15380 version 3

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Demonstrate knowledge of carburettors used on outdoor powered equipment

Level / 3
Credits / 4

PurposeThis theory-based unit standard is for people in the outdoor power equipment repair industry. People credited with this unit standard are able to demonstrate knowledge of: carburettor operation used on outdoor powered equipment; basic carburettor service checks; and carburettor fault diagnosis and repair procedures.

Subfield / Motor Industry
Domain / Automotive Fuel Systems and Exhaust
Status / Registered
Status date / 25 January 2008
Date version published / 25 January 2008
Planned review date / 31 December 2012
Entry information / Open.
Accreditation / Evaluation of documentation and visit by NZQA and industry.
Standard setting body (SSB) / NZ Motor Industry Training Organisation (Incorporated)
Accreditation and Moderation Action Plan (AMAP) reference / 0014

This AMAP can be accessed at

Special notes

1Legislation relevant to this unit standard includes but is not limited to – Health and Safety in Employment Act 1992.

2Definition

Service information may include but is not limited to – technical information of a vehicle, machine, or product detailing operation; installation and servicing procedures; manufacturer instructions and specifications; technical terms and descriptions; and detailed illustrations. This can be accessed in hard copy or electronic format and is normally sourced from the manufacturer.

Elements and performance criteria

Element 1

Demonstrate knowledge of carburettor operation used on outdoor powered equipment.

Performance criteria

1.1The functions of float type carburettor components are described in accordance with service information.

Rangeventuri, main nozzle, choke valve, main air bleed, idle air bleed, float, inlet needle and seat, throttle valve, main jet, power jet, bowl vent.

1.2The functions of diaphragm (pressure differential) carburettor components are described in accordance with service information.

Rangediaphragm, throttle valve, inlet needle and seat assembly, main nozzle and ball check valve, choke valve, throttle valve, atmospheric vent, idle and main mixture adjustments, fixed jets.

1.3The operation of a float type carburettor and a diaphragm type carburettor are described in accordance with service information.

Rangechoke or start position, idle, intermediate, high speed.

1.4The operation of a fuel primer is described in accordance with service information.

Rangeremote primer, integral part of the carburettor.

1.5The operation of impulse fuel pumps are described in accordance with service information.

Rangeactuation of the diaphragm and flap valves.

Element 2

Demonstrate knowledge of basic carburettor service checks.

Performance criteria

2.1Carburettor pre-set adjustment procedures are described in accordance with service information.

Rangeidentifying carburettor model and manufacturer, governor adjustments, speed controls and linkage, normal maintenance procedures (oil changed, fresh fuel, air filter cleaned, air filter replaced, mixture screw pre-sets).

2.2Final adjustment procedures are described in accordance with service information.

Rangenormal operating temperature, adjusting main mixture setting, setting idle, setting slow position.

2.3Procedures to check lines, hose condition and connections are described in accordance with service information.

Rangehose perished, hose deteriorated, fuel tap blocked, fuel leaks, component damage, component security.

2.4Procedure to check fuel supply is described in accordance with service information.

Rangefuel pump, float level, fuel tank, filters, fuel line, primer.

2.5Procedure to check air supply is described in accordance with service information.

Rangeair filter, gaskets, component security.

Element 3

Demonstrate knowledge of carburettor fault diagnosis and repair procedures.

Performance criteria

3.1Safe working practices when diagnosing and repairing carburettor faults are described in accordance with service information, legislative requirements and relevant material safety data sheets (MSDS).

Rangeeffects of petrol on the skin, dealing with petrol spills, fire risk, effects of petrol on components, danger of moving parts on a running engine, danger of petrol fumes, danger of exhaust fumes, using compressed air.

3.2Carburettor faults and their causes are described in accordance with service information.

Rangeflat spot and hesitation, poor idle, flooding, fuel leaks, poor high speed operation, engine hard to start.

3.3Procedures for dismantling, cleaning, inspecting, repairing and replacing components, and reassembling a carburettor are described in accordance with service information.

Rangefloat type, diaphragm type.

Please note

Providers must be accredited by NZQA, or an inter-institutional body with delegated authority for quality assurance, before they can report credits from assessment against unit standards or deliver courses of study leading to that assessment.

Industry Training Organisations must be accredited by NZQA before they can register credits from assessment against unit standards.

Accredited providers and Industry Training Organisations assessing against unit standards must engage with the moderation system that applies to those standards.

Accreditation requirements and an outline of the moderation system that applies to this standard are outlined in the Accreditation and Moderation Action Plan (AMAP). The AMAP also includes useful information about special requirements for organisations wishing to develop education and training programmes, such as minimum qualifications for tutors and assessors, and special resource requirements.

Comments on this unit standard

Please contact the NZ Motor Industry Training Organisation (Incorporated) if you wish to suggest changes to the content of this unit standard.

 New Zealand Qualifications Authority 2018