McCulloch MAC 742, MAC 738, MAC 740 User Manual

INSTRUCTION MANUAL

IMPORTANT INFORMATION: Please read these instr uctions carefull y

GB

and make sure you understand them before using this unit. Re t a in these
instructions for future refer ence.

MANUEL D’INSTRUCTIONS

RENSEIGNEMENTS IMPORTANTS:Avant d’utiliser cet appareil,

FR

veuillez lire atentivementles instructionset assurez--vous de les avoir
comprises. Conservezles instructionspour référence ultérieure.

BETRIEBSANWEISUNG
WICHTIGE INFORMATION: Lesen Sie diese Hinweise zur Handha-

DE

bung des Geräts aufmerksam durch. Verwenden Sie es erst, wenn
Sie s icher sind, daß Sie alle Anweisungen verstanden haben und
gut aufbewahren.

MANUAL DE INSTRUCCIONES

INFORMACIÓNIMPORTANTE: Lea atentamente las instruccionesy

ES

asegúrese de entenderlas antes de utilizar esta aparato. Conserve las
instrucciones para la referenciaen el futuro.

115162826 Rev. 1 7/15/09 BRW

Chain

Adjustment Tool

(Bar Tool)

Bumper
spike

Throttle
Lockout

Rear
Handle

IDENTIFICATION (WHAT IS WHAT?)

Front Hand Guard

Chain

Bar Oil Fill Cap

Cylinder Cover

Muffler

Starter Housing

Front Handle

Starter Rope

Fuel Mix Fill Cap

Chain
Brake

Adjusting Screw

Idle Speed Screw

ON/STOP
Switch

Choke/
Fast Idle
Lever

Primer Bulb

Chain
Direction
of Travel

Throttle
Trigger

Chain

ClutchCover

Bar Nuts

Catcher

IDENTIFICATION OF SYMBOLS

WARNING! This chain

saw can be dangerous! Care­less or improper use cancause
serious or even fatal injury.

Always wear appropriateear
protection, eye protection
and head protection.

Always use two
hands when
operating the
chain saw.

WARNING! Contacting the guide bar tip with any object

should be avoided; tip contact may cause the guide bar to
movesuddenlyupwardand backward,whichmay causese­rious injury.

2

Guide Bar

Read and understand the
instruction manual before
using the chain saw.

Sound power level

Sound pressure level
at 7,5 meters

Starting Reminder

IDENTIFICATION OF SYMBOLS

Move ON/STOP switch to
the ON position.

Slowly press primer bulb
6times.

Pull choke/fast idle lever
out to the full extent (to
the FULL CHOKE posi­tion).

SAFETY RULES

WARNING: Always disconnect

spark plug wire and place wire where it can­not contact spark plug to prevent accidental
starting when setting up, transporting, ad­justing or making repairs except carburetor
adjustments.
Because a chain saw is a high-speed wood­cutting tool, special safety precautions must
be observed to reduce the risk of accidents.
Careless or improper use of this tool can
cause serious injury.

PLAN AHEAD

S Read this manual carefully until you com-

pletely understand and can follow all safety
rules, precautions, and operating instruc­tions before attempting to use the unit.

S Restrict the use of your saw to adultusers

who understand and can follow safety
rules, precautions, and operating instruc­tions found in this manual.

Hearing

Protection

Snug
Fitting

Clothing

Safety
Shoes

S Wearprotective gear. Always use steel-toed

safety footwear with non-slip soles; snug-fit­ting clothing; heavy-duty, non-slip gloves;
eye protection such as non-fogging, vented
goggles or face screen; an approved safety
hard hat; and sound barriers (ear plugs or
mufflers) to protect your hearing. Secure hair
above shoulder length.

Safety Hat

Eye
Protection

Heavy Duty
Gloves

Safety Chaps

Pull the starter rope
sharply 5 times with your
right hand.

Push the choke/fast idle
lever in to the HALF
CHOKE position.

Pull the starter rope sharply
with your right hand until
the engine starts.

S Always use approved hearing protection.

Regular users should have hearing
checked regularly as chain saw noise can
damage hearing. Long--term exposure to
noise can result in permanent hearing im­pairment.

S Keep all parts of your body away from the

chain when the engine is running.

S Keep children, bystanders, and animals a

minimumof 10 meters away from the work
area. Do not allow other people or animals
to be near the chain saw when starting or
operating the chain saw.

S Do not handle or operate a chain saw

whenyouare fatigued,ill, or upset, or ifyou
have taken alcohol, drugs, or medication.
You must be in good physical condition
and mentally alert. Chain saw work is
strenuous. If you have any condition that
might be aggravated by strenuous work,
check with your doctor before operating a
chain saw.

S Carefullyplan your sawingoperation inad-

vance. Donot startcuttinguntilyou havea
clear work area, securefooting,and,ifyou
are felling trees, a planned retreat path.

OPERATE YOUR SAW SAFELY

WARNING: Long term inhalation of

the engine’s exhaust fumes, chain oil mist and
dust from sawdust can result in serious per­sonal injury.
S Donot operate a chain sawwith one hand.

Serious injury to the operator, helpers, by­standers or any combination of these per­sons may result from one-handed opera­tion. A chain saw is intended for
two-handed use.

S Operatethe chainsaw only in a well-venti-

lated outdoor area.

S Do not operate saw from a ladder or in a

tree, unless you are specifically trained to
do so.

3

S Makesure the chain will not make contact

with any object while starting the engine.
Never try to start the saw when the guide
bar is in a cut.

S Do not put pressureon the saw at the end of

the cut. Applying pressure can cause you to
lose control of the chain saw when the cut is
completed and may cause serious personal
injury.

S Stopthe engine before settingthe saw down.
S Do not operate a chain saw that is dam-

aged, improperly adjusted, or not com­pletely and securely assembled. Always
replace bar, chain, hand guard, or chain
brake immediately ifit becomes damaged,
broken or is otherwise removed.

S With the engine stopped, hand carry the

chain saw with the muffler away from your
body, and the guide bar and chain to the
rear, preferably covered with a scabbard.

