NZQA Expiring unit standard
15404 version 4
Page 1 of 5
Title
Demonstrate knowledge of diesel engine air intake and exhaust
systems, and inspect and test them
Level
3
Credits
6
Purpose
This unit standard is for people in the automotive repair
industry. People credited with this unit standard are able to:
demonstrate knowledge of an induction system on a diesel
engine; demonstrate knowledge of an exhaust system on a
diesel engine; demonstrate knowledge of the operating
conditions for a vehicle and/or machine equipped with a
turbocharged engine; inspect and test the induction system on
a diesel engine for faults; and inspect and test the exhaust
system on a diesel engine for faults.
Classification
Motor Industry > Automotive Fuel Systems and Exhaust
Available grade
Achieved
Explanatory notes
1
The following legislation and amendments are required to be consulted and followed
where applicable:
Health and Safety in Employment Act, 1992.
2
Reference to suitable tools and test equipment means industry approved tools and
equipment that are recognised within the industry as being the most suited to
complete the task to a professional and competent manner with due regard to safe
working practices.
3
Unit standard Range for this unit standard includes both two and four stroke diesel
engines.
4
Because of the particular nature of this unit standard, it is essential that the practical
assessment evidence is obtained from commercial jobs in the workplace under
normal workplace conditions.
NZ Motor Industry Training Organisation
(Incorporated)
SSB Code 101542
 New Zealand Qualifications Authority 2016
NZQA Expiring unit standard
15404 version 4
Page 2 of 5
Outcomes and evidence requirements
Outcome 1
Demonstrate knowledge of an induction system on a diesel engine.
Evidence requirements
1.1
Air volumes required of an engine are compared.
Range
1.2
Main components of a turbocharger system are identified according to
manufacturer’s workshop manual illustrations.
Range
1.3
air intake, compressor, turbine, exhaust manifold, wastegate, oil
supply, intercooler.
Principles of turbocharging are described according to engine manufacturer’s
specifications.
Range
1.4
naturally aspirated, with a turbocharger, with a blower.
turbocharger location, volumetric efficiency, engine performance,
boost pressure, exhaust gas circulation, lubrication and cooling,
pressure control including electronic.
Principles of a Rootes type blower are described according to engine
manufacturer’s specifications.
Range
blower location, volumetric efficiency, engine performance, forced
air pressure circulation, lubrication and cooling, pressure control.
Outcome 2
Demonstrate knowledge of an exhaust system on a diesel engine.
Evidence requirements
2.1
Exhaust size and air flow rates of an exhaust system are compared.
Range
2.2
naturally aspirated engine, turbocharged engine.
Requirements of an exhaust system to produce back pressure according to
manufacturer’s specifications are determined and calculated.
NZ Motor Industry Training Organisation
(Incorporated)
SSB Code 101542
 New Zealand Qualifications Authority 2016
NZQA Expiring unit standard
15404 version 4
Page 3 of 5
Outcome 3
Demonstrate knowledge of the operating conditions for a vehicle and/or machine equipped
with a turbocharged engine.
Evidence requirements
3.1
Driver operational requirements for a turbocharged engined vehicle and/or
machine are identified.
Range
3.2
Importance of specified clean oil delivery to the turbocharger is identified.
Range
3.3
start-up procedures, shut-down procedures, servicing
requirements.
vehicle or machine manufacturer’s engine oil specifications, oil
and filter change recommendations, turbocharger oil requirements.
Hazards of unfiltered air entering the turbocharger system are identified.
Range
damage to components, dusty operating conditions, air intake
condition.
Outcome 4
Inspect and test the induction system on a diesel engine for faults.
Evidence requirements
4.1
Safe working practices are observed throughout the task.
Range
personal safety; safety of others; equipment, vehicle, and machine
safety.
4.2
Test equipment is mounted on the engine to enable inlet system restrictions to
be identified.
4.3
Air pressure readings are measured according to manufacturer’s instructions,
and the results are recorded.
4.4
Induction system is inspected according to manufacturer’s workshop manual
instructions, and any faults found are reported to the supervisor.
Range
scoop, prefilters, filters, pipework, elements, hoses, clamps,
mounts.
NZ Motor Industry Training Organisation
(Incorporated)
SSB Code 101542
 New Zealand Qualifications Authority 2016
NZQA Expiring unit standard
15404 version 4
Page 4 of 5
Outcome 5
Inspect and test the exhaust system on a diesel engine for faults.
Evidence requirements
5.1
Safe working practices are observed throughout the task.
Range
personal safety; safety of others; equipment, vehicle, and machine
safety.
5.2
Suitable tools and test equipment are selected according to manufacturer’s
specifications, and used to enable the system to be inspected and tested.
5.3
Test equipment is mounted on the engine to enable exhaust system restrictions
to be identified.
5.4
Exhaust system is inspected according to manufacturer’s workshop manual
instructions, and any faults found are reported to the supervisor.
Range
flanges, pipework, mufflers, spark arrestors, mountings.
5.5
Exhaust system faults and their causes identified by the test gauge readings are
noted.
5.6
Fuel lift tube, screens, and primary and secondary filters are inspected and
cleaned and/or replaced according to manufacturer’s recommendations.
5.7
Fuel hoses and connections are inspected and those found faulty are repaired
and/or replaced according to manufacturer’s specifications.
5.8
Fuel system is bled of air as prescribed by the engine manufacturer.
Replacement information
This unit standard and unit standard 930 have been
replaced by unit standard 24178, unit standard 24179,
and unit standard 24180.
This unit standard and unit standard 15403 replaced unit
standard 903.
This unit standard is expiring. Assessment against the standard must take place by
the last date for assessment set out below.
NZ Motor Industry Training Organisation
(Incorporated)
SSB Code 101542
 New Zealand Qualifications Authority 2016
NZQA Expiring unit standard
15404 version 4
Page 5 of 5
Status information and last date for assessment for superseded versions
Process
Version Date
Last Date for Assessment
Registration
1
26 February 1999
31 December 2016
Review
2
25 January 2008
31 December 2020
Rollover
3
19 November 2010
31 December 2020
Rollover
4
22 August 2014
31 December 2020
Consent and Moderation Requirements (CMR) reference
0014
This CMR can be accessed at http://www.nzqa.govt.nz/framework/search/index.do.
Please note
Providers must be granted consent to assess against standards (accredited) by NZQA,
before they can report credits from assessment against unit standards or deliver courses
of study leading to that assessment.
Industry Training Organisations must be granted consent to assess against standards by
NZQA before they can register credits from assessment against unit standards.
Providers and Industry Training Organisations, which have been granted consent and
which are assessing against unit standards must engage with the moderation system that
applies to those standards.
Requirements for consent to assess and an outline of the moderation system that applies
to this standard are outlined in the Consent and Moderation Requirements (CMR). The
CMR 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.
NZ Motor Industry Training Organisation
(Incorporated)
SSB Code 101542
 New Zealand Qualifications Authority 2016