runs smoothly in
every position. It should also be good margin to the rpm
when the chain starts to rotate.
High speed jet H
At the factory the engine is adjusted at sea level.
When working at a high altitude or in different
weather conditions, temperatures and atmospheric
humidity, it may be necessary to make minor
adjustments to the high speed jet.
1/2
1/2
H
L
L
H
T
!
WARNING! Contact your servicing
dealer, if the idle speed setting cannot be
adjusted so that the chain stops at idle.
Do not use the chain saw until it has
been properly adjusted or repaired.