CHAIN SAW SAFETY EQUIPMENT

In this section, the safety features of

NOTE:

the chain saw and their function are explained.
For inspection and maintenance, see instruc­tions in the CHECKING, MAINTAINING AND
SERVICING CHAIN SAW SAFETY EQUIP­MENT section. See instructions under the
WHAT IS WHAT? section, to find where these
parts are located on your chain saw. The life
span of the machinecan bereduced and the
risk of accidents can increase if machine
maintenance is not carried out correctly and
if service and/or repairs are not carried out
professionally. If you need further informa­tion, please contact your nearest service
dealer.
S Chain brake. Yourchain saw is equipped

with a chain brake that is designed to stop
the chain from moving.

WARNING: The chain brake is de-

signed to stop the chain immediately if you
get a kickback. Thechain brake reducesthe
risk of accidents, but only you can prevent
them.DONOTASSUMETHATTHECHAIN
BRAKE WILL PROTECT YOU IN THE
EVENT OF A KICKBACK.
S Throttle trigger lock--out. The throttle

lock--out is designed to prevent accidental
operation of the throttle trigger.

S Chain catcher. The chain catcher is de-

signed to catch the saw chain if it breaks.

S Vibration damping system. Your chain

saw is equipped with a vibration damping
systemthatis designed to minimize vibra­tion and make operation easier.

SAFETY NOTICE: Exposure to vibrations

through prolonged use of gasoline powered
hand tools could cause blood vessel or nerve
damageinthe fingers, hands, and joints ofpeo­ple prone to circulation disorders or abnormal
swellings. Prolonged use in cold weather has
been linked to blood vessel damage in other­wise healthy people. If symptoms occur such
as numbness, pain, loss of strength, change in
skin color or texture, or loss of feeling in the fin­gers, hands, or joints, discontinue the use of
this tool and seek medical attention. An anti­vibration system does notguarantee the avoid-

ance of these problems. Users who operate
power tools on a continual and regular basis
must monitor closely their physical condition
and the condition of this tool.
S ON/STOPswitch. TheON/STOPswitch

should be used to stop the engine.

CHECKING, MAINTAINI NG AND
SERVICING CHAIN SAW SAFETY
EQUIPMENT

WARNING: Never use a chain saw

with defective safety equipment. Safety
equipment must be inspected and main­tained. If your chain saw does not pass in­spection, take the saw to your nearest ser­vice dealer for repair.
S Chain brake. Brush off any wood dust,

resin and dirt from the chain brake and
clutch drum. Dirt and wear can impair op­eration of the brake. For additional infor­mation, see OPERATING YOUR UNIT
section.

S Throttletriggerlock--out. Checkthatthe

throttletrigger cannot beoperateduntilthe
throttle lock--out is pressed.

S Chain catcher. Check that the chain

catcher is not damaged and is firmly at­tached to the body of the chain saw.

S 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.

S ON/STOP switch. Start the engine and

make sure the engine stops when you
move the ON/STOP switch to the STOP
position.

MAINTAIN YOUR SAW IN GOOD
WORKING ORDER

S Have all chain saw service performed by a

qualified service dealer with the exception of
the items listed in the maintenancesection of
this manual. For example, if improper tools
are used to remove or hold the flywheel
when servicing the clutch, structural damage
to the flywheel can occur and cause the fly­wheel to burst.

S Make certain the saw chain stops moving

when the throttle trigger is released. For
correction, refer to CARBURETOR AD­JUSTMENTS.

S Never modify your saw in any way. Use

only attachments supplied or specifically
recommended by the manufacturer.

S Keepthe handles dry, clean, andfree ofoil

or fuel mixture.

S Keep fuel and oil caps, screws, and fas-

teners securely tightened.

S Use only McCullochR accessories andre-

placement parts as recommended.

HANDLE FUEL WITH CAUTION

S Do not smoke while handling fuel or while

operating the saw.

S Eliminate all sources of sparks or flame in

the areas where fuel is mixed or poured.
Thereshouldbeno smoking, open flames,
orworkthatcouldcausesparks. Allowen­gine to cool before refueling.

4

S Mix and pour fuel in an outdoor area on bare

ground; store fuel in a cool, dry, well venti­lated place; and use an approved, marked
container for all fuel purposes. Wipe up all
fuel spills before starting saw.

S Mo v eat least 10 feet (3 meters) from fuel-

ing site before starting engine.

S Turn the engine off and let saw cool in a

non-combustible area, not on dry leaves,
straw, paper, etc. Slowly remove fuel cap
and refuel unit.

S Storetheunitandfuelin anareawherefuel

vapors cannot reach sparks or open
flamesfrom water heaters, electric motors
or switches, furnaces, etc.

KICKBACK

WARNING: Avoid kickback which

can result in serious injury. Kickback is the
backward, upwardorsuddenforwardmotion
of the guide bar occurring when the saw
chainneartheupper tip of theguidebar con­tacts any object such as a log or branch, or
when the wood closes in and pinches the
saw chain in thecut.Contactingaforeignob­ject in the wood can also result in loss of
chain saw control.
S Rotational Kickback can occurwhenthe

moving chain contacts an objectat theup­per tip of the guide bar. This contact can
cause the chain to dig into the object,
which stops the chain for an instant. The
result is a lightning fast, reverse reaction
which kicks the guide bar up and back to­ward the operator.

S Pinch-Kickback can occur when the the

wood closes in and pinches the moving
saw chain in the cut along the top of the
guide bar and the saw chain is suddenly
stopped. This sudden stopping of the
chain results in a reversal of the chain
force used to cut wood and causes the
sawtomove inthe opposite direction ofthe
chain rotation. The saw is driven straight
back toward the operator.

S Pull-In can occur when the moving chain

contacts a foreign object in the wood in the
cut along the bottom of the guide bar and the
saw chain is suddenly stopped. This sudden
stopping pulls the saw forward and away
from the operator and could easily cause the
operator to lose control of the saw.

Avoid Pinch--Kickback:

S Be extremely aware of situations or obstruc-

tions that can cause material to pinch the top
of or otherwise stop the chain.

S Do not cut more than one log at a time.
S Do not twist the saw as the bar is with-

drawn from an undercut when bucking.

Avoid Pull--In:

S Always begin cutting with the engine at full

speed and the saw housing againstwood.

S Use wedges made of plastic or wood.

Never use metal to hold the cut open.

Kickback Path

Avoid Obstructions

Clear The
WorkingArea

REDUCETHECHANCEOF
KICKBACK

S Recognize that kickback can happen.

With a basic understanding of kickback,
you can reduce the element of surprise
which contributes to accidents.

