Husqvarna 450 X Torq Owners Manual

							MAINTENANCE
English – 31115 13 81-26 Rev.3 2009-01-14
General
The user must only carry out the maintenance and 
service work described in this Operator’s Manual. More 
extensive work must be carried out by an authorised 
service workshop.
Carburettor adjustment
Your Husqvarna product has been designed and 
manufactured to specifications that reduce harmful 
emissions. 
Function
•The carburettor governs the engine’s speed via the 
throttle control. Air and fuel are mixed in the 
carburettor. The air/fuel mixture is adjustable. Correct 
adjustment is essential to get the best performance 
from the machine.
• 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 carburettor settings are adjusted during testing 
at the factory. Fine adjustment should be carried out by a 
skilled technician.
Rec. idle speed: See the Technical data section.
Fine adjustment of the idle 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 anti-
clockwise until the chain stops. When the idle speed is 
correctly adjusted the engine should run smoothly in 
every position and the engine speed should be safely 
below the speed at which the chain starts to rotate.
Correctly adjusted carburettor
When the carburettor is correctly adjusted the machine 
accelerates without hesitation and 4-cycles a little at full 
throttle. It is also important that the chain does not rotate 
at idle. If the L-jet is set too lean it may cause starting 
difficulties and poor acceleration. If the H-jet is set too 
lean the machine will have less power, poor acceleration 
and could suffer damage to the engine.
Checking, maintaining and 
servicing chain saw safety 
equipment
Chain brake and front hand guard
Checking brake band wear
Brush off any wood dust, resin and dirt from the chain 
brake and clutch drum. Dirt and wear can impair operation 
of the brake.
Regularly check that the brake band is at least 0.6 mm 
thick at its thinnest point.
Checking the front hand guard
Make sure the front hand guard is not damaged and that 
there are no visible defects such as cracks.
Move the front hand guard forwards and back to make 
sure it moves freely and that it is securely anchored to the 
clutch cover.
!
WARNING! Contact your servicing 
dealer, if the idle speed setting cannot be 
adjusted so that the chain stops. Do not 
use the chain saw until it has been 
properly adjusted or repaired.
Note! All service and repair work on the machine 
demands special training. This is especially true of the 
machine’s safety equipment. If your machine fails any of 
the checks described below we recommend that you 
take it to your service workshop.  
						

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Checking the inertia brake release
Place the chain saw, with the engine switched off, on a 
stump or other stable surface. Release the front handle 
and let the saw fall by its own weight, rotating around the 
rear handle towards the stump.
When the bar hits the stump the brake should be applied.
Checking the brake trigger
Place the chain saw on firm ground and start it. Make sure 
the chain does not touch the ground or any other object. 
See the instructions under the heading Start and stop.
Grasp the chain saw firmly, wrapping your fingers and 
thumbs around the handles.
Apply full throttle and activate the chain brake by tilting 
your left wrist forward onto the front hand guard. Do not let 
go of the front handle. 
The chain should stop 
immediately.
Throttle lockout
•Make sure the throttle control is locked at the idle 
setting when the throttle lockout is released.
• Press the throttle lockout and make sure it returns to 
its original position when you release it.
• Check that the throttle control and throttle lockout 
move freely and that the return springs work properly.
• Start the chain saw and apply full throttle. Release the 
throttle control and check that the chain stops and 
remains stationary. If the chain rotates when the 
throttle control is in the idle position you should check 
the carburettor idle adjustment. 
						

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English – 33115 13 81-26 Rev.3 2009-01-14
Chain catcher
Check that the chain catcher is not damaged and is firmly 
attached to the body of the chain saw.
Right hand guard
Check that the right hand guard is not damaged and that 
there are no visible defects, such as cracks.
Vibration damping system
Regularly check the vibration damping units for cracks or 
deformation.
Make sure the vibration damping units are securely 
attached to the engine unit and handle unit.
Stop switch
Start the engine and make sure the engine stops when 
you move the stop switch to the stop setting.
CAUTION! The start/stop switch automatically returns to 
run position. In order to prevent unintentional starting, the 
spark plug cap must be removed from the spark plug 
when assembling, checking and/or performing 
maintenance. 
Muffler
Never use a machine that has a faulty muffler.
Regularly check that the muffler is securely attached to 
the machine.
Some mufflers are equipped with a special spark arrestor 
mesh. If your machine has this type of muffler, you should 
clean the mesh at least once a week. This is best done 
with a wire brush. A blocked mesh will cause the engine 
to overheat and may lead to serious damage.
Note! The mesh must be replaced if it is damaged. If the 
mesh is blocked the machine will overheat and this will 
cause damage to the cylinder and piston. Never use a 
machine with a muffler that is in poor condition. 
Never  
						

