Block B – Engine And Supporting Systems

Trends

Due to federal mandates on reducing emissions, engine and supporting systems are becoming more sophisticated and complex. For example, alternate fuel systems such as liquid natural gas and hybrid drive are becoming more prevalent.

Electronically controlled engines and supporting systems are more commonly used throughout the industry. Therefore, truck and transport mechanics need better computer skills and electronic diagnostic abilities. They service, diagnose and repair various types of systems with increasing complexity and quickly changing technology.

Related Components (including, but not limited to)

Base engine: pistons, piston rings, wrist pins, connecting rods, flywheels, vibration dampers/harmonic balancers, timing gears, crankshaft, camshafts, valve/injector trains, rocker assemblies, engine cylinder block, wet liner/sleeve, dry sleeve, cylinder head, intake manifold, exhaust manifold, oil pans/sumps.

Engine management system: Electronic control modules (ECMs), sensors, solenoids, harnesses, actuators, connectors, potentiometers, vehicle electronic control units (VECUs).

Cooling system: radiator, radiator cap, coolant pumps, temperature gauge, thermostats, cooling fans, fan shroud, fan belt and pulleys, hoses.

Lubrication system: sump/oil pan, dipstick, oil pumps, pressure regulating valves, filters, filter bypass valves, oil coolers, relief valves, bypass valves.

Fuel delivery system: injectors, tanks, check valves, lines, injection pumps, lift pumps.

Intake/exhaust system: air cleaners, charge air coolers (CACs), turbo chargers, exhaust manifold, exhaust piping, intake piping, mufflers, hoses, emergency shutdown devices.

Starting aids: pre-heaters, ether injectors, auxiliary heaters, glow plugs.

Emission system: catalytic converters, exhaust gas recirculation systems (EGR), particulate filters, after treatment regeneration devices (ARDs), diesel exhaust fluid (DEF) systems, selective catalyst reduction (SCR) systems, diesel particulate filter (DPF) systems, crankcase ventilation systems and evaporative emission systems.

Tools and Equipment

See Appendix A.

Task 4 Services, diagnoses and repairs base engine.

Context

The engine produces power through engine speed and torque to enable movement of the vehicle. Truck and transport mechanics must diagnose and service the base engine and its components to ensure proper engine function and reduce down time.

Servicing includes the adjustment of components as well as their routine maintenance. Diagnosing is required to locate failures in order to effectively perform repairs on the engine, which may include replacement or rebuilding of components.

Required Knowledge

• K 1 base engine operating principles
• K 2 base engine components such as blocks, crankshafts, camshafts, cylinder heads, pistons and bushings
• K 3 cylinder head components such as valves, seats, springs and rockers
• K 4 troubleshooting trees and techniques
• K 5 specialty tools such as manometers, dynamometers, piston ring compressors, dial indicators and torque wrenches, and their applications and operation
• K 6 certification requirements for road testing
• K 7 related symptoms of component failures such as abnormal vibration and noise
• K 8 oil sampling procedures
• K 9 inspection and testing procedures
• K 10 removal, replacement and repair procedures
• K 11 common causes and related symptoms of base engine failures such as oil contamination, overheating, over revving and operator misuse
• K 12 hazards associated with base engine such as sharp edges, weight and size
• K 13 safe work practices related to base engine hazards and associated jurisdictional safety regulations

Sub-task - B-4.01 Services base engine.

Key Competencies

• B-4.01.01 collect oil sample according to sample kit instructions
• B-4.01.02 visually inspect oil sample for residual contaminants and send sample for analysis according to employer practices and customer request
• B-4.01.03 visually inspect upper cylinder head for worn, damaged or defective components such as chipped or worn cam lobes, broken valve springs and damaged rocker arms
• B-4.01.04 adjust clearance of valve train components according to manufacturers’ specifications
• B-4.01.05 record service information and inspection findings according to manufacturers’ requirements for warranty, and for future reference and tracking

Sub-task - B-4.02 Diagnoses base engine.

Key Competencies

• B-4.02.01 obtain details of symptoms associated with complaint to establish a starting point for diagnostics
• B-4.02.02 perform sensory inspections such as feeling for vibrations, listening for abnormal sounds and smelling for burning oil to confirm complaint and establish a preliminary diagnosis
• B-4.02.03 perform diagnostic procedure by following troubleshooting tree or schematic supplied by manufacturer to determine failure
• B-4.02.04 perform specialized testing procedures such as testing for excessive crankcase pressure to assess components for wear, damage or defects using tools and equipment such as manometers
• B-4.02.05 interpret oil sample analysis results to determine specific component wear
• B-4.02.06 compare test results to manufacturers’ specifications or expected values to verify diagnosis
• B-4.02.07 perform failure analysis to determine root cause of failure
• B-4.02.08 record test results and inspection findings according to manufacturers’ requirements for warranty, and for future reference and tracking

Sub-task - B-4.03 Repairs base engine.

