RedMax GZ5000 Instruction manual

Workshop Manual
English
GZ5000

English - 1
Workshop Manual
GZ5000
Contents
Index ................................................................................................ 4
Introduction and safety instructions .................................... 6
Technical data..............................................................................10
Service tools ................................................................................12
Service data..................................................................................14
Safety equipment ......................................................................18
Repair instructions.....................................................................29
Carburettor ..................................................................................38
Troubleshooting .........................................................................66
Contents
Husqvarna AB has a policy of continuous product development and therefore reserves the right to modify
the design and appearance of products without prior notice.

2- English
Index
Index
B
Bar bolt 65
Replacing the bar bolt 65
C
Carburettor 38
Assembly 42
Cleaning and inspection 42
Design 38
Dismantling 40
Function 39
Pressure testing the carburettor 44
Centrifugal clutch 34
Assembly of centrifugal clutch 35
Cleaning and inspection 34
Dismantling the centrifugal clutch 34
Chain brake 19
Assembling the chain brake 20
Cleaning and inspection 19
Dismantling the chain brake 19
Chain catcher 24
Replacing the chain catcher 24
Crankshaft and crankcase 59
Assembling a complete crankshaft 61
Dismantling the crankcase and crankshaft 59
F
Fuel system 48
Replacing the fuel lter 48
Replacing the fuel hose 48
I
Ignition module and ywheel 32
Assembling the ignition module and ywheel 33
Cleaning and inspection 32
Dismantling the ignition module and ywheel 32
Intake system 36
Assembling the intake system 37
Cleaning and inspection 37
Dismantling the intake system 36
Introduction and safety instructions 7
General 7
General Instructions 8
Modications 7
Numbering 7
Safety 7
Special Instructions 8
Structure 7
Target group 7
Tools 7
M
Muer 23
Assembling the muer 23
Dismantling the muer 23
O
Oil pump and screen 35
Assembling the oil pump and screen 36
Cleaning and inspection 35
Dismantling the oil pump and screen 35
P
Piston and cylinder 55
Assembling the piston and cylinder 57
Dismantling the piston and cylinder 55
Faults and causes 57
Pressure testing the cylinder 57
S
Service data 14
Service tools 12
Starter 29
Cleaning and inspection 29
Dismantling the starter 29
Replacing a broken or worn starter cord 30
Tensioning the return spring 30
Replacing a broken return spring 31
Starter assembly 31
Stop control 24
Dismantling the stop control 24
Stop function 25
Resistance test - stop function 25
Symbols
Symbols in the Workshop Manual 9
Symbols on the chain saw 9
T
Tank unit 46
Assembly 47
Dismantling 46
Tank valve 46
Technical Data 10
Threads 64
Repairing damaged threads 64
Throttle control lock, throttle lock and spring 26
Assembling the throttle lockout, throttle control
and spring 27
Cleaning and inspection 26
Dismantling the throttle control lock, throttle
control and spring 26
Troubleshooting 66
Troubleshooting methods 67
V
Vibration damping system 47

English - 3
Index
Assembly 47
Cleaning and inspection 47
Dismantling 47

4- English
Introduction and safety instructions
2 Introduction and safety regulations
Contents
2.1 General ..........................................................................................................................................................................7
2.2 Safety .............................................................................................................................................................................7
2.3 Target group ................................................................................................................................................................7
2.4 Modications...............................................................................................................................................................7
2.5 Tools ...............................................................................................................................................................................7
2.6 Structure .......................................................................................................................................................................7
2.7 Numbering ..................................................................................................................................................................7
2.8 General instructions .................................................................................................................................................8
2.9 Special instructions ..................................................................................................................................................8
2.10 Symbols on the saw .................................................................................................................................................9
2.11 Symbols in the Workshop Manual ......................................................................................................................9

