Husqvarna 340i Instruction manual

Workshop manual
340i
English
1435 - 001 - 11.06.2020

Contents
1 Introduction
1.1 Document description............................................ 3
1.2 Target group...........................................................3
1.3 Revisions................................................................3
1.4 Safety..................................................................... 3
1.5 Servicing tools........................................................3
2 Safety
2.1 Safety definitions....................................................4
2.2 General safety instructions.....................................4
2.3 Symbols on the product......................................... 4
2.4 Special safety instructions......................................4
3 Servicing data
3.1 Servicing data (digital user interface).....................5
3.2 Servicing data (mechanical user interface)............ 7
4 Servicing tools
4.1 Servicing tools........................................................9
4.2 Electrical diagram.................................................10
5 Repair instructions
5.1 To clean and examine the product parts..............11
5.2 Drive sprocket and guide bar............................... 11
5.3 Chain tensioner ................................................... 13
5.4 Crankcase............................................................ 15
5.5 Power trigger........................................................16
5.6 Front handguard...................................................20
5.7 Motor and control unit.......................................... 20
5.8 User interface.......................................................23
5.9 Chain oil tank....................................................... 24
5.10 Chain brake........................................................24
5.11 Oil pump.............................................................26
6 Troubleshooting
6.1 Diagnostic tools....................................................27
6.2 Troubleshooting of the product............................ 28
6.3 Troubleshooting of the battery and battery
charger....................................................................... 30
7 Technical data
7.1 Technical data......................................................32
21435 - 001 - 11.06.2020

1 Introduction
1.1 Document description
This manual gives a full description of how to do
maintenance and repair on the product. It also gives
safety instructions that the personnel must obey.
1.2 Target group
This manual is for personnel with a general knowledge
of how to do repair and do servicing. All personnel that
do repair or do servicing on the product must read and
understand the manual.
1.3 Revisions
Changes to the product can cause changes to the
maintenance work and spare parts. Separate
information is sent out for each change.
Read the manual together with all received information
about changes to maintenance and spare parts for the
product.
1.4 Safety
WARNING: All personnel that repair or do
servicing on the product must read and
understand the safety instructions in this
workshop manual.
1.5 Servicing tools
The manual gives information about necessary servicing
tools. Always use original tools from Husqvarna.
1435 - 001 - 11.06.2020 Introduction - 3

2 Safety
2.1 Safety definitions
Warnings, cautions and notes are used to point out
specially important parts of the manual.
WARNING: Used if there is a risk of injury or
death for the operator or bystanders if the
instructions in the manual are not obeyed.
CAUTION: Used if there is a risk of damage to
the product, other materials or the adjacent area
if the instructions in the manual are not obeyed.
Note: Used to give more information that is necessary in
a given situation.
2.2 General safety instructions
WARNING: Apply a new warning label if a
warning symbol on the product is damaged or
missing.
2.3 Symbols on the product
Fill with chain oil
Start/Stop
savE / Battery save mode
Warning lamp/Fault indicator
Indication of chain direction
Chain brake
2.4 Special safety instructions
2.4.1 To remove the battery
WARNING: Always remove the battery before
you do repairs or do servicing on the product.
WARNING: Do not put the battery back until the
product is assembled.
1. Press in the catches and remove the battery.
2.4.2 Cutting equipment safety
WARNING: Always remove the cutting
equipment before you do repairs or do servicing
on the product.
WARNING: Do not install the cutting equipment
until the product is assembled.
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3 Servicing data
3.1 Servicing data (digital user interface)
▲ Lubricate with chain oil.
● Lubricate with grease.
1 - 2 Nm T20
1 - 2 Nm T20
7 - 8 Nm T27
(x3) 3.5 Nm T27
(x2) 1.8 - 2.2 Nm T27
(x5) 2.2 Nm T27
2.5 - 3 Nm T27
(x4) 1 - 2 Nm T20
3 Nm T27
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(x1) 4 Nm T27
(x2) 4 Nm T27
(x9) 2.5 - 3 Nm T27
(x4) 3 - 4 Nm T27
6 - Servicing data 1435 - 001 - 11.06.2020

