Husqvarna 125 L Service Manual

							11
KNOW YOUR TRIMMER
1. Trimmer head 11. Starter handle
2. Grease filler cap 12. Fuel tank
3. Bevel gear 13. Choke control
4. Cutting attachment guard 14. Air purge
5. Shaft 15. Air filter cover
6. Loop handle 16. Handle adjustment
7. Throttle control 17. Drive disc
8. Stop switch 18. 2-- stroke engine oil
9. Throttle lock 19. Operator’s manual (EPA)
10. Cylinder coverKNOW YOUR TRIMMER
5
2
910
6
16
17
1
4
18
13
811
15
1314
7
12
19
125C 125L
1
4 
						

							12
ASSEMBLY
Fitting the trimmer guard and
trimmer head (Model 125L)
SFit the correct trimmer guard (A) for use
with the trimmer head. Hook the trimmer
guard/combination guard onto the fitting
on the shaft and secure with the bolt (D).
Make sure unit is assembled
correctly as shown in this
manual.
Fitting the loop handle
SPosition the handle on the shaft. Note
that the handle must be mounted be-
tween the two arrows on the shaft.
SFit the screw, securing plate and wing
nut as shown in the diagram.
STighten the wing nut.
ADAB
C
SFit the drive disc (B) on the output shaft.
STurn the shaft until one of the holes in the
drive disc aligns with the corresponding
hole in the gear housing.
SInsert hex wrench (C) in the hole to lock
the shaft.
SScrew on the trimmer head (H) in the op-
posite direction to the direction of rota-
tion.
H
STo dismantle, follow the instructions in
the reverse order.
Fitting the trimmer guard and
trimmer head (Model 125C)
SFit the correct trimmer guard (A) for use
with the trimmer head. Hook the trimmer
guard/combination guard onto the fitting on
the shaft and secure with the wing nut (B).
A
CB
SFit the dust cup (C) on the shaft. The nut
must be completely covered by the dust
cup.
SHold the dust cup with a wrench to pre-
vent the shaft from rotating.
SScrew the trimmer head (D) onto the
shaft.
STo dismantle, follow the instructions in
the reverse order.
D 
						

							13
FUEL HANDLING
FuelCAUTION!The machine is equipped with
a two-- stroke engine and must always be
run using a mixture of gasoline and two--
stroke engine oil. It is important to accu-
rately 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 drastical-
ly affect the ratio of the mixture.
Gasoline
CAUTION!Always use high quality
unleaded gasoline.
SThis engine is certified to operate on
unleaded gasoline.
SThe lowest recommended octane rating
is 87. If you run the engine on lower oc-
tane rating than 87, “knocking” can oc-
cur. This leads to an increased engine
temperature, which can result in a seri-
ous engine breakdown.
SWhen working at continuous high revs a
higher octane rating is recommended.
Tw o -- s t r o k e o i lSFor great results and performance use
HUSQVARNA two-- stroke oil, which is
specially formulated for our two-- stroke
engines. Mixture 1:50 (2%).
STo maximize the life of your trimmer, you
may choose to use a high quality syn-
thetic oil formulated for two-- stroke
engines. Mixture 1:50 (2%).
SNever use two-- stroke oil intended for
water-- cooled outboard engines,
sometimes referred to as outboard oil.
SNever use oil intended for four-- stroke
engines.
WARNING!Always ensure
there is adequate ventilation when
handling fuel.
U.S. gallon U.S. fl. oz.
121/2
2 1/2 6 1/2
5127/8GasolineTw o -- s t r o k e o i l
2% (1:50)S
Always start byflling halfthe amount ofthe gasoline to be used. Then add the
entire amount of oil. Mix (shake) the
fuel mixture. Add the remaining amount
of gasoline.
SMix (shake) the fuel mixture thoroughly
before filling the machine’s fuel tank.
SDo not mix more than one month’s sup-
ply of fuel at a time.
SIf the machine is not used for some time,
the fuel tank should be emptied and
cleaned.
WARNING!The catalytic con-
verter muffler gets very hot during
and after use. This also applies
during idling. Be aware of the fire
hazard, especially when working
near flammable substances and/or
vapors.
Fueling
WARNING!Taking the following
precautions, will lessen the risk of
fire:
Do not smoke or place hot objects
near fuel.
Always shut off the engine before
refueling.
Always stop the engine and let it
cool for a few minutes before refu-
elling.
When refueling, open the fuel cap
slowly so that any excess pressure
is released gently.
Tighten the fuel cap carefully after
refueling.
Always move the machine away
from the refueling area before
starting.
Min. 10 ft.
(3 m)MixingSAlways mix the gasoline and oil in a
clean container intended for fuel. 
						