English - 5
2 Introduction and safety instructions
Introduction and safety instructions
2.1 General
This Workshop Manual describes in detail how
to be troubleshoot, repair and test the chain saw.
Adescription of dierent safety steps that must be
taken during repair work is also given.
2.2 Safety
Note: The section dealing with safety must be
read and understood by all those carrying out
repair work or service on the chain saw.
Warning symbols can be found in this Workshop
Manual and on the chain saw. See “Symbols on
the saw” and“Symbols in the Workshop Manual”.
A new warning symbol decal must be applied as
soon as possible if a warning symbol on the chain
saw has been damaged or is missing so that the
greatest level of safety can be maintained when
using the chain saw.
2.3 Target group
This Workshop Manual is written for personnel who
are assumed to have general knowledge of repair-
ing and servicing chain saws.
The Workshop Manual must be read and under-
stood by personnel who will carry out repair work
and service on the chain saw. The Manual is also
suitable for use when training new employees.
2.4 Modications
Any modications to the chain saw will be gradually
introduced into ongoing production. As these modi-
cations aect service and/or spare parts, specic
service information will be sent out on each occa-
sion. This means that in time this Workshop Manu-
al will become out of date. In order to prevent this,
the Manual should be read together with all service
information concerning the chain saw in question.
2.5 Tools
Special tools are required for some stages. All
service tools are listed in the Workshop Manual.
Usage is made apparent in each section.
Always use Husqvarna’s original:
• Spare parts
• Service tools
• Accessories
2.6 Structure
This Workshop Manual can be used in two dierent
ways:
• Repair of a specic system on the chain saw.
• Dismantling and assembly of the entire chain saw.
Repair of a specic system
When a particular system on the chain saw is to be
repaired, proceed as follows:
1. Look up the page for the system in question.
2. Carry out the following steps:
Dismantling
Cleaning and inspection
Assembly
Dismantling and assembling the chain saw.
Proceed as follows when the chain saw is to be
dismantled and assembled:
1. Open the “Repair instructions” chapter which
deals with the Starter and carry out the in-
structions outlined under the Dismantling
heading.
2. Work forward in the Manual and carry out Dis-
mantling in the order set out in the sections.
3. Go back to the Starter and carry out the in-
structions under Cleaning and Inspection.
4. Work forward in the Manual and carry out
Cleaning and Inspection in the order set out
in the sections.
5. Order or collect all requisite spare parts from
the stores.
6. Look up the“Repair instructions”chapter which
deals with the Crankcase and carry out the
instructions outlined in Assembling.
7. Work back in the Manual and carry out Assem-
bling in the order set out in the sections.
Some sections include an introductory Descrip-
tion of the actual unit in order to increase the basic
understanding.
2.7 Numbering
Position references to components inside the g-
ures are designated A, B, etc.
The gures are numbered 1, 2 etc.
The position references and gure numbers restart
in each new section.

6- English
2.8 General Instructions
The workshop where the chain saw is to be re-
paired must be equipped with safety equipment in
accordance with local regulations.
No one may repair the chain saw unless they have
read and understood the content of this Workshop
Manual.
This workshop manual contains the following warn-
ing boxes in relevant places.
2.9 Special Instructions
The fuel used in the chain saw has the following
hazardous properties:
• The uid and its vapour are poisonous.
• Can cause eye and skin irritation.
• Can cause breathing problems.
• Is highly inammable.
When using compressed air, do not direct the jet
towards your body. Air can penetrate into the blood
stream, which can endanger life.
Wear protective earplugs or earmus when test
running.
After test running, do not touch the muer until
it has cooled down. Risk of burns. Use protective
gloves when working with the muer.
Do not start the chain saw unless the bar, chain
and clutch cover (chain brake) are tted, otherwise
the clutch may loosen and cause personal injury.
Insucient chain lubrication can result in chain
breakage, which can cause serious or even life-
threatening injury.
Exercise care to ensure the starter spring does not
y out and cause personal injury. Wear protective
glasses. If the spring tension is activated on the
starter pulley when it is to be taken up, the spring
can y out and cause personal injury.
Check that the brake is applied when removing the
pressure spring on the chain brake. Otherwise the
pressure spring can y out and cause personal
injury.
After repairing, check the chain brake, see “Assem-
bling chain brake \ Function check”.
Keep in mind the re risk. The chain saw may emit
sparks, which cause ignition.
Check the chain catcher and replace it if it is dam-
aged.
WARNING!
The warning box warns of the risk
of personal injury if the instruc-
tions are not followed.
NOTE!
This box warns of material damage if the
instructions are not followed.
Introduction and safety instructions

English - 7
Introduction and safety instructions
2.10 Symbols on the saw
The symbols below are embedded on the chain
saw.
Choke Lever
Refuelling
Stop button
Chain oil ll.
Chain brake
Decompression valve
Fuel pump
Adjusting the oil pump
Heated handles
2.11 Symbols in the Workshop Manual
This symbol warns of personal injury
when the instructions are not followed.
Use protective gloves.
Use protective goggles.