3.2 Servicing data (mechanical user interface)
▲ Lubricate with chain oil.
● Lubricate with grease.
7 - 8 Nm T27
(x3) 3.5 Nm T27
(x2) 1.8 - 2.2 Nm T27
(x5) 2.2 Nm T27
2.5 - 3 Nm T27
(x4) 1 - 2 Nm T20
3 Nm T27
1 - 2 Nm T20
1 - 2 Nm T20
1435 - 001 - 11.06.2020 Servicing data - 7

(x1) 4 Nm T27
(x2) 4 Nm T27
(x9) 2.5 - 3 Nm T27
(x4) 3 - 4 Nm T27
8 - Servicing data 1435 - 001 - 11.06.2020

4 Servicing tools
4.1 Servicing tools
CST
INSTRUCTION
321
Posi-
tion
Description Use Article No.
1 Diagnostic tool kit To do a check of the product and install updates to the firm-
ware.
583 89 71-01
2 Adapter cable for battery
products
To do a check of battery products with the diagnostic tool kit. 581 19 23-01
3 T-handle Torx, T20 To loosen or remove Torx screws. 588 59 85-01
3 T-handle Torx, T27 To loosen or remove Torx screws. 502 71 27-03
1435 - 001 - 11.06.2020 Servicing tools - 9

4.2 Electrical diagram
1
4
7
3
6
9
2
5
8
Battery
White
Red
Blue
J8
J8
J7
J4
J3
J2
J5
J1
1
4
7
3
6
9
2
5
8
J10
J10
J12
Grey
2
J7
1
3
2
1
2
1
Yellow
Pink
1 1
2 2
Red
White
Black
Black
Grey
White
Blue Yellow Grey Green Black Orange Red
Pink
1 2 3 4 5 6 7 8 9
Trigger
White Blue Grey Green Black Orange Red
123 4 56789
1 2 3 4 5 6 7 8 9
White Black
1 2 3
Switch
Motor
10 - Servicing tools 1435 - 001 - 11.06.2020

