Husqvarna K970 III Ring Instruction manual

Workshop manual
K970 III
English
1444 - 001 - 02.04.2020

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
3 Servicing data
3.1 Symbols in the diagrams........................................5
3.2 Tightening torques ................................................ 6
4 Servicing tools
4.1 Servicing tools overview.......................................10
4.2 Servicing tools overview.......................................11
4.3 Servicing tools overview.......................................12
5 Product overview for repair and servicing
5.1 Product overview .................................................13
5.2 Basic modules of the product...............................14
6 Repair and servicing
6.1 Starter.................................................................. 22
6.2 Ignition system..................................................... 26
6.3 Flywheel............................................................... 30
6.4 Air filter................................................................. 32
6.5 Fuel system..........................................................33
6.6 Carburetor............................................................ 37
6.7 Decompression valve...........................................42
6.8 Cylinder and piston.............................................. 43
6.9 Piston wear.......................................................... 46
6.10 To assemble the piston...................................... 47
6.11 To assemble the cylinder................................... 48
6.12 Crankcase.......................................................... 49
6.13 Clutch................................................................. 55
6.14 Cutting head.......................................................58
6.15 Wet system........................................................ 63
6.16 Throttle trigger and throttle trigger lockout......... 64
7 Troubleshooting
7.1 Engine does not start........................................... 67
7.2 Engine stops during operation - no sparks...........68
7.3 Engine stops during operation............................. 68
7.4 Weak output or change of speed......................... 69
7.5 Other engine problems.........................................69
21444 - 001 - 02.04.2020

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.
1444 - 001 - 02.04.2020 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
• Do not repair the product unless you have read and
understood this workshop manual.
• The service center where the product is repaired
must have safety equipment approved by local
bylaws.
• The product is examined and approved only with the
equipment given or recommended by the
manufacturer.
• Prevent health and safety risks. All personnel must
obey laws and requirements when they do the
procedures given in this manual.
• Obey the local waste regulations.
• Always make sure that all nuts and bolts are
correctly tightened.
• Use protective gloves and eye protection. Goggles
must obey the ANSI Z87.1 for US or EN166 for EU
countries.
• When using compressed air, do not point it to your
body. Air can go into the bloodstream.
• Use hearing protection when the engine is started.
• The product can make sparks and cause ignition of
flammable materials.
• Replace all damaged or missing warning symbol
decals.
• Gasoline and its fumes are poisonous.
• Gasoline can cause damage to the eyes and the
skin.
• Gasoline can cause breathing problems.
• Gasoline is flammable.
2.3 Symbols on the product
WARNING: Careless or incorrect use can
result in injury or death to the operator or
others.
Read the manual carefully and make sure
you understand the instructions before
using the product.
Always put on personal protective
equipment:
• Hearing protection
• Protective goggles or a visor
• Breathing mask.
This product in compliance with applicable
EC directives.
WARNING! Dust from cutting can cause
breathing problems. Use breathing
protection. Do not breathe exhaust fumes.
Always make sure there is good airflow.
WARNING! Sparks from the cutting blade
can cause a fire in materials such as,
gasoline, wood, fabric and dry grass.
WARNING! Kickbacks can be sudden,
fast and can cause injuries. Read and
understand the instructions in the manual
before using the product.
Make sure the cutting disc is not
damaged.
WARNING! Do not use circular saw
blades.
Note: Other symbols/decals on the product refer to
special certification requirements for some markets.
4 - Safety 1444 - 001 - 02.04.2020

3 Servicing data
3.1 Symbols in the diagrams
Tightening torque, Nm
1444 - 001 - 02.04.2020 Servicing data - 5

3.2 Tightening torques
9,0-11,0
9,0 -11,0
9,0-11,0
10,0-12,0
9,0-11,0
3,0-5,0
7,0-9,0
3,0-4,0 3,0-4,0
2,0-3,0
17,0-23,0
6 - Servicing data 1444 - 001 - 02.04.2020

14,0-16,0
5,0-7,0
11,0-13,0
16,0-18,0
10,0-18,0
5,0-7,0
5,0-7,0
1444 - 001 - 02.04.2020 Servicing data - 7

4,0-10,0
8,0-10,0
5,0-7,0
25,0-30,0
4,0-5,0
38,0-42,0
8 - Servicing data 1444 - 001 - 02.04.2020

6,0-8,0
12,0-14,0
35,0-40,0
20,0-25,0
25,0-30,0
7,0-10,0
7,0-10,0
14,0
2,0-3,0
7,0-9,0
3,0-4,0
17,0
2,0-3,0
2,0-3,0
14,0
1444 - 001 - 02.04.2020 Servicing data - 9

4 Servicing tools
4.1 Servicing tools overview
4 5 6
7 8
1 2 3
9
Po-
si-
tion
Designation Used for Order No./Source
1 Sealing plug To examine the crankcase for leaks. 503 55 22-01
2 Bearing press To assemble the primary bearing. 506 37 61-02
3 Press tool To disassemble and assemble the blade shaft bearings and axle. 575 96 20-01
4 Puller To disassemble the sealing rings of the crankcase in the crank-
case.
504 91 40-01
5 Assembly punch To assemble the sealing rings of the crankshaft in the crankcase. 502 50 82-01
6 Bearing press To disassemble and assemble the clutch drum ball bearing and
blade shaft bearing.
504 56 79-01
7 Universal puller To disassemble the support washer of the clutch on the crank-
shaft. To divide the crankcase.
504 90 90-02
8 Fuel filter hook To catch the fuel filter in the tank. 502 50 83-01
9 Special screwdriver To adjust the idle speed. 501 60 02-03
10 - Servicing tools 1444 - 001 - 02.04.2020