Gunson COLORTUNE G4074 User manual

FAULTCODE READER OBD11
COLORTUNE
GASTESTER
EEZIBLEED
PROFESSIONAL
PART NO G4074 / G4170 / G4171 / G4172
HANDBOOK

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COLORTUNE
INDEX
Page
1.Application Details 4
2. Colortune Contents 5
3. General Precautions 6
4. How Colortune works 7
a. Combustion flame appearance
b.The Science
c.The practical details
5. Fitting Colortune to the engine 9
6. Simple engine tests with Colortune 10
7. Fuel system types 12
8. Engine fault finding with Colortune 16
9.Warranty 19

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1.Applications
Car and light commercial vehicles (Part No G4074)
Athread size of 14 mm has been used for nearly all cars and light vans produced in the last
50 years. One exception is the Ford SOHC Pinto engine (1970's) which was 18mm size
(adaptor available) and recently some vehicles have been introduced with smaller sizes due to
space restrictions on smaller 16 valve engines. Note:The hexagon size on 14mm plugs does vary
from 1980 onwards. A taper seat plug was introduced with a 16mm (5/8") hexagon (previously
13/16" or 20.6mm) and the 16mm hexagon size has also been used on flat seat varieties with a
revised body shape.
Motorcycles - 4 stroke (Part No G4170 / G4171 / G4172)
Athread sizeof 14 mm, 12mm or occasionally10mm, is used. The spark plug manufacturer’s
reference code helps with identification.These products has a smaller internal volume which
maintains the normal compression ratio and a higher heat range, more suited to high perform-
ance engines.
Motorcycles - 2 stroke
Athread size of 14 mm is almost universally used as there are no space restrictions caused by
valves.
Garden machinery and power plant engines
Athread size of 14 mm is generally used.

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2.Contents
The Colortune G4074
1. COLORTUNE plug-14mm size short reach with 16mm (5/8”) hexagonal body size.A hexagon
adaptor is provided to adapt to a 13/16” (20.6mm) plug spanner -also suitable for long reach
applications.
2. Solid cross section gas seal washer.
3. Extension H.T. lead incorporating an end suitable to connect either Champion or Continental
Bosch type suppressor caps (clip or thread)
4. Cleaning Brush
5.Viewerscope (two parts)
6. Instructions
The Motorcycle Colortune
G4170 - 14mm
G4171 - 12mm
G4172 - 10mm
1. COLORTUNE plug-Individually boxed with 10/12 or 14mm plug size, with reach with 16mm
(5/8”) hexagonal body size. A hexagon adaptor is provided to adapt to a 13/16” (20.6mm) plug
spanner -also suitable for long reach applications.
2. Solid cross section gas seal washer.
3. Extension H.T. lead incorporating an end suitable to connect either Champion or Continental
Bosch type suppressor caps (clip or thread).
4. Cleaning Brush
5.Viewerscope (two parts)
6. Instructions
Adaptors available for Colortune
10mm Part No 4055A
12mm Part No 4055B
14mm Part No 4055C
14mm Long Reach PartNo 4055D
18mm Part No 4055E
Colortune is available only in a short reach thread length but it may also be used in long reach
applications without any problem. It will still ignite the mixture and because it is only fitted for a
brief period therewill be no combustion carbon deposited on the exposed threads in the cylin-
der head.

3. General Precautions.
•Testing of vehicles is potentially hazardous.Take every precaution to avoid injury and ensure
that you have sufficient understanding of the task being undertaken. Seek advice or follow the
guidance of a comprehensive vehicle manual.
•Using this product involves working on a car while the engine is running. This is a potential
hazardand the user should take every precaution to avoid any possibility of damage or injury.
Never wear loose clothing that can catch in moving engine parts and always tie-up or cover
long hair. Do as much of the work as possible with the engine idle.
•Do not inhale exhaust gases - they are very poisonous. Always operate the vehicle in a well ven
tilated area.
•Always make sure the vehicle is in park (Automatic transmission) or neutral (manual
transmission) and that the parking brake is firmly set. Block the wheels as additional safeguard
if the vehicle is on sloping ground.
• Never lay metal tools on a vehicle battery. Always keep yourself and test equipment away
from moving or hot engine parts, remember that thermostatically controlled fans may
suddenly start with no warning. Treat high tension ignition components with respect, remem
bering that electrical shocks can cause involuntary movement which may result in secondary
injury.
• Never smokeor haveopen flames near the vehicle. Vapours from petrol or a charging battery
arehighlyflammable / explosive. Keep a suitable fire extinguisher handy. Use approved safety
equipment and eye protection where appropriate.
•Always turn ignition key OFF when connecting or disconnecting electrical components, unless
otherwise instructed. Never leave vehicle unattended while running tests.
• Keep children and pets awayfrom the vehicle while work is being carried out.
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