S Neverletthemoving chain contact any ob-

ject at the tip of the guide bar.

S Keep the working area free from obstruc-

tions such as other trees, branches, rocks,
fences, stumps, etc. Eliminate or avoid any
obstruction that your saw chain could hit
while you are cutting through a particular log
or branch.

S Keep your saw chain sharp and properly

tensioned. A looseordullchain can increase
the chance of kickback occurring. Follow
manufacturer’s chain sharpening and main­tenance instructions. Check tension atregu­lar intervals with the engine stopped, never
with the engine running. Make sure the bar
clamp nuts are securely tightened after ten­sioning the chain.

S Begin and continue cutting at full speed. If

the chain is moving at a slower speed, there
is greater chance of kickback occurring.

S Cut one log at a time.
S Use extreme caution when re-entering a

previous cut.

S Do not attempt cuts starting with the tip of

the bar (plunge cuts).

S Watch for shifting logs or other forces that

could close a cut and pinch or fall into chain.

S Use the Reduced--Kickback Guide Bar

and Low--Kickback Chain specified for
your saw.

MAINTAIN CONTROL

Stand to the left of
the saw

Never reverse
hand positions

5

K

Symmetrical Guide Bar

L

Elbow locked

Thumb on underside of
handlebar

S Keep a good, firm grip on the saw with both

hands when the engine is running and don’t
let go. A firm grip will help you reduce kick­back and maintain control of the saw. Keep
the fingers of your left hand encircling and
your left thumb under the front handlebar.
Keep your right hand completely around the
rear handle whether your are right handed or
left handed. Keep your left arm straight with
the elbow locked.

S Position your left hand on the fronthandle-

bar so it is in a straight line with your right
hand on the rear handle when making
bucking cuts. Never reverse right and left
hand positions for any type of cutting.

S Standwithyourweightevenlybalancedon

both feet.

S Stand slightly to the left side of the saw to

keep your body from being in a direct line
with the cutting chain.

S Do not overreach. You could be drawn or

thrown off balance and lose control of the
saw.

S Donot cut aboveshoulderheight. Itisdiffi-

cult to maintain control of saw above
shoulder height.I

KICKBACK SAFETY FEATURES

WARNING: The following features are

included on your saw to help reduce the hazard
of kickback; however, such features will not to­tally eliminate this dangerous reaction. As a
chain saw user, do not rely only on safety de­vices. You must follow all safety precautions,
instructions, and maintenance in this manualto
help avoid kickback and other forces which
can result in serious injury.
S Reduced--Kickback Guide Bar, designed

with a small radius tip which reduces the
size of the kickback danger zone on the
bar tip.A Reduced--Kickback Guide Barhas
been demonstrated to significantly reduce
the number and seriousness of kickbacks.

ickback

Reduced
Symmetri cal
Guide B ar

Large Radius Tip

S Low--Kickback Chain, designed with a

contoured depth gauge and guard link
which deflect kickback force and allow
wood to gradually ride into the cutter.

ow-Kickback Chain

Contoured Depth Gauge

Elongated Guard Link
Deflects Kickback
Force And Allows
Wood ToGradually
Ride Into Cutter

S Handguard, designed to reduce the chance

of your left hand contacting the chain if your
hand slips off the front handlebar.

S Position of front and rear handlebars, de-

signedwithdistance between handlesand
“in-line” with each other. The spread and
“in-line” position of the hands provided by
this design work together to give balance
and resistance in controlling the pivot of
the saw back toward the operator if kick­back occurs.

WARNING: DO NOT RELY UPON

ANYO F THE DEVICES BUILTINTOYOUR
SAW. YOU SHOULD USE THE SAW
PROPERLY AND CAREFULLY TO AVOID
KICKBACK. Reduced--kickback guide bars
and low--kickback saw chains reduce the
chance and magnitude of kickback and are
recommended. Yoursaw has a low kickback
chainandbaras original equipment. Repairs
on a chain brake should be made by an au­thorized servicing dealer. Take your unit to
the place of purchase if purchased from a
servicingdealer, ortothenearest authorized
master service dealer.
S Tipcontactinsomecases may cause a light-

ning fast reverse REACTION, kicking the
guide bar up and back toward the operator.

S Pinchingthe sawchainalongthetop of the

guide bar may push the guide bar rapidly
back toward the operator.

S Eitherof thesereactions maycause youto

lose control of the saw which could result
in serious injury. Do not rely exclusively
uponthesafety devices built into your saw.

Small Radius Tip

6

ASSEMBL Y

A

veL

Protective gloves (not provided) should be
worn during assembly.

ATTACH I N G THE BUMPER SPIKE

The bumper spike may be used as a pivot
when making a cut.

1. Loosen and remove the bar nuts andthe
clutchc over fromthe s aw.

2. Attach the bumper spike with the two
screws as illustrated.

4. Turn the adjusting screw by hand coun­terclockwise until the adjusting pin just
touches the stop. This should allow the
pin to be near the correct position.

5. Slide guide bar on bar bolts until guide bar
stops against clutch drum sprocket.

ATTACHING THE BAR & CHAIN

(If not already attached)

WARNING: Recheck each assem-

blystep ifthesaw isreceived assembled.Al­ways wear gloves when handling the chain.
The chain is sharp and can cut you even
when it is not moving!

1. Loosen and remove the bar nuts andthe
clutchc over fromthe s aw.

2. Remove the plastic shipping spacer (if
present).

Clutch cover

Bar nuts

Chain adjustment tool

(Bar Tool)

3. An adjusting pin and screw is used to ad­just the tension of the chain. It is very im­portant when assembling the bar, that the
pin located on the adjusting screw aligns
intoaholein thebar.Turning the screw will
move the adjustment pin up and down the
screw. Locate this adjustment before you
begin mounting the bar onto the saw. See
following illustration.

Adjustment located on clutch cover

Location of
shipping
spacer

Inside
view of
clutch
cover

Bar bolts

Guide bar

6. Carefully remove the chain from the pack­age. Hold chain with the drive links as
shown.

Tip of
Bar

CUTTERS MUST FACE IN

DIIRECTION OF ROT

Cutters

Dri

7. Place chain over and behind clutch re­tainer, fitting the drive links in the clutch
drumsprocket.

8. Fit bottom of drive links between the
teeth in the sprocket in the nose of the
guide bar.

9. Fit chain drive links into bar groove.

10. Pullguide bar forward until chain is snug
inguide bargroove. Ensure alldrivelinks
are in the bar groove.

11. Now,install clutchcover making surethe
adjusting pin is positioned in the lower
hole inthe guidebar. Remember this pin
moves the bar forward and backward as
the screw is turned.