5 Repair instructions
5.1 To clean and examine the product parts
• Clean and examine all parts fully. You find more
instructions in the chapter for each part if special
tools or procedures are necessary.
• Replace damaged or defective parts.
• Always use original spare parts.
5.2 Drive sprocket and guide bar
5.2.1 To remove and install a drive sprocket cover
attached with a bar knob
1. Loosen the bar knob.
2. Remove the drive sprocket cover.
3. Install in the opposite sequence.
5.2.2 To remove and install a drive sprocket cover
attached with a nut
1. Loosen the nut (A) and remove the drive sprocket
cover (B).
A
B
Note: The nut is attached to the drive sprocket
cover.
2. Install in the opposite sequence.
5.2.3 To remove and install the drive sprocket
1. Remove the drive sprocket cover. Refer to
To
remove and install a drive sprocket cover attached
with a bar knob on page 11 .
2. Remove the guide bar and the saw chain.
3. Hold the drive sprocket with adjustable pliers and
remove the screw (A).
C
D
B
A
4. Remove the small washer (B), the large washers (C)
and the drive sprocket (D).
5. Install in the opposite sequence.
CAUTION: The concave side of the large
washers must point in the direction of the
drive sprocket.
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5.2.4 To remove and install the brake drum
1. Remove the drive sprocket. Refer to
To remove and
install the drive sprocket on page 11 .
2. Move the front handguard rearward to release the
chain brake.
3. Remove the brake drum.
4. Examine the brake drum for damage. Replace the
brake drum if it is damaged.
5. Install in the opposite sequence.
5.2.5 To remove and install the worm gear
1. Remove the brake drum. Refer to To remove and
install the brake drum on page 12 .
2. Remove the worm gear.
3. Examine the worm gear for wear and damage.
Replace the worm gear if it is damaged.
4. Install in the opposite sequence. Make sure that the
flat surfaces in the worm gear are aligned with the
flat surfaces on the motor axle.
5.2.6 To remove and install the spiked bumper
1. Remove the drive sprocket cover. Refer to To
remove and install a drive sprocket cover attached
with a bar knob on page 11 .
2. Remove the guide bar and the saw chain.
3. Remove the 2 screws and the spiked bumper.
4. Examine the spiked bumper for wear and damage.
Replace the spiked bumper if it is damaged.
5. Install in the opposite sequence.
5.2.7 To remove and install the chain catcher
1. Remove the drive sprocket cover. Refer to To
remove and install a drive sprocket cover attached
with a bar knob on page 11 .
2. Remove the guide bar and the saw chain.
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3. Remove the screw and the chain catcher.
4. Examine the chain catcher for wear and damages.
Replace the chain catcher if it is worn or damaged.
5. Install in the opposite sequence.
5.3 Chain tensioner
5.3.1 Drive sprocket cover attached with a bar knob
5.3.1.1 To adjust the tension of the saw chain
WARNING: A saw chain with an incorrect
tension can come loose from the guide bar and
cause serious injury or death.
A saw chain becomes longer when you use it. Adjust the
saw chain regularly.
1. Loosen the bar knob that holds the drive sprocket
cover.
2. Lift the front of the guide bar and turn the chain
tensioning wheel. Tighten the saw chain until it is
tight against the guide bar.
3. Tighten the bar knob and lift the front of the guide
bar at the same time.
4. Make sure that you can pull the saw chain around
freely by hand and that it does not hang from the
guide bar.
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5.3.1.2 To disassemble and assemble the chain
tensioner
1. Remove the drive sprocket cover.
2. Remove the 2 screws and the chain tensioner cover.
3. Remove the collar (A), the chain tensioner (B) and
the shaft (C).
A
G
D
E
F
B
C
4. Remove the worm wheel gear (D), the washer (E),
the O-ring (F), and the chain tensioning knob (G).
5. Assemble in the opposite sequence.
5.3.2 Drive sprocket cover attached with a nut
5.3.2.1 To adjust the tension of the saw chain
WARNING: A saw chain with an incorrect
tension can come loose from the guide bar and
cause serious injury or death.
A saw chain becomes longer when you use it. Adjust the
saw chain regularly.
1. Loosen the bar nut that holds the drive sprocket
cover. Use the combination wrench.
2. Lift the front of the guide bar and turn the chain
tensioning screw. Use the combination wrench.
3. Tighten the saw chain until it is tight against the
guide bar.
4. Tighten the bar nut with the combination wrench and
lift the front of the guide bar at the same time.
5. Make sure that you can pull the saw chain around
freely by hand and that it does not hang from the
guide bar.
Note: Refer to Servicing data on page 5 for the position
of the chain tensioning screw on your product.
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5.3.2.2 To disassemble and assemble the chain
tensioner
1. Remove the drive sprocket cover. Refer to To adjust
the tension of the saw chain on page 14 .
2. Remove the 2 screws and the chain tensioner cover.
3. Remove the chain tensioner (A), shaft (B),
adjustment screw (C), washer (D) and O-ring (E)
from the drive sprocket cover.
A
B
C
D
E
4. Assemble in the opposite sequence.
5.4 Crankcase
5.4.1 To remove and install the front handle
1. Remove the 2 screws (A) on the side of the front
handle.
A
B
2. Remove the 2 screws (B) at the bottom of the front
handle and remove the front handle.
3. Install in the opposite sequence.
CAUTION: Make sure that the screws are in
the correct positions. If a long screw is
installed at the bottom of the product, the oil
tank can become damaged.
5.4.2 To remove and install the handle insert
1. Remove the screw on the rear handle and carefully
pull out the handle insert.
2. Install in the opposite sequence.
5.4.3 To disassemble and assemble the crankcase
1. Remove the handle insert. Refer to To remove and
install the handle insert on page 15 .
2. Move the front handguard rearward to release the
chain brake.
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3. Remove the 9 screws.
4. Remove the left crankcase half.
5. Assemble in the opposite sequence.
CAUTION: Make sure that all parts are
installed correctly in the crankcase to
prevent damage to the cables.
5.4.4 To replace the guide bar bolt
1. Remove the drive sprocket cover. Refer to To
remove and install a drive sprocket cover attached
with a bar knob on page 11 .
2. Remove the guide bar and the saw chain.
3. Disassemble the crankcase. Refer to To
disassemble and assemble the crankcase on page
15 .
4. Remove the chain brake wheel. Refer to To remove
and install the chain brake wheel on page 25 .
5. Remove the guide bar bolt and the plate.
6. Put the new guide bar bolt through the hole in the
crankcase.
7. Use a hammer and a mandrel to install the new
guide bar bolt.
8. Install the chain brake wheel. Refer to To remove
and install the chain brake wheel on page 25 .
9. Assemble the crankcase. Refer to To disassemble
and assemble the crankcase on page 15 .
10. Install the guide bar and the saw chain.
11. Install the drive sprocket cover. Refer to To remove
and install a drive sprocket cover attached with a bar
knob on page 11 .
5.5 Power trigger
5.5.1 To disassemble the power trigger (digital user
interface)
1. Disassemble the crankcase. Refer to
To
disassemble and assemble the crankcase on page
15 .
2. Make a note of how the inner parts of the power
trigger handle are installed.
3. Remove the power trigger lockout.
4. Make sure that the power trigger lockout has no
defects. Replace the power trigger lockout if it has
defects.
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5. Remove the power trigger.
6. Pull out the recoil spring from the power trigger.
7. Make sure that there is tension in the recoil spring.
Replace the recoil spring if it is necessary.
5.5.2 To assemble the power trigger (digital user
interface)
1. Make sure that there is tension in the recoil spring.
Replace the recoil spring if it is necessary.
2. Put the recoil spring in the power trigger.
3. Install the power trigger.
4. Make sure that the switch lever is above the switch
engage pin on the power trigger.
5. Make sure that the power trigger lockout has no
defects. Replace the power trigger lockout if it is
necessary.
6. Install the power trigger lockout.
1435 - 001 - 11.06.2020 Repair instructions - 17