							14
STARTING AND STOPPING
Check before starting
SInspect the unit before each use. Re-
place damaged parts. Check for fuel
leaks. Make sure all fasteners are in
place and secure. Make sure the cutting
attachment is properly installed and se-
curely fastened. Use only flexible, non-
metallic line recommended by the
manufacturer. Never use, for example,
wire or wire rope, which can break off
and become a dangerous projectile.
SCheck that the trimmer head and trimmer
guard are not damaged or cracked.
Replace the trimmer head or trimmer
guard if they have been exposed to
impact or are cracked.
SNever use the machine without a guard
nor with a defective guard.
Starting and stopping
WARNING!The complete clutch,
clutch cover, and shaft must be
fitted before the machine is started,
otherwise parts could come loose
and cause personal injury.
Always move the machine away
from the refueling area before
starting. Place the machine on a
flat surface. Ensure the cutting at-
tachment cannot come into contact
with any object.
Make sure no unauthorized persons
are in the working area, otherwise
there is a risk of serious personal
injury. The safety distance is 50 feet
(15 meters).
Cold engineAir purge:Press the air purge diaphragm
6 -- 10 times until fuel begins to fill the dia-
phragm. The diaphragm need not be com-
pletely filled.
Choke:Move the blue engine choke lever
over to the closed position.
SClean the area around thefuel cap. Con-
tamination in the tank can cause operat-
ing problems.
SEnsure that the fuel is well mixed by
shaking the container before filling the
tank.
StartingHold the body of the machine on the
ground using your left hand (CAUTION!
Not with your foot!).
Grip the starter handle. Slowly pull out the
cord with your right hand until you feel
some resistance (the starter pawls grip);
then quickly and powerfully pull the cord.
Never wrap the starter cord around
your hand.
Repeat pulling the cord until the engine
attempts to start. Squeeze throttle trigger
to release the choke and pull starter rope
until engine runs.
NOTE:If engine dies, return blue engine
choke lever to the closed position and
repeat starting steps.
CAUTION!Do not pull the starter cord all
the way out and do not let go of the starter
handle when the cord is fully extended.
This can damage the machine. 
						

							15
STARTING AND STOPPING
Warm en gi n eWith a warm engine, squeeze and hold the
throttle trigger. Pull starter rope sharply
while squeezing throttle trigger until engine
runs.
StoppingStop the engine by pushing and holding
the stop switch in the STOP position until
the engine stops.
WARNING!Whentheengineis
started with the choke in the closed
position the cutting attachment will
start to rotate immediately. 
						

