AURT 3046666 A REPAIR AND AUTOMOTIVE MECHANICAL TECHNOLOGY

AURT 3046666 A REPAIR AND AUTOMOTIVE MECHANICAL TECHNOLOGY AUR 30405 CERTIFICATE III IN REPLACE EMISSION CONTROL SYSTEMS AURT 304666 A Repair and replace emission control systems © Commonwealth of Australia 2011 AURT 3046666 A Repair and replace emission control systems

AURT 3046666 A REPAIR AND REPLACE EMISSION CONTROL SYSTEMS 2 Personal safety • Use personal protective equipment (PPE). • Use wheel chocks & guard covers. • Keep clear of hot or moving components on engines. • Lift vehicles correctly and safely. • Plenty of ventilation when working on running engines. © Commonwealth of Australia 2011 AURT 3046666 A Repair and replace emission control systems

AURT 3046666 A REPAIR AND REPLACE EMISSION CONTROL SYSTEMS 3 Forms of pollution Pollution from evaporation © Commonwealth of Australia 2011 Pollution from combustion AURT 3046666 A Repair and replace emission control systems

AURT 3046666 A REPAIR AND REPLACE EMISSION CONTROL SYSTEMS 4 Producing exhaust gases Fuel is injected into the engine Air enters the engine Combustion Exhaust gas exits the engine Blow by © Commonwealth of Australia 2011 AURT 3046666 A Repair and replace emission control systems

AURT 3046666 A REPAIR AND REPLACE EMISSION CONTROL SYSTEMS 5 Sources of emissions Fuel tanks and carburettors 10% by evaporation Exhaust 60% from combustion Crankcase 30% from combustion and blow by © Commonwealth of Australia 2011 AURT 3046666 A Repair and replace emission control systems

AURT 3046666 A REPAIR AND REPLACE EMISSION CONTROL SYSTEMS 6 Emissions from petrol engines Hydrocarbons (HC) come from: • unburnt fuel • evaporating fuel • crankcase vapours or blow by gases © Commonwealth of Australia 2011 AURT 3046666 A Repair and replace emission control systems

AURT 3046666 A REPAIR AND REPLACE EMISSION CONTROL SYSTEMS 7 Emissions from petrol engines Carbon monoxide (CO) comes from: • incomplete combustion due to a lack of oxygen(air) during combustion • excessively rich fuel/air mixtures • very lean fuel/air mixtures © Commonwealth of Australia 2011 AURT 3046666 A Repair and replace emission control systems

AURT 3046666 A REPAIR AND REPLACE EMISSION CONTROL SYSTEMS 8 Emissions from petrol engines Oxides of nitrogen (NOx) come from: • overheating engine conditions • increased compression ratios • incorrect ignition timing • lean fuel mixtures. © Commonwealth of Australia 2011 AURT 3046666 A Repair and replace emission control systems

AURT 3046666 A REPAIR AND REPLACE EMISSION CONTROL SYSTEMS 9 Government legislation Guidelines for 6 tests: 1. Exhaust emissions after a cold start. 2. Carbon monoxide emission test at idling speed. 3. Emissions of crankcase gases. 4. Evaporative emissions from vehicles with positive-ignition engines. 5. Endurance test for durability of pollution control devices. 6. Average exhaust emissions of carbon monoxide and hydrocarbons after a cold start at low ambient temperature. © Commonwealth of Australia 2011 http: //www. comlaw. gov. au/ AURT 3046666 A Repair and replace emission control systems

AURT 3046666 A REPAIR AND REPLACE EMISSION CONTROL SYSTEMS 10 Emissions from diesel engines Particulates • carbon particles in the exhaust gas • formed due to: – incomplete combustion – slow and cold engine operation – high engine oil consumption. Oxides of nitrogen (NOX) • formed due to high combustion temperatures in diesel engines. © Commonwealth of Australia 2011 AURT 3046666 A Repair and replace emission control systems