8- English
Displacement Cylinder diameter Stroke length Max. output/speed
cm3/cubic inch Ø mm/Ø inch mm/inch kW/hp/ rpm
GZ5000 50,1 / 3.06 43 / 1.69 34,5 / 1.36 2.8 / 3,8 / 9 600
Electrode gap Ignition system Air gap
mm/inch mm/inch
GZ5000 0,5 / 0,02 SEM-DM61 0,3 / 0,012
Usable cutting length Chain speed att 133% of Chain pitch Drive link
cm/inchmaximum engine power speed mm/inch mm/inch
ft/s / m/s
GZ5000 31-49 / 12-19 85.6 / 26,1 8,25 / 0.325 1,3 / 0.050 - 1,5 / 0.058
3 Technical data
Technical data

English - 9
Engage speed Spark plug Type of oil pump
rpm
GZ5000 4 200 NGK CMR6H Adjustable
Volume fuel tank Capacity oil pump at Volume oil tank
Litre/US. pint 9,000 rpm, Litre/US. pint
ml/min
GZ5000 0,52 / 0.94 5-12 0,27 / 0.57
OIL
Technical data
Weight without bar and chain Heated handles Electrical carburettor
kg / lbs kg / lbs heating
GZ5000 4,9 / 10.8 - -

10 - English
6
10 11
4 Service tools
Service tools
35
8
1 2
79
4 mm
5 mm
4
4 mm
12a
12b

English - 11
Pos Description Used for Order No.
1 Piston stop Locking the crankshaft 575 29 36-01
2 Hook for fuel lter Suspending the fuel lter 502 50 83-01
3 Allen key, 4 mm For M5 bolts 502 50 87-01
4 Allen key, 4 mm For M5 bolts 502 50 18-01
4 Allen key, 5 mm For M6 bolts 502 50 64-01
5 Air gap tool Setting, ignition module 502 51 34-02
6 Clutch tool Centrifugal clutch 502 54 16-02
7 Assembly xture Securing the chain saw 502 51 02-01
8 Pressure gauge Pressure testing 531 03 06-23
9 Test spark plug Checking the ignition module 501 97 64-01
10 Assembly pliers Fitting the spark plug guard 502 50 06-01
11 Dismantling device Dismantling the crankcase 575 28 69-01
12a Assembly tool Assembling the sealring 575 34 70-01
12b Guide sleeve Assembling the sealring 575 34 69-01
13a Cover plate, inlet Closure of inlet 574 71 14-01
13b Cover plate, outlet Closure of outlet 578 04 18-01
13c Cover plug, inlet Closure of inlet 578 02 13-01
13d Pressure tester Pressure testing the cylinder 503 84 40-03
14 Mandrel Dismantling the ywheel 502 51 94-01
15 Assembly tool Assembling the crankshaft 502 50 30-23
16 Puller Dismantling the crankshaft 531 00 48-67
17 Engine Diagnostic Tool Diagnosis and troubleshooting 576 69 23-01
18 Silicone tube Assembling piston and cylinder 503 26 72-01
19 T-handle Torx T10 For torx screws 588 52 41-01
19 T-handle Torx T20 For torx screws 588 59 85-01
19 T-handle Torx T27 For torx screws 502 71 27-03
Service tools
14
13c
13b 16
17
13a13d
15 18 19

12 - English
5 Service data - Allen
Service data - Allen screws
8-10Nm 4mm
18-20Nm 16mm
12-14Nm 13mm
1,5-2Nm 4mm
5-6Nm 4mm
4-5Nm 4mm
25Nm
15Nm 13mm
1-2Nm
16-20Nm 5mm
14-16Nm 5mm
1-2Nm
s = Lubricate using two-stroke oil.
n = Lubricate using chain oil.
l = Lubricate using grease.
The numbers by the components to be
assembled with screws state the tightening
torque in Nm.
Key

English - 13
Service data - Allen screws
9-11Nm 4mm
1-2Nm
7-9Nm 4mm
22-25Nm 13mm
6-8Nm 4mm
9-11Nm 4mm
6-8Nm 4mm
4-5Nm 4mm
3,5-4,5Nm 4mm 3,5-4,5Nm 4mm
3,5-4,5Nm 4mm
3-4Nm 4mm
7-9Nm 4mm
3-4Nm 4mm
3-4Nm 4mm

14 - English
5 Service data - Torx
Service data - Torx screws
8-10Nm
18-20Nm 16mm 1,5-2Nm
5-6Nm
4-5Nm
25Nm
15Nm 13mm
1-2Nm
16-20Nm
14-16Nm
1-2Nm
1- Nm
12-14Nm 13mm
s = Lubricate using two-stroke oil.
n = Lubricate using chain oil.
l = Lubricate using grease.
The numbers by the components to be
assembled with screws state the tightening
torque in Nm.
Key