							16
MAINTENANCE
The idle speed is correctly adjusted when
the engine will run smoothly in every posi-
tion. The idle speed should also be well
below the speed at which the cutting at-
tachment starts to rotate.
CarburetorYour Husqvarna product has been designed
and manufactured to specifications that re-
duce harmful emissions. After the engine
has used 8-- 10 tanks of fuel, the engine will
be run-- in. To ensure that it continues to run
at peak performance and to minimize harm-
ful exhaust emissions after the run-- in peri-
od, ask your servicing dealer to adjust your
carburetor.The owner is responsible
for the perfor-
mance of all required maintenance as
defined in the operator’s manual.
WARNING!The complete clutch,
clutch cover, and shaft must be
fitted before the machine is started,
otherwise parts could come loose
and cause personal injury.
Function
SThe carburetor governs the engine’s
speed via the throttle control. Air and fuel
are mixed in the carburetor.
SThe T-- screw regulates the throttle setting
at idle speed. If the T-- screw is turned
clockwise this gives a higher idle speed;
turning it counterclockwise gives a lower
idle speed.
Basic settingSThe basic carburetor settings are ad-
justed during testing at the factory. Fine
adjustment should be carried out by a
skilled technician.
CAUTION!If the cutting attachment rotates
when the engine is idling the idle adjustment
screw T should be turned counterclockwise
until the cutting attachment stops.
Rec. idle speed:
See “Technical data” section.
Recommended max. speed:
See “Technical data” section.
Fine adjustment of the idle
speed -- T
Adjust the idle speed using the idle adjust-
ment screw-- T if it is necessary to readjust.
First, turn the idle adjustment screw-- T
clockwise until the cutting attachment starts
to rotate. Then, turn the screw counterc-
lockwise until the cutting attachment stops.
WARNING!Iftheidlespeed
cannot be adjusted so that the cut -
ting attachment stops, contact your
dealer/service workshop. Do not use
the machine until it has been cor -
rectly adjusted or repaired.
Idle Speed
Screw-- T
WARNING!If the idle speed can -
not be adjusted so that the cutting
attachment stops, contact your ser -
vicing dealer. Do not use the ma -
chine until it has been correctly ad -
justed or repaired.
Unit/Maintenance SafetyDisconnect the spark plug before perform-
ing maintenance, except carburetor adjust-
ments.
Muffler
CAUTION!Muffler is fitted with a catalytic
converter designed to reduce harmful ex-
haust gases.
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 com-
bustible material.
Mufflers are equipped with a special spark
arrestor mesh. The mesh should be
checked and, if necessary. cleaned by a
servicing dealer.If the mesh is damaged,
it should be replaced.Ifthemeshisfre-
quently blocked, this can be a sign that the
performance of the catalytic converter is
impaired. Contact your servicing dealer to
inspect the muffler. A blocked mesh will
cause the machine to overheat and result
in damage to the cylinder and piston. 
						

							17
MAINTENANCE
Air filter
The air filter must be regularly cleaned to
remove dust and dirt in order to avoid:
SCarburetor malfunctions
SStarting problems
SLoss of engine power
SUnnecessary wear to engine parts
SExcessive fuel consumption
Clean the filter every 25 hours, or more
regularly if conditions are exceptionally
dusty.
Cleaning the air filterRemove the air filter cover and take out the
filter. Wash it clean in warm, soapy water.
Rinse thoroughly. Ensure that the filter is dry
before refitting it.
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.
Bevel gear
(125L)
The bevel gear is filled with the right quan-
tity of grease at the factory. However, be-
fore using the machine you should check
that the bevel gear is filled three-- quarters
full with grease. Use HUSQVARNA special
grease.
Spark plug
The spark plug condition is influenced by:
SIncorrect carburetor adjustment.
SAn incorrect fuel mixture (too much or in-
correct type of oil).
SA dirty air filter.
These factors cause deposits on the spark
plug electrodes, which may result in operat-
ing 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
0.024″(0.6 mm). The spark plug should be
replaced after about a month in operation or
earlier if necessary.0.024″(0.6 mm)
Muffler bolts
CAUTION!Never use a machine that has
a faulty or loose muffler. Ensure the muffler
bolts are tight.
WARNING!Mufflers fitted with
catalytic converters get very hot
during use and remain so for some
time after stopping. This also ap -
plies at idle speed. Contact can re -
sult in burns to the skin. Remember
theriskoffire!
WARNING!The inside of the
muffler contain chemicals that may
be carcinogenic. Avoid contact with
these elements in the event of a
damaged muffler.
WARNING!Bear in mind that:
Engine exhaust fumes contain car -
bon monoxide, which can cause
carbon monoxide poisoning. For
this reason you should not start or
run the machine indoors, or any -
where that is poorly ventilated.
The exhaust fumes from the engine
are hot and may contain sparks
which can start a fire. Never start
the machine indoors or near com -
bustible material!
CAUTION!Always use the recommended
spark plug type! Use of the wrong spark
plug can damage the piston/cylinder. 
						