7. Make sure that the edges of the power trigger and
the power trigger lockout are in the correct positions.
8. Assemble the crankcase. Refer to To disassemble
and assemble the crankcase on page 15 .
5.5.3 To disassemble the power trigger
(mechanical user interface)
1. Disassemble the crankcase. Refer to To
disassemble and assemble the crankcase on page
15 .
2. Make a note of how the inner parts of the power
trigger handle are installed.
3. Remove the power trigger lockout.
4. Make sure that the power trigger lockout has no
defects. Replace the power trigger lockout if it has
defects.
5. Remove the power trigger.
6. Pull out the recoil spring from the power trigger.
7. Make sure that there is tension in the recoil spring.
Replace the recoil spring if it is necessary.
8. Remove the main switch piston (A).
B
A
9. Pull out the main switch (B) and disconnect it.
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5.5.4 To assemble the power trigger (mechanical
user interface)
1. Connect and Install the main switch (A).
B
A
2. Make sure that there is tension in the recoil spring.
Replace the recoil spring if it is necessary.
3. Install the recoil spring in the power trigger.
4. Install the power trigger.
5. Make sure that the recoil spring is below the plastic
molding boss before you install the throttle trigger
lockout.
6. Make sure that the power trigger lockout has no
defects. Replace the power trigger lockout if it is
necessary.
7. Install the power trigger lockout.
8. Make sure that the edges (A) of the power trigger
and the power trigger lockout are in the correct
positions.
A
9. Assemble the crankcase. Refer to To disassemble
and assemble the crankcase on page 15 .
1435 - 001 - 11.06.2020 Repair instructions - 19

5.6 Front handguard
5.6.1 To remove and install the front handguard
1. Disassemble the crankcase. Refer to To
disassemble and assemble the crankcase on page
15 .
2. Remove the screw.
3. Carefully turn the front handguard to remove it from
the crankcase half.
4. Install in the opposite sequence.
5.7 Motor and control unit
5.7.1 To remove the motor, control unit and battery
connector
CAUTION: Do not pull the cables.
1. Remove the drive sprocket cover. Refer to Drive
sprocket and guide bar on page 11 .
2. Remove the drive sprocket. Refer to To remove and
install the drive sprocket on page 11 .
3. Remove the brake drum. Refer to To remove and
install the brake drum on page 12 .
4. Remove the worm gear. Refer to
To remove and
install the worm gear on page 12 .
5. Disassemble the crankcase. Refer to To
disassemble and assemble the crankcase on page
15 .
6. Disassemble the power trigger. Refer to Power
trigger on page 16 .
7. Remove the user interface. Refer to User interface
on page 23 .
8. Make a note of how the cables and parts are
installed.
9. Remove the 2 screws on the battery connector.
10. Remove the 3 screws and the motor unit.
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