AURT 3046666 A REPAIR AND REPLACE EMISSION CONTROL SYSTEMS 11 Government legislation National Environment Protection Measure (Diesel Vehicle Emissions) 2001, amended in 2009 www. nepc. gov. au © Commonwealth of Australia 2011 AURT 3046666 A Repair and replace emission control systems

AURT 3046666 A REPAIR AND REPLACE EMISSION CONTROL SYSTEMS 12 Types of emission control systems 1. Evaporative control Prevents fuel vapour escaping to the atmosphere 2. Crankcase ventilation Prevents crankcase emissions escaping to the atmosphere 3. Exhaust emission control Controls the products of combustion before they enter the atmosphere © Commonwealth of Australia 2011 AURT 3046666 A Repair and replace emission control systems

AURT 3046666 A REPAIR AND REPLACE EMISSION CONTROL SYSTEMS 13 Evaporative emission control system Charcoal canister Vapour line to canister Liquid/valve separator Fuel tank Carburettor Petrol cap relief valve Vapour vent Air vent solenoid valve © Commonwealth of Australia 2011 Purge line Fuel line AURT 3046666 A Repair and replace emission control systems

AURT 3046666 A REPAIR AND REPLACE EMISSION CONTROL SYSTEMS 14 Evaporative emission control system Stops fuel vapour escaping into the atmosphere: • Seals the fuel tank and carburettor. • Temporarily stores the fuel vapour. • Regularly flushes out the stored fuel vapour. © Commonwealth of Australia 2011 AURT 3046666 A Repair and replace emission control systems

AURT 3046666 A REPAIR AND REPLACE EMISSION CONTROL SYSTEMS 15 Charcoal Canister Fuel vapour line from carburettor Throttle ported vacuum Line to intake manifold Fuel vapour line from tank • Stores the evaporating fuel from the tank and carburettor (if fitted). Filter • When the engine starts the stored fuel vapour is sent to the engine. Charcoal Filter Air vent © Commonwealth of Australia 2011 AURT 3046666 A Repair and replace emission control systems

AURT 3046666 A REPAIR AND REPLACE EMISSION CONTROL SYSTEMS 16 Fuel tank and cap Stores the fuel. Fuel tank Prevents the fuel vapour from escaping to the atmosphere. Fuel filler cap Liquid vapour separator © Commonwealth of Australia 2011 AURT 3046666 A Repair and replace emission control systems

AURT 3046666 A REPAIR AND REPLACE EMISSION CONTROL SYSTEMS 17 Crankcase ventilation system PCV - Positive Crankcase Ventilation valve Valve spring Air filter • Prevents excessive pressure build up in the crankcase. • Prevents unburnt fuel vapour from escaping to the atmosphere. Shuttle valve Fresh air inlet Valve seat Intake manifold PVC valve Retaining spring Blowby gases Valve housing © Commonwealth of Australia 2011 Valve face Hose connection to inlet manifold Crankcase vapours & blowby gases AURT 3046666 A Repair and replace emission control systems

AURT 3046666 A REPAIR AND REPLACE EMISSION CONTROL SYSTEMS 18 Exhaust emission control systems Exhaust gases = more than 1/2 total emissions from vehicles. Three ways to reduce or control exhaust emissions: 1. Engine design 2. Exhaust Gas Recirculating system (EGR) 3. Catalytic converter. © Commonwealth of Australia 2011 AURT 3046666 A Repair and replace emission control systems

AURT 3046666 A REPAIR AND REPLACE EMISSION CONTROL SYSTEMS 19 Engine design Wedge shaped combustion chamber Hemispherical combustion chamber • large quench area • increased hydrocarbon emissions • minimal quench area • less hydrocarbon emissions © Commonwealth of Australia 2011 AURT 3046666 A Repair and replace emission control systems