							18
MAINTENANCE
Maintenance scheduleBelow you will find some general mainte-
nance instructions.
Daily maintenanceSCheck throttle trigger and throttle trigger
lockout function.
SCheckthatthestopswitchworks
correctly.
SCheck that there are no fuel leaks from
the engine, tank or fuel lines.
SCheck that the cutter does not rotate
when the engine is idling.
SClean the outside of the machine.
SCheck that the harness is not damaged.
SCheck that the blade guard is not dam-
aged or cracked.
SReplace the blade guard if it is exposed to
impact or is cracked.
SA non-- balanced trimmer head induces
heavy vibrations that may damage the
machine.
SCheck that nuts and screws are tight.
SCheck that the screws that hold the bevel
gear are tight.
SCheck that the trimmer head is tight.
Weekly maintenanceSCheck the starter and starter cord.
SClean the carburetor area.
SClean the outside of the spark plug. Re-
move it and check the electrode gap. Ad-
just the gap to 0.024″(0.6 mm), or
replace the spark plug. Use resistor spark
plug Champion RCJ -- 6Y or equivalent.
SClean the cooling fins on the cylinder and
check that the air intake near the starter
is not blocked.
SCheck that the bevel gear is filled with
grease up to 3/4 full. Use special grease.
SClean the air filter.
Monthly maintenanceSClean the fuel tank.
SClean the outside of the carburetor and
the space around it.
SClean the fan and the area around it.
SCheck fuel lines for cracks or other dam-
age. Change if necessary.
SChange the fuel filter in fuel tank.
SCheck the clutch, clutch springs and the
clutch drum for wear. Replace if neces-
sary.
SCheck electrical wires and connections.
SReplace the spark plug. Use resistor
spark plug Champion RCJ -- 6Y or equiva-
lent.
SChange the air filter.
The grease in the bevel gear does not nor-
mally need to be changed except if repairs
are carried out. 
						

							19
Trimmer Head Line Loading Instructions
20i
10i 3m 6m 
						

							20
TECHNICAL DATA
Model 125L(M10 LH arbor shaft thread)
Approved accessories Type Cutting attachment guard, part. no.
Trimmer head T25 537 33 83-- 02
Plastic blades Tricut 300 mm 531 00 38-- 24
J -- Handle kit (to equip
unit for brush blade) 503 78 17-- 01
*Brush blade 537 14 95-- 01
Technical data125C 125L
Engine
Cylinder volume, cu.in./cm
31.7/28 1.7/28
Cylinder bore, inch/mm 1.4/35 1.4/35
Stroke, inch/mm 1.130/28.7 1.130/28.7
Idle speed, rpm 2,800-- 3,200 2,800-- 3,200
Recommended max. speed, rpm 10,000 11,000
Speed of output shaft, rpm 8,000 8,000
Max. engine output, acc. to ISO 8893, hp/kW 1.1/0.8 1.1/0.8
Catalytic converter muffler Yes Yes
Speed-- regulated ignition system No No
Ignition system
Manufacturer/type of ignition system Walbro/CD Walbro/CD
Spark plug Champion Champion
RCJ-- 6Y RCJ-- 6Y
Electrode gap, inch/mm 0.024/0.6 0.024/0.6
Fuel and lubrication system
Manufacturer/type of carburetor Zama Zama
Fuel tank capacity, US pint/liter 0.85/0.4 0.85/0.4
Weight
Weight without fuel, cutting attachment and guard, lbs/kg 10/4.4 11/4.8
Sound levels
(see note 1)
Equivalent sound pressure level at the user’s ear,
measured according to ANSI B175.3-- 1997, dB(A),
min/max: 94/97 94/97
Vibration levels
Vibration levels at handles, measured according to ANSI
B175.3-- 1997, m/s
2
At idle, left/right handles: 3/5 3/5
At max. speed, left/right handles: 9/8 9/8
Note 1:Equivalent noise pressure level is calculated as the time-- weighted energy total for
noise pressure levels under various working conditions with the following time distribution:
1/2 idle and 1/2 max. speed.
NOTE!Noise pressure at the user’s ear and vibration on the handles are measured with all
the machine’s approved cutting equipment fitted. The table indicates the highest and lowest
values.
*For safety reasons, use ONLY when the trimmer has been fitted with the J -- handle kit!
Model 125C(3/8 RH arbor shaft thread)
Approved accessories Type Cutting attachment guard, part. no.
Trimmer head T25 537 33 83-- 03