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34 – English115 13 81-26 Rev.3 2009-01-14
use a muffler if the spark arrestor mesh is missing or 
defective.
The muffler is designed to reduce the noise level and to 
direct the exhaust gases away from the operator. The 
exhaust gases are hot and can contain sparks, which may 
cause fire if directed against dry and combustible 
material.
Starter
Replacing the starter cord
•Loosen the screws that hold the starter against the 
crankcase and remove the starter.
• Pull out the cord approx. 30 cm and hook it into the 
notch in the rim of the pulley. Release the recoil spring 
by letting the pulley rotate slowly backwards.
• Undo the bolt in the centre of the pulley and remove 
the drive disc (A), drive disc spring (B) and the pulley 
(C). Insert and secure a new starter cord in the starter 
pulley. Wind approx. 3 turns of the starter cord on the 
starter pulley. Fit the starter pulley so that the end of 
the recoil spring (D) hooks into the starter pulley. Now 
assemble the drive disc spring, drive disc and the bolt 
in the centre of the pulley. Carry the starter cord 
through the hole in the starter housing and the starter 
handle. Tie a good knot on the starter cord.
Tensioning the recoil spring
•Hook the starter cord in the notch in the pulley and 
turn the starter pulley about 2 turns clockwise.
Note! Check that the pulley can be turned at least a 
further 1/2 turn when the starter cord is pulled all the 
way out.
Stretch the line with the handle. Move your thumb and 
release the line. See the figure below.
!
WARNING! When the recoil spring is 
wound up in the starter housing it is 
under tension and can, if handled 
carelessly, pop out and cause personal 
injury.
Care must be exercised when replacing 
the return spring or the starter cord. 
Wear protective glasses and protective 
gloves.
12 
						

							MAINTENANCE
English – 35115 13 81-26 Rev.3 2009-01-14
Replacing the return and drive springs
Recoil spring (A)
•Lift up the starter pulley. See instructions under the 
heading Changing a broken or worn starter cord. 
Remember that the recoil spring is coiled under 
tension in the starter housing.
• Remove the cassette with the recoil spring from the 
starter.
• Lubricate the recoil spring with light oil. Fit the 
cassette with recoil spring in the starter. Fit the starter 
pulley and tension the recoil spring.
Drive disc spring (B)
•Undo the bolt in the centre of the pulley and remove 
the drive disc and the drive disc spring.
• Replace the drive disc spring and fit the drive disc 
above the spring.
Fitting the starter
•To fit the starter, first pull out the starter cord and place 
the starter in position against the crankcase. Then 
slowly release the starter cord so that the pulley 
engages with the pawls.
• Fit and tighten the screws that hold the starter.
Air filter
The air filter must be regularly cleaned to remove dust and 
dirt in order to avoid:
• Carburettor malfunctions
• Starting problems
• Loss of engine power
• Unnecessary wear to engine parts.
• Excessive fuel consumption.
• Remove the air filter after taking off the air filter cover. 
When refitting make sure that the air filter seals tightly 
against the filter holder. Clean the filter by brushing or 
shaking it.
The filter can be cleaned more thoroughly by washing it in 
water and detergent.
An air filter that has been in use for a long time cannot be 
cleaned completely. The filter must therefore be replaced 
with a new one at regular intervals. 
A damaged air filter 
must always be replaced.
A HUSQVARNA chain saw can be equipped with different 
types of air filter according to working conditions, weather, 
season, etc. Contact your dealer for advice.
A
B 
						