TION

Depth Gauge

inks

7

Clutch

e

Cover

1. Loosen bar nuts until theyare finger tight
against the clutch cover.

2. Turn adjusting screw clockwise until chain
solidly contacts bottom of guide bar rail.

Adjusting

Screw

Adjusting Pin

12. Install bar nuts and finger tighten only.
Once the chain is tensioned, you will
need to tighten bar nuts.

Lower

Hole

Guide Bar

CHAIN TENSION (Including units
with chain already installed)

WARNING: Wear protective gloves

whenhandlingchain. Thechainis sharpand
can cut you even when it is not moving.

NOTE: When adjusting chain tension,

make sure the bar nuts are finger tight only.
Attemptingto tension the chain when thebar
nuts are tight can cause damage.

Checking the tension:

Use the screwdriver end of the chain adjust­ment tool (bar tool) to move chain around
guidebar. If thechain does notrotate,itis too
tight. Ifthe chain is tooloose, itwillsagbelow
the bar.

Guid

Bar

Chain Adjustment

Bar Nuts

Adjusting the tension:

Chain tension is very important. Chains
stretch during use. This is especially true
during the first few times you use your saw.
Always check chain tension each time you
use and refuel your saw.

Adjusting

Screw

Tool

(Bar Tool)

3. Using bar tool, roll chain around guide bar
to ensure all links are in bar groove.

4. Lift up tip of guide bar to check for sag.
Release tipofguidebar,thenturnadjust­ingscrew
til sag does not exist.

5. While lifting tip of guide bar, tighten bar
nuts securely with the bar tool.

6. Use the screwdriver end of thebar tool to
move chain around guide bar.

7. If chain does not rotate, it is too tight.
Slightly loosenbarnutsand loosen chain
by turning the adjusting screw
counterclockwise. Retighten bar nuts.

8. If chain is too loose, it will sag below the
guidebar.DO NOToperatethe saw if the
chain is loose.

WARNING: If the saw is operated

with a loose chain, the chain could jump off
the guide bar and result in serious injury.

WARNING: Muffleris very hotduring

and after use. Donot touch the muffler or al­low combustible material such as dry grass
or fuel to do so.

1

/4turnclockwise. Repeatun-

1

Adjusting Screw --

/4Turn

Bar Nuts

1

/4turn

OPERATING YOUR UNIT

BEFORE STARTING ENGINE

WARNING: Be sure to read the fuel

informationinthe safety rules before yoube­gin.Ifyoudonot understand thesafety rules,
do not attempt to fuel your unit. Contact an
authorized service dealer.

BAR AND CHAIN LUBRICATION

The bar and chain require continuous lubri­cation. Lubrication is provided by the auto­matic oiler system when the oil tank is kept

filled. Lack of oil will quickly ruin the bar and
chain. Too little oil will cause overheating
shown by smoke comingfromthe chain and/
or discoloration of the bar. Only use Bar and
Chain Oil for bar and chain lubrication.

FUELING ENGINE

WARNING: Remove fuelcap slowly

when refueling.
This engine is certified to operate on unleaded
gasoline. Before operation, gasoline must be

8

mixed with a good quality 2-cycle air-cooled
engine oil designed to be mixed at a ratio of
40:1. A 40:1 ratio is obtained by mixing 0,125
liter of oil with 5 liters of unleaded gasoline. DO
NOT USE automotive or boat oil. These oils
will cause engine damage. When mixing fuel
follow the instructions printed on the container.
Always read and follow the safety rules relating
to fuel before fueling your unit.

IMPORTANT

Experienceindicates that alcohol blended fuels
(called gasohol or using ethanol or methanol)
can attract moisture which leads to separation
and formation of acids during storage. Acidic
gas can damage the fuel system of an engine
while in storage. T o avoid engine problems,
empty the fuel system before storage for 30
days or longer.Drain the gas tank, start the en­gine and let it run until the fuel lines and carbu­retor are empty. Use fresh fuel next season.
Never use engine or carburetor cleaner prod­ucts in the fuel tank or permanent damagemay
occur.

CHAIN BRAKE

Ensure chain brake is disengaged by pulling
the front hand guard back toward the front han­dle as far as possible. The chainbrake mustbe
disengaged before cutting with the saw.

WARNING: The chain must not

move when the engine runs at idle speed. If
the chain moves at idle speed refer to CAR­BURETOR ADJUSTMENT within this
manual. Avoid contact with the muffler.Ahot
muffler can cause serious burns.
To stop the engine, move the ON/STOP
switch to the STOP position.
To start the engine, hold the saw firmly on
the ground as illustrated below. Make sure
the chain is free to turn without contacting
any object.

Use only 40 --- 45 cm of rope per pull.

Hold saw firmly while pulling starter rope.

Starter Rope Handle

NOTE:Do not cut material with the choke/fast

idle lever at the FULL CHOKE position.

STARTING A COLD ENGINE (or a
warm engine after running out of
fuel)

:Inthefollowingsteps,whenthecho-

NOTE

ke/fast idle lever is pulled out to the full ex­tent, the correct throttle setting for starting is
set automatically.

IGNITION

SWITCH

ON

STOP

Choke
Lever

1. Move ON/STOP switch to the ON posi­tion.

2. Slowly press primer bulb 6 times.

3. Pull out choke/fast idle to the full extent
(to the FULL CHOKE position).

4. Pull the starter rope sharply 5 times with
your right hand. Then, proceed to the
next step.

NOTE: If the engine sounds as if it is trying

to start before the 5th pull, stop pulling and
immediately proceed to the next step.

5. Push the choke/fast idle lever in to the
HALF CHOKE position.

CHOKE/FAST IDLE LEVER

OFF

HALF

FULL

Left Hand
on Front
Handle

Right Foot Through Rear Handle

IMPORTANT POINTS TO REMEMBER

Whenpullingthestarter rope, do not use thefull
extent of the rope as this can cause the rope to
break. Do not let starter rope snap back. Hold
the handle and let the rope rewind slowly.
For cold weather starting, start the unit at full
choke; allow the engine to warm up before
squeezing the throttle trigger.