English - 15
Service data - Torx screws
- Nm
1-2Nm
7-9Nm
22-25Nm 13mm
7-9Nm
- Nm
- Nm
- Nm
- Nm
- Nm
- Nm
- Nm
- Nm
- Nm
- Nm
- Nm
- Nm Nm
Nm
- Nm
Nm

16 - English
6 Safety equipment
Safety equipment
Contents
6.1 Dismantling the chain brake .................................................................................................................................19
6.2 Assembling the chain brake ..................................................................................................................................20
6.3 Dismantling the right-hand brake trigger .......................................................................................................21
6.4 Assembling the right-hand brake trigger ........................................................................................................23
6.5 Dismantling the muer ..........................................................................................................................................23
6.6 Assembling the muer ..........................................................................................................................................23
6.7 Replacing the chain catcher ..................................................................................................................................24
6.8 Dismantling the start/stop control .....................................................................................................................24
6.9 Assembling the start/stop control ......................................................................................................................25
6.10 Resistance test - stop function .............................................................................................................................25
6.11 Dismantling the throttle control lock, throttle control and spring .........................................................26
6.12 Assembling the throttle control lock, throttle control and spring ..........................................................27

English - 17
3
Loosen the screws and insert a screwdriver to
maintain pressure on the spring, and then carefully
remove the cover over the brake spring, see g. 3.
WARNING!
Exercise care to ensure the spring
does not y out and cause personal
injury. Wear protective goggles.
6.1 Dismantling the chain brake
2
Unscrew the kickback guard and remove it.
NOTE! Make sure that the spring and rocker do not
y out.
Carefully tighten the clutch housing in a vice. Re-
lease the brake by using the saw’s hand guard as
a tool. Mesh with the brake and tighten anti-clock-
wise until the brake is activated, see g. 2.
Cleaning and inspection
• Clean and check carefully all components. Parts
must be replaced if cracked or show signs of
other defects. Always use original spare parts.
• Measure the thickness of the chain brake band.
It must not be less than 0.6 mm in any place.
See gure 5.
• Lubricate the knee joint with grease.
4
Hold one hand on top of the brake spring and
press in a small screwdriver into the spring. Care-
fully bend upwards until the spring is released and
it slides onto the screwdriver, see g. 4.
Safety equipment
6 Safety equipment
1
Remove the cylinder cover.
Release the brake by moving the front hand guard
backward.
Loosen the bar nuts and remove the clutch cover,
bar and chain, see g. 1. Fig 1
Fig 2
Fig 3
Fig 4
Fig 5
Alt. 1
Alt. 2

18 - English
6.2 Assembling the chain brake
1
Screw the knee joint and the brake band together
(see gure 5) using a tightening torque of 1-1.5
Nm. Place the knee joint with the tted chain brake
band in the opening in the clutch cover. The space
for the spring in the cover must be lubricated with
grease. See gure 6.
2
Compress the spring with a wide screwdriver and
press it down with your thumb. See gure 7.
3
Fit the cover over the brake spring using 1-1.5 Nm
tightening torque. See gure 8.
WARNING!
Exercise care to ensure the spring
does not y out and cause personal
injury. Wear protective goggles.
4
Tighten the brake by using the saw’s hand guard
as a tool. Mesh with the brake and tighten clock-
wise until the brake is in the o position. See
gure9.
5
NOTE! Make sure the bushings in the kickback
guard’s attachments are kept in place from the
inside. See gure 9.
Screw the kickback guard in place and put the
rocket in position. Position the spring (B) in the
plastic housing (C) (see gure 10) and press the
spring against the rocker and then press the plastic
housing into its groove. Tighten the chain guide
plate in place.
Fit the:
• The bar
• The chain
• The clutch cover
• The cylinder cover
Safety equipment
Fig 6
Fig 7
Fig 8
Fig 9
A
B
C
Fig 10

English - 19
NOTE!
After repairing, the chain brake must be in-
spected in line with the instruction below.
Functional inspection:
Do not turn on the motor when carrying out this
inspection.
Bar length Height
38 cm/15” 50 cm/20"
• Hold the chain saw over a stable surface. The
distance between the bar and the surface is
shown in the table above.
• Let go of the front handle and let the chain saw
drop toward the surface underneath.
• When the bar hits the surface the chain brake
must trigger.
Safety equipment
Fig 11
6.3 Dismantling the right-hand brake
trigger
1
Release the brake by moving the front hand guard
towards the front handle. Loosen the bar nuts and
remove the clutch cover, bar and chain, see g. 1.
2
Loosen the screws D and remove the front handle,
see g. 2.
DD
D
D
D
Fig 1
Fig 2