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36 – English115 13 81-26 Rev.3 2009-01-14
Spark plug
The spark plug condition is influenced by:
• Incorrect carburettor adjustment.
• An incorrect fuel mixture (too much or incorrect type of 
oil).
• A dirty air filter.
These factors cause deposits on the spark plug 
electrodes, which may result in operating problems and 
starting difficulties.
If the machine is low on power, difficult to start or runs 
poorly at idle speed: always check the spark plug first 
before taking any further action. If the spark plug is dirty, 
clean it and check that the electrode gap is 0.5 mm. The 
spark plug should be replaced after about a month in 
operation or earlier if necessary.
Note! Always use the recommended spark plug type! Use 
of the wrong spark plug can damage the piston/cylinder. 
Check that the spark plug is fitted with a suppressor.
Lubricating the bar tip sprocket
Lubricate the bar tip sprocket each time you refuel. Use 
the special grease gun and a good quality bearing grease.
Needle bearing lubrication
The clutch drum has a needle bearing on the output shaft. 
This needle bearing must be lubricated regularly.
When lubricating, remove the clutch cover by loosening 
the two bar nuts. Lay the saw on its side with the clutch 
drum upwards.
Lubrication involves engine oil dripping into the centre of 
the clutch drum as it rotates.
Cooling system
To keep the working temperature as low as possible the 
machine is equipped with a cooling system.
The cooling system consists of:
1 Air intake on the starter.
2 Air guide plate.
3 Fins on the flywheel.
4 Cooling fins on the cylinder.
5 Cylinder cover (directs cold air over the cylinder).
Clean the cooling system with a brush once a week, more 
often in demanding conditions. A dirty or blocked cooling 
system results in the machine overheating which causes 
damage to the piston and cylinder. 
						

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”Air Injection” centrifugal 
cleaning
Centrifugal cleaning means the following: All air to the 
carburettor passes through the starter. Dirt and dust is 
centrifuged out by the cooling fan.
IMPORTANT! In order to maintain operation of the 
centrifugal cleaning system it must be regularly 
maintained. Clean the air intake to the starter, the fins on 
the flywheel, the space around the flywheel, inlet pipe and 
carburettor compartment.
Winter use
Running problems can occur when using the machine in 
the cold and snowy conditions caused by:
• Too low engine temperature.
• Icing of the air filter and carburettor.
Special measures are therefore often required:
• Partly mask the air inlet on the starter to increase the 
working temperature of the engine.
Temperature -5°° ° °C or colder:
For running the machine in cold weather or powder snow, 
a special cover is available, which is mounted on the 
starter housing. This reduces the intake of cold air and 
prevents large amounts of snow from being sucked in.
CAUTION! If the special winterising kit has been fitted or 
any measures have been taken to increase the 
temperature these changes must be reversed before the machine is used in normal temperature conditions. 
Otherwise there is a risk of overheating, resulting in 
severe damage to the engine.
IMPORTANT! Any maintenance other than that described 
in this manual must be carried out by your servicing dealer 
(retailer). 
						

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MAINTENANCE
115 13 81-26 Rev.3 2009-01-14
Maintenance schedule
The following is a list of the maintenance that must be performed on the machine. Most of the items are described in the 
Maintenance section.
Daily maintenanceWeekly maintenanceMonthly maintenance
Clean the outside of the machine.On chain saws without a catalytic 
converter, check the cooling system 
weekly.Check the brake band on the chain 
brake for wear. Replace when less 
than 0.6 mm (0,024 inch) remains at 
the most worn point.
Check that the components of the 
throttle control work safely. (Throttle 
lockout and throttle control.)Check the starter, starter cord and 
return spring.Check the clutch centre, clutch drum 
and clutch spring for wear.
Clean the chain brake and check that 
it operates safely. Make sure that the 
chain catcher is undamaged, and 
replace it if necessary.Check that the vibration damping 
elements are not damaged.Clean the spark plug. Check that the 
electrode gap is 0.5 mm.
The bar should be turned regularly for 
more even wear. Check the 
lubrication hole in the bar, to be sure it 
is not clogged. Clean the bar groove. 
If the bar has a sprocket tip, this 
should be lubricated.
Lubricate the clutch drum bearing.Clean the outside of the carburettor.
Check that the bar and chain are 
getting sufficient oil.File off any burrs from the edges of 
the bar.Check the fuel filter and the fuel hose. 
Replace if necessary.
Check the saw chain with regard to 
visible cracks in the rivets and links, 
whether the saw chain is stiff or 
whether the rivets and links are 
abnormally worn. Replace if 
necessary.
Clean or replace the spark arrestor 
mesh on the muffler.Empty the fuel tank and clean the 
inside.
Sharpen the chain and check its 
tension and condition. Check the drive 
sprocket for excessive wear and 
replace if necessary.
Clean the carburettor compartment.Empty the oil tank and clean the 
inside.
Clean the starter units air intake.Clean the air filter. Replace if 
necessary.Check all cables and connections.
Check that nuts and screws are tight.
Check that the stop switch works 
correctly.
Check that there are no fuel leaks 
from the engine, tank or fuel lines.
On chain saws with a catalytic 
converter, check the cooling system 
daily. 
						