6. Pull the starter rope sharply with your
right hand until the engine starts.

7. Allow the enginetorunforapproximately
30 seconds. Then, squeeze andrelease
throttletrigger to allow engineto returnto
idle speed.

STARTING A WARM ENGINE

1. Move ON/STOP switch to the ON posi­tion.

2. Pull the choke/fast idle lever out to the
FULL CHOKE position to set the fast
idle, then push the lever in to the HALF
CHOKE position.

3. Slowly press the primer bulb 6 times.

4. Pull the starter rope sharply with your
right hand until the engine starts.

5. Squeeze and release throttle trigger to
allow engine to return to idle speed.

9

DIFFICULT STARTING (or starting a
flooded engine)

The engine may be flooded with too much
fuel if it has not started after 10 pulls.
Flooded engines can be cleared of excess
fuel by pushing the choke/fast idle lever in
completely (to the OFF CHOKE position)
and then following the warm engine starting
procedure listed above. Ensure the ON/
STOP switch is in the ON position.
Startingcould require pulling the starterrope
handle many times depending on how badly
the unit is flooded. If engine fails to start, re­fer to the TROUBLESHOOTING TABLE.

CHAIN BRAKE

WARNING: If the brake band is worn

too thin it may break when the chain brake is
triggered. With a broken brake band, the chain
brake will not stop the chain. The chain brake
should be replaced by an authorized service
dealer if any part is worn to less than 0,02″ (0,5
mm) thick. Repairs on a chain brake shouldbe
made by an authorized service dealer. Take
your unit to the place of purchase if purchased
from a servicing dealer,or to the nearestautho­rized master service dealer.
S This saw is equipped with a chain brake.

The brake is designed to stop the chain if
kickbackoccurs.

S Theinertia activated chainbrake is activated

if the front hand guard is pushed forward, ei­ther manually or by centrifugal force.

S Ifthe brake is already activated, it isdisen-

gagedby pulling the front hand guard back
toward the front handle as far as possible.

S Whencutting with the saw,thechainbrake

must be disengaged.

Disengaged

Engaged

Braking function control

CAUTION:

checked several times daily. The engine
mustberunning when performing thisproce­dure. This is theonly instance when the saw
should be placed on the ground with the en­gine running.
Place the saw on firm ground. Grip the rear
handlewith your righthand and thefronthan­dle with your left hand. Apply full throttle by
fully depressing the throttle trigger. Activate
the chain brake by turning your left wrist
against the hand guard without releasing
your grip around the front handle. The chain
should stop immediately.

The chain brake must be

Inertia activating function control

WARNING: When performing the fol-

lowing procedure, the engine must be turned
off.
Grip the rear handle with yourright hand and
the front handle with your left hand. Hold the
chain saw approximately 35 cm above a
stump or other wooden surface. Release
your grip on the front handle and use the
weight of the saw to let the top of the guide
bar fall forward and contact the stump.
When the tip of the bar hits the stump, the
brake should activate.

CUTTING METHODS

IMPORTANT POINTS

S Check chain tension before first use and af-

ter 1 minute of operation. See CHAIN TEN­SION in the ASSEMBLY section.

S Cut wood only. Do not cut metal, plastics,

masonry, non-wood building materials, etc.

S The bumper spike may be used as a pivot

when making a cut.

S Stop the saw if the chain strikes a foreign

object. Inspectthesawandrepair parts as
necessary.

S Keepthechainout ofdirtand sand. Evena

smallamountof dirt willquickly dull achain
and increase the possibility of kickback.

S Practice cutting a few small logs using the

following techniques toget the “feel” of us­ing your saw before you begin a major
sawing operation.
S Squeeze the throttle trigger and allow the

engine to reach full speed before cutting.

S Begin cutting with the saw frame

against the log.

S Keep the engine at full speed the entire

time you are cutting.

S Allow thechainto cutforyou.Exertonly

light downward pressure.

S Release the throttle trigger as soon as

the cut is completed, allowing the en-

gine to idle. If you run the saw at full
throttlewithout acutting load,unneces­sary wear can occur.

S To avoid losing control when cut is com-

plete, do not put pressure on saw at end
of cut.

S Stopthe engine before settingthe saw down.

TREE FELLING TECHNIQUES

WARNING: Felling a tree requires

chain saw skills and experience. Inexperi­enced users should not felltrees. Do not at­tempt any task that makes you feel uncom­fortable or unsure.

WARNING: Donotcutnear buildings

or electrical wires if you do not know the di­rection of tree fall, at night since you will not
be able to see well, or during bad weather
such as rain, snow, or strong winds. as fall is
unpredictable.
Carefully plan your sawing operation in ad­vance. You need a clear area all around the
tree so youcan have secure footing. Check
for broken or dead branches which can fall
on you causing serious injury.

10

Natural conditions that can cause a tree to
fall in a particular direction include:

S The wind direction and speed.
S The lean of the tree. The lean of a tree

might not be apparent due to uneven or
slopingterrain. Use aplumborlevel to de­termine the direction of tree lean.

S Weight and branches on one side.
S Surrounding trees and obstacles.

Look for decay and rot. Ifthetrunk is rotted,
it can snap and fall toward the operator.
Make sure there is enough room for the tree to
fall. Maintain a distance of
from the nearest person or other objects. En­gine noise can drown out a warning call.
Remove dirt, stones, loose bark, nails, staples,
and wire from the tree where cuts are to be
made.

Plan a clear retreat path

45_

2-1/2 tree lengths

Direction of Fall

FELLING LARGE TREES

(15cmindiameterorlarger)

The notch method is used to fell large trees.
Anotchis cut on thesideofthe tree in thede­sired direction of fall. After a felling cut is
made on the opposite side of tree, the tree
will tend to fall into the notch.

NOTCH CUT AND FELLING THE
TREE

S Make notch cut by cutting the top of the

notch first. Cut through
ofthe tree. Nextcomplete thenotchbycut­ting the bottom of the notch. See illustra­tion. Once the notch is cut remove the
notch of wood from the tree.

Final cut here. 5 cm above

First cut

Notch

Second cut

S After removing the wood from the notch,

make the felling cut on the opposite side of
thenotch. This is done by makinga cut about
5 cm higher than the center of the notch.
This will leave enough uncut wood between
the felling cut and the notch to form a hinge.
This hinge will help prevent the tree from fall­ing in the wrong direction.

center of notch.