AURT 3046666 A REPAIR AND REPLACE EMISSION CONTROL SYSTEMS 20 Exhaust Gas Recirculating system (EGR) • Returns some exhaust gas to intake manifold. • Lowers combustion temperature. • Reduces oxides of nitrogen (NOx) in exhaust gas. Vacuum port Exhaust gas port ERG valve Thermo valve Exhaust gas © Commonwealth of Australia 2011 AURT 3046666 A Repair and replace emission control systems

AURT 3046666 A REPAIR AND REPLACE EMISSION CONTROL SYSTEMS 21 Catalytic Converter Fitted to the vehicle exhaust system as close as possible to the engine. Tailpipe Engine pipe Muffler to tailpipe Muffler Pipe to muffler © Commonwealth of Australia 2011 Catalytic convertor AURT 3046666 A Repair and replace emission control systems

AURT 3046666 A REPAIR AND REPLACE EMISSION CONTROL SYSTEMS 22 Catalytic Converter Chemicals react with pollutants in exhaust gas To exhaust H 2 O - Water CO 2 - Carbon dioxide O 2 - Oxygen N - Nitrogen Pollutants from engine © Commonwealth of Australia 2011 HC - Hydrocarbons CO - Carbon monoxide NOx - Oxides of nitrogen AURT 3046666 A Repair and replace emission control systems

AURT 3046666 A REPAIR AND REPLACE EMISSION CONTROL SYSTEMS 23 Diesel particulate filter Clean exhaust out Exhaust in Soot and ash particles • Exhaust carrying particulate matter (PM) enters open channels. • Ends of channels are blocked forces exhaust through walls. • Pm is captured on the walls over time, pm burns away. © Commonwealth of Australia 2011 AURT 3046666 A Repair and replace emission control systems

AURT 3046666 A REPAIR AND REPLACE EMISSION CONTROL SYSTEMS 24 Emission Control Information label • 2005 ADR) 79/02 emission control regulations. • Must be in a visible position in the vehicle engine compartment. • Must state a range of engine specifications and adjustments. © Commonwealth of Australia 2011 AURT 3046666 A Repair and replace emission control systems

AURT 3046666 A REPAIR AND REPLACE EMISSION CONTROL SYSTEMS 25 Testing exhaust emissions Measure pollutants in exhaust gases with an exhaust gas analyser Good ventilation is critical when testing © Commonwealth of Australia 2011 AURT 3046666 A Repair and replace emission control systems

AURT 3046666 A REPAIR AND REPLACE EMISSION CONTROL SYSTEMS 26 © Commonwealth of Australia 2011 ISBN: 978 -1 -876838 -51 -5 This document is available under a “Free for Education” licence for educational purposes – see http: //www. aesharenet. com. au/Ff. E 2 for details. This work is copyright. You may download, display, print and reproduce this material in whole or in part or in modified form (retaining this notice) for your personal, non-commercial use or use within your organisation. If you use, display, or reproduce this material or a modified form of it in whole or in part within your organisation you must include the following words in a prominent location within the material in font not less than size 12: ‘The views expressed in this publication do not necessarily represent the view of the Minister for Education or the Australian Government. The Australian Government does not give any warranty nor accept any liability in relation to the contents of this work’. Apart from any use as permitted under the Copyright Act 1968, all other rights are reserved. Requests and inquiries concerning reproduction and rights should be addressed to the Commonwealth Copyright Administration, Attorney General’s Department, Robert Garran Offices, National Circuit, Barton ACT 2600 or posted at http: //www. ag. gov. au/cca. Funded under the Workplace English Language and Literacy (WELL) Program by the Australian Government Department of Education, Employment and Workplace Relations. The views expressed in this publication do not necessarily represent the view of the Minister for Education or the Australian Government. The Australian Government does not give any warranty nor accept any liability in relation to the contents of this work. © Commonwealth of Australia 2011 AURT 3046666 A Repair and replace emission control systems