							English – 39
TECHNICAL DATA
115 13 81-26 Rev.3 2009-01-14
Technical data
Note 1: Noise emissions in the environment measured as sound power (LWA) in conformity with EC directive 2000/14/EC.
Note 2: Equivalent sound pressure level, according to ISO 22868, is calculated as the time-weighted energy total for 
noise pressure levels under various working conditions with the following time distribution: 1/3 idling, 1/3 max. load, 1/3 
max. speed.
Note 3: Equivalent vibration level, according to ISO 22867, is calculated as the time-weighted energy total for vibration 
levels under various working conditions with the following time distribution: 1/3 idling, 1/3 max. load, 1/3 max. speed.
445445e450e
Engine
Cylinder displacement, cm345,745,750,2
Cylinder bore, mm424244
Stroke, mm333333
Idle speed, rpm270027002700
Power, kW/ rpm2,1/90002,1/90002,4/9000
Ignition system
Manufacturer of ignition systemWalbroWalbroWalbro
Type of ignition systemMBU-16MBU-16MBU-16
Spark plugNGK BPMR 7A/ 
Champion RCJ 7Y/ 
Husqvarna PR 17YNGK BPMR 7A/ 
Champion RCJ 7Y/ 
Husqvarna PR 17YNGK BPMR 7A/ 
Champion RCJ 7Y/ 
Husqvarna PR 17Y
Electrode gap, mm0,50,50,5
Fuel and lubrication system
Manufacturer of carburettorZamaZamaZama
Carburettor typeEL 37EL 37EL 37
Fuel tank capacity, litre0,450,450,45
Oil pump capacity at 9,000 rpm, ml/min131313
Oil tank capacity, litre0,260,260,26
Type of oil pumpNot adjustableNot adjustableNot adjustable
Weight
Chain saw without bar or chain, empty tanks, kg4,95,15,1
Noise emissions (see note 1)
Sound power level, measured dB(A)112112113
Sound power level, guaranteed LWA dB(A)114114115
Sound levels (see note 2)
Equivalent sound pressure level at operator’s ear, measured 
according to relevant international standards, dB(A)103103104
Vibration levels (see note 3)
Front handle, m/s21,91,92,3
Rear handle, m/s22,62,62,7
Chain/bar
Standard bar length, inch/cm13/3313/3313/33
Recommended bar lengths, inch/cm13-20/33-5013-20/33-5013-20/33-50
Usable cutting length, inch/cm12-19/31-4912-19/31-4912-19/31-49
Pitch, inch/mm0,325/8,250,325/8,250,325/8,25
Thickness of drive links, inch/mm0,050/1,30,050/1,30,050/1,3
0,058/1,50,058/1,50,058/1,5
Type of drive sprocket/number of teethSpur/7Spur/7Spur/7
Chain speed at max. power, m/sec17,317,317,3 
						

							40 – English
TECHNICAL DATA
115 13 81-26 Rev.3 2009-01-14
Bar and chain combinations
The following combinations are CE approved.
Saw chain filing and file gauges
BarChain
Length, inchPitch, inchGauge, mmMax. nose radiusTypeLength, drive links (no.)
130,325
1,3
10T
Husqvarna H30
56
150,32510T64
160,32510T66
180,32510T72
200,32510T78
130,325
1,5
10T
Husqvarna H25
56
150,32510T64
160,32510T66
180,32510T72
200,32512T78