1/3 of the diameter

5cm

5cm

Hinge holds tree on stump and helps
control fall

Closing
of notch

NOTE: Before felling cut is complete, use

wedges to open the cut when necessary to
controlthedirectionoffall. Toavoidkickback
or chain damag e, use wood or plastic
wedges, but never steel or iron wedges.
S Bealerttosignsthatthetreeisreadytofall:

cracking sounds, widening of the felling cut,
or movement in the upper branches.

S As tree starts to fall, stop saw, put it down,

and get away quickly on your planned re­treat path.

S DO NOT cut down a partially fallen tree with

your saw. Be extremely cautious with par­tially fallen trees that may be poorly sup­ported. When a tree doesn’t fall completely,
set the saw aside andpull down the tree with
a cable winch, block and tackle, or tractor.

Opening
of felling
cut

CUTTING A FALLEN TREE

(BUCKING)

Bucking is the term used for cutting a fallen
tree to the desired log length.

WARNING: Do not stand on the log

being cut. Any portion can roll causing loss
of footing and control. Do not stand downhill
of the log being cut.

Important points

S Cut only one log at a time.
S Cut shattered wood very carefully; sharp

piecesofwood could beflungtowardoper­ator.

S Use a sawhorse to cut small logs. Never

allow another person to hold the log while
cuttingandnever holdthelogwithyour leg
or foot.

S Do not cut in an area where logs, limbs,

and roots are tangled. Drag the logs into a
clear area before cutting by pulling out ex­posed and cleared logs first.

TYPES OF CUTTING USED FOR
BUCKING

WARNING: If saw becomes pinched

or hung in a log, don’t try to force it out. You
can lose control of the saw resulting in injury
and/or damage to the saw. Stop the saw,
drive a wedge of plastic or wood into the cut
untilthesawcan beremovedeasily. Restart
thesaw andcarefully reenter the cut. Do not
attemptto restart your saw whenitispinched
or hung in a log.

Turn saw OFF and use a plastic or
wooden wedge to force cut open.

11

Overcutting begins on thetop side of thelog
with the saw against the log. When overcut­ting use light downward pressure.

Overcutting

Using a support stand

nd

2

Cut

Undercutting

Undercuttinginvolves cuttingon theunder­sideofthelog with top of saw againstthelog.
When undercutting use light upward pres­sure. Hold saw firmly and maintain control.
The saw will tend to push back toward you.

WARNING: Never turn saw upside

down to undercut. The saw cannot be con­trolled in this position.

First cut on pressure side of log

Second cut

Second cut

First cut on pressure side of log

BUCKING WITHOUT A
SUPPORT

S Overcut through 1/3 of the diameter of the

log.

S Roll the log over and finish with a second

overcut.

S Give special attention to logs under strain

to prevent the saw from pinching. Make
the first cut onthe pressure side to relieve
the stress on the log.

BUCKING USING A LOG OR SUP­PORT STAND

S Remember your first cut is always on the

pressure side of the log.

S Your first cut should extend

diameter of the log.

S Finish with your second cut.

Usingalogforsupport

2ndCut

2

st

1

nd

1/3 of the

Cut

1stCut

Cut

1stCut

1stCut

nd

2

Cut

LIMBING AND PRUNING

WARNING: Be alert for and guard

against kickback. Do not allow the moving
chain to contact any other branched or objects
at the nose of the guide bar when limbing or
pruning. Allowing such contact can result in
serious injury.

WARNING: Neverclimbintoatreeto

limb or prune. Do not stand on ladders, plat­forms, a log, or in any position whichcan cause
you to lose your balance or control of the saw.

IMPORTANT POINTS

S Watch out for springpoles. Use extreme

caution when cutting small size limbs. Slen­der material may catch the saw chain andbe
whipped toward you or pull you off balance.

S Be alert for springback. Watch out for

branches that are bent or under pressure.
Avoid being struck by the branch or the
saw when the tension in the wood fibers is
released.

S Keep a clear work area. Frequently clear

branches out of the way to avoid tripping
over them.

LIMBING

S Alwayslimbatreeafter it is cut down. Only

then can limbing be done safely and prop­erly.

S Leave the larger limbs underneath the

felled tree to support the tree as you work.

S Startat base of the felledtreeand work to-

ward the top, cutting branches and limbs.
Remove small limbs with one cut.

S Keep the tree between you and the chain

as much as possible.

S Remove larger, supporting branches with

thecuttingtechniques describedinBUCK­ING WITHOUT A SUPPORT.

S Always use an overcut to cut small and

freely hanging limbs. Undercutting could
cause limbs to fall and pinch saw.

PRUNING

WARNING: Limit pruning to limbs

shoulder height or below. Do not cut if
branches are higher than your shoulder.Get
a professional to do the job.

12

S Make your fist cut 1/3 of the way through

the bottom of the limb.

S Nextmakea 2ndcut all the way through

the limb. Then cut a third overcut leaving

a3 to5 cm collar fromthe trunkof the tree.

SERVICE AND ADJUSTMENTS

Third cut

Collar

Second cut

First cut

Pruning technique

WARNING: Improper maintenance

could result in serious engine damage or in se­rious injury.

WARNING: Disconnect the spark

plugbeforeperforming maintenance, except
for carburetor adjustments.

We recommend allservice and adjustments
not listed in this manual be performed by an
Authorized Service Dealer.

MAINTE NANCE SCHEDULE

Check:

Fuel mixture level Before each use....

Bar lubrication Before each use.......

Chain tension Before each use.......

Chain sharpness Before each use....

For damaged parts Before each use..

For loose caps Before each use......

For loose fasteners Before each use...

For loose parts Before each use......

Inspect and Clean:

Bar Before each use................

Complete saw After each use.......

Air filter Every 5 hours*.............

Chain brake Every 5 hours*........

Spark arresting screen

and muffler Every 25 hours*.........

Replace spark plug Ye a r ly.
Replace fuel filter Ye a rly...

*HoursofOperation

AIR FILTER

CAUTION: Do not clean filter in gaso-

line or other flammable solvent to avoid
creating a fire hazard or producing harmful
evaporative emissions.

Cleaning the air filter:

A dirty air filter decreases engine perform­ance and increases fuel consumption and
harmful emissions. Always clean after every
5 hours of operation.

1. Clean the cover andthe area around it to
keep dirt and sawdust from falling into
the carburetor chamber when the cover
is removed.

2. Remove the parts as illustrated.

3. Wash the filter in soap and water. Rinse
in clean cool water. Air dry completely
before reinstalling.

4. Reinstall parts.

Air Filter

Cover

Air Filter

BAR MAINTENANCE

If your saw cuts to one side, has to be forced
throughthecut,orbeenrunwithanimproper
amount of bar lubrication it may be neces­sary toservice yourbar. Awornbar will dam­age your chain and make cutting difficult.
After each use, ensure ON/STOP switch is
in the STOP position, then clean all sawdust
from the guide bar and sprocket hole.
To maintain guide bar:
S Move ON/STOP switch to the STOP posi-

tion.

S Loosen and remove bar nuts and chain

brake. Remove bar and chain from saw.

S Cleanthe oil holes and bar groove aftereach

5 hours of operation.

Remove Sawdust From

Guide Bar Groove

Oil Holes

S Burring of guide bar rails is a normal

process of rail wear. Remove these burrs
with a flat file.

S Whenrail top is uneven, use a flat file to re-

store square edges and sides.

Replace guide bar when the groove is worn,
the guide bar is bent or cracked, or when

File Rail Edges

and Sides

Square

Cylinder
Cover

Correct GrooveWorn Groove

13

excess heating or burring of the rails occurs.

A

v

If replacement is necessary, use only the guide
barspecifiedfor your saw in the repair parts list
or on the decal located on the chain saw.

SPARKPLUG

The spark plug should be replaced each
year to ensure the engine starts easier and
runs better. Ignition timing is fixed and non­adjustable.

1. Loosen 3 screws on cylinder cover.

2. Remove the cylinder cover.

3. Pull off the spark plug boot.

4. Remove spark plug from cylinder and
discard.

5. Replace with Champion RCJ--7Y spark
plug and tighten securely with a 19 mm
socket wrench. Spark plug gap should
be 0,5 mm.

6. Reinstall the spark plug boot.

7. Reinstall the cylinder cover and 3
screws. Tighten securely.

Cylinder

Cover

2. Check chain for proper tension. Adjust
chain tension if necessary.

3. Sharpen cutters.

S To sharpen the cutters, position the

file holder level (90˚) so that it rests
on the top edges of the cutter and
depth gauge.

NOTE: The chain has both left and

right hand cutters.

File Holder

Cutter

S Align the 30˚ fileholder marks paral-

File

90˚

Depth Gauge

lelwith thebarandto thecenter ofthe
chain.

Cutter

Spark

Plug Boot

Spark

Plug

CHAIN SHARPENING

WARNING: Improper chain sharpen-

ing techniques and/or depth gauge mainte­nance will increase the chance of kickback
which can result in serious injury.

WARNING: Wear protective gloves

when handling chain. The chain is sharp and
can cut you even when it is not moving.
Conditions which indicate the need for chain
sharpening:
S Reduction in size of wood chips. The size

ofthewoodchipwilldecrease as thechain
gets duller until it becomes more like a
powder than a chip. Note that dead or
rotted wood will not produce a good chip.

S Saw cuts to one side or at an angle.
S Saw has to be forced through the cut.

Tools required:

S 5/32 inch (4 mm) diameter round file and

file holder

S Flat file
S Depth gauge tool

TO SHARPEN CHAIN:

1. MoveON/STOPswitchtotheSTOP
position.

30˚
File Holder Line

S Sharpen cutters on one side of the

chain first. File from the inside of each
cutter to the outside. Then, turn the
chain saw around and repeat the pro­cess for the other side of the chain.

S File on theforward stroke only.Use 2

or 3 strokes per cutting edge.

S Keep all cutters the same length

when filing.

S File enough to remove any damage

to cutting edges (side plate and top
plate of cutter).

ll Cutters

Same Length

S File chain to meet the specifications

as shown.

30˚

Hook Angle

Cutter

Right

Remo

Top Plate

80˚

0,65 mm

Rounded
Corner

e Damage

Side Plate

60˚

14

f

f

Too Much HookAngle

Wrong

WARNING: Maintain the proper hook

angle according to the manufacturer’s specifi­cations for the chain you are using. Improper
hook angle will increase the chance of kick­back which can result in serious injury.

4. Check and lower depth gauges.

Depth Gauge Tool

S Place gauge tool on cutter.
S If the depth gauge is higher than the

depthgaugetool,fileitleveltothe top of
the depth gauge tool.

S Maintain rounded front corner of

depth gauge with a flat file.

NOTE: The very top of the depth

gauge should be flat with the front

half rounded off with a flat file.
If you require further assistance or are unsure
about performing this procedure, contact your
authorized service dealer.

Squared O
Corner

File

Depth Gauge

CARBURETOR ADJUSTMENT

WARNING: The chain will be moving

during most of this procedure. Wear your pro­tective equipment and observe all safety pre­cautions. The chain must not move at idle
speed.
The carburetor has been carefully set at the
factory. Adjustments may be necessary if
you notice any of the following conditions:
S Chain moves at idle. See IDLE SPEED--T

adjusting procedure.

S Sawwill not idle. See IDLESPEED--T ad-

justing procedure.

Idle Speed-- T

Allow engine to idle. If the chain moves, idle
istoo fast. If the enginestalls, idleis tooslow.
Adjust speed until engine runs without chain
movement (idle too fast) or stalling (idle too
slow). The idle speed screw is located inthe
area above the primer bulb and is labeled T.

S Turnidle speed screw (T) clockwise to in-

crease engine speed.

S Turn idle speed screw (T) counterclock-

wise to decrease engine speed.

STORAGE

WARNING: Stop engine and allow to

cool, and secure the unit before storing or
transporting in a vehicle. Store unit and fuel
in an area where fuel vapors cannot reach
sparks or open flames from water heaters,
electric motors or switches, furnaces, etc.
Storeunit withallguards in place. Positionso
that any sharp object cannot accidentally
cause injury to passersby. Store the unit out
of reach of children.
S Before storing, drain all fuel from the unit.

Start engine and allow to run until it stops.

S Clean the unit before storing. Pay particu-

lar attention to the air intake area, keeping
it free of debris. Use a mild detergent and
sponge to clean the plastic surfaces.

S Donotstore theunit or fuel ina closedarea

where fuel vapors can reach sparks or an
openflamefromhotwater heaters,electric
motors or switches, furnaces, etc.

S Store in a dry area out of the reach of chil-

dren.

S Ensure the machine is cleaned and that a

complete service is carried out before
long--term storage.

S The guide bar and chain must always be

covered with a scabbard when the machine
is being transported or in storage in order to
prevent accident contact with the sharp
chain. Even a non--moving chain can cause
serious cuts to yourself or persons you
bump into with an exposed chain.

CAUTION: It is important to prevent

gum deposits from forming in essential fuel
system parts such as the carburetor, fuel fil­ter,fuel hose, or fuel tank during storage. Al­cohol blended fuels (called gasohol or using
ethanol or methanol) can attract moisture
which leads to fuel mixture separation and
formationofacids during storage. Acidic gas
can damage the engine.

15

TROUBLESHOOTING TABLE

WARNING: Always stop unit and disconnect spark plug before performing all of

therecommendedremediesbelow exceptremedies that require operation of the unit.

TROUBLE CAU SE REMEDY

Engine will not
start or will run
only a few
seconds after
starting.

Engine will
not idle
properly.

Engine will not
accelerate,
lacks power,
or dies under
a load.

Engine
smokes
excessively.

Chain moves
at idle speed.

1. Ignition switch off.

2. Engine flooded.

3. Fuel tank empty.

4. Spark plug not firing.

5. Fuel not reaching
carburetor.

1. Idle speed requires
adjustment.

2. Carburetor requires

adjustment.

1. Air filter dirty.

2. Spark plug fouled.

3. Chain brake engaged.

4. Carburetor requires

adjustment.

1. Toomuch oil mixed with
gasoline.

1. Idle speed requires
adjustment.

2. Clutch requires repair.

1. Move ignition switch to ON.

2. See “Difficult Starting” in
Operation Section.

3. Fill tank with correct fuel mixture.

4. Install new spark plug.

5. Check for dirty fuel filter; replace.
Check for kinked or split fuel line;
repair or replace.

1. See “Carburetor Adjustment” in the
Service and Adjustments Section.

2. Contact an authorized service dealer.

1. Clean or replace air filter.

2. Clean or replace plug and regap.

3. Disengage chain brake.

4. Contact an authorized service dealer.

1. Empty fuel tank and refill with
correct fuel mixture.

1. See “Carburetor Adjustment” in the
Service and Adjustments Section.

2. Contact an authorized service dealer.

DECLARATION OF CONFORMITY

EC Declaration of Conformity (Only applies to Europe)
We, Husqvarna AB, SE--561 82 Huskvarna, Sweden, Tel: [phone], as authorised

representative in the Community, declare that the chain saw models McCulloch Mac 738,
Mac 740, and Mac 742 SAS-AV from serial numbers 2009--031(N or D)00001 and onwards
(the year is clearly stated on the rating plate, followed by the serial number), comply with the
requirements of the COUNCIL’S DIRECTIVES:

of 22 June 1998 “relating to machinery” 98/37/EC, annex IIA;
of 15 December 2004“relating to electromagnetic compatibility” 2004/108/EC, andapplicable

supplements; and
of 8 May 2000 “relating to the noise emissions in the environment” in accordance with Annex

Vof2000/14/EC. Themeasured sound power is 108,7 dB(A), the guaranteedsound power is
113 dB(A) and the net power is 1,5 kW or 1,6 kW.

The following standards have been applied: ISO 11681--1:2004, EN/ISO 12100--1:2003,

EN/ISO 12100--2:2003, and CISPR 12:2001.
Notified body,0404 the Swedish Machinery Testing Institute, Fyrisborgsgatan 3 S--75450

Uppsala, Sweden, has carried out EC type approval. The certificate(s) is numbered:
404/05/1079.

The supplied Chain Saw conforms with the sample that underwent the EC type approval.

09--1--31

Ronnie E. Goldman, Director of Engineering
Handheld Consumer Products

16

TECHNICAL DATA SHEET

Engine Mac 738 740 742

Cylinder volume, cm
Stroke, mm 32 32 32
Idle speed, rpm 3000 3000 3000
Recommended max.
speed, unloaded, rpm 12000 12000 12000
Power, kW 1,5 1,5 1,6

Ignition system

Manufacturer W albro
Type of ignition system Inductive
Spark plug Champion
Electrode gap, mm 0,5

Fuel and lubrication system

Manufacturer Zama
Carburetor type W-26B
Fuel capacity, litre 0,34
Oil pump capacity at
8500 rpm, ml/min 4 -- 8
Oil capacity, litre 0,2
Type of oil pump Automatic

Weight

Without bar and chain, kg 5,5

Length Pitch Max
Inches Inches Tip Radius

14 0,375 7T Oregon 91VJ
14 0,375 7T Oregon 91VG
16 0,375 7T Oregon 91VJ
16 0,375 7T Oregon 91VG

3

38 40 42

BAR CHAIN

Noise levels Mac738/740/742

Equivalent (see note 1) noise
pressure level at operator’s ear,
measured according to relevant
international standards, dB(A) 99,7
Equivalent (see note 1) noise
power level, measured
according to relevant
international standards, dB(A) 108,7

Vibration levels

(see note 2)
Front handle, m/s
Rear handle, m/s

2

2

5,4
5,4

Chain/bar

Standard bar length, in/cm 14/35 16/40
Recommended bar lengths,
in/cm 14/35 16/40
Usable cuttinglength, in/cm 13,5/34 15,5/39
Chain speed at maximum
power, m/sec 18,5
Pitch, inches 0,375
Thickness of drive link, mm 1,3
No. of teeth on drive sprocket 6

Note1: Equivalent noise level is, according to
ISO 22868, calculated as the time--weighted
energy total for noise levels under various
working conditions with the following time dis­tribution, 1/3 idle, 1/3 full load, 1/3 full speed.

Note2: Equivalent vibrationlevel is, according
toISO22867,calculated as the time--weighted
energy total for vibration levels under various
working conditions with the following time dis­tribution: 1/3 idle, 1/3 full load, 1/3 full speed.

91VJ

91VG

0,375

0,375

0,050/1,3 5/32 / 4,0 0,025/0,65

0,050/1,3

5/32 / 4,0

80° 30°

80°

30°

0°

0° 0,025/0,65

17

in/cm :dl

14/35:52
16/40:56

14/35:52
16/40:56