Key Competencies

• B-4.03.01 remove and replace worn, damaged or faulty components such as worn bearings, worn piston rings, and scored or cavitated liners
• B-4.03.02 perform updates according to manufacturers’ specifications
• B-4.03.03 rebuild cylinder head by cleaning, replacing worn parts such as valves, seats and springs according to manufacturers’ specifications
• B-4.03.04 rebuild base engine by cleaning, replacing worn or damaged components such as scored or loose liners, cracked block and broken crankshaft
• B-4.03.05 repair base engine using methods such as replacing parts causing the failure, grinding valves, shimming cylinder liners and using oversized bearings, according to manufacturers’ specifications
• B-4.03.06 perform adjustment procedures such as adjusting valve train clearances to ensure proper operation of component/equipment
• B-4.03.07 verify repairs using methods such as road testing and dynamometer testing
• B-4.03.08 document that repairs and verifications have been performed for warranty, liability, future reference and tracking

Task 5 Services, diagnoses and repairs lubrication systems.

Context

The lubrication system regulates the flow of oil throughout the engine and its components to the liquid-to-liquid cooler to transfer heat from the oil to the cooling system. It also flushes contaminants away from engine components through the oil filter. Its main purpose is to protect internal engine components by creating a thin film of oil between metal surfaces.

Truck and transport mechanics must service and troubleshoot the lubrication system to ensure proper protection of the engine and its components.

Servicing includes the replacement of consumables as well as the routine maintenance of the system. Diagnosing is required to determine root cause of failures in order to effectively perform repairs on lubrication system.

Required Knowledge

• K 1 lubrication system operating principles
• K 2 lubrication system components such as oil pumps, filters and coolers
• K 3 inspection and testing procedures
• K 4 troubleshooting trees and techniques
• K 5 specialty tools such as pressure gauges and infrared/direct contact thermometers
• K 6 related effect of component failure such as engine knock, excessive engine temperature and loss of oil pressure
• K 7 removal, replacement and repair procedures
• K 8 hazards of working with lubrication systems such as high temperatures and skin irritation
• K 9 specialized tools such as pressure, temperature and feeler gauges
• K 10 lubrication flow schematics
• K 11 lubrication system consumables such oil and filters

Sub-task - B-5.01 Services lubrication system.

Key Competencies

• B-5.01.01 clean lubrication system components using lint-free rags and solvents
• B-5.01.02 perform sensory inspections such as looking for leaks, smelling for burnt oil and checking magnetic drain plug for contamination
• B-5.01.03 measure oil pressure, temperature and level to determine if they meet manufacturers’ specifications
• B-5.01.04 remove and replace consumables such as oil filter and oil according manufacturers’ maintenance schedule and specifications
• B-5.01.05 recycle and/or dispose of consumables according to jurisdictional regulations
• B-5.01.06 record service information and inspection findings according to manufacturers’ requirements for warranty, and for future reference and tracking

Sub-task - B-5.02 Diagnoses lubrication system.

Key Competencies

• B-5.02.01 obtain details of symptoms associated with complaint to establish a starting point for diagnostics
• B-5.02.02 perform sensory inspections such as listening for engine knock, smelling for burnt oil and looking for leaks to confirm complaint and establish a preliminary diagnosis
• B-5.02.03 perform diagnostic procedure by following troubleshooting tree or schematic supplied by manufacturer to determine failure
• B-5.02.04 perform specialized testing procedures such as oil pressure and temperature, pump cavitation and aeration (pseudo cavitation)
• B-5.02.05 compare test results to manufacturers’ specifications or expected values to verify diagnosis
• B-5.02.06 perform failure analysis to determine root cause of failure
• B-5.02.07 record test results and inspection findings according to manufacturers’ requirements for warranty, and for future reference and tracking

Sub-task - B-5.03 Repairs lubrication system.

Key Competencies

• B-5.03.01 remove and replace worn, damaged or faulty components such as defective pumps, faulty oil thermostats and broken or plugged piston cooling nozzles
• B-5.03.02 verify repair by using methods such as checking oil pressure and temperature while running engine at operating condition
• B-5.03.03 document that repairs and verifications have been performed for warranty, liability, future reference and tracking

Task 6 Services, diagnoses and repairs intake and exhaust systems

Context

The engine intake and exhaust systems supply cool filtered air to the engine and releases exhaust gases to the atmosphere after combustion. Emissions control systems are often an integral part of both intake and exhaust systems.

Truck and transport mechanics must service, diagnose and repair the intake and exhaust systems to ensure proper operation and performance of the engine.

Servicing includes the replacement of consumables and components as well as their routine maintenance. Diagnosing is required to determine root cause of failures in order to effectively perform repairs on intake and exhaust systems.

Required Knowledge

• K 1 intake and exhaust systems operating principles
• K 2 intake system components and consumables such as CACs, turbochargers, piping, gaskets and filters
• K 3 starting aids such as pre-heaters and ether injection
• K 4 exhaust system components such as manifolds, piping and mufflers
• K 5 types and arrangement of turbochargers such as variable geometry turbochargers (VGTs) and compound turbochargers
• K 6 specialized tests such as boost test, exhaust leakage test, VGT actuator test, and intake and CAC pressure test
• K 7 specialized tools such as manufacturers’ software, intake CAC pressure test kits and manometers
• K 8 recycling and disposal methods, and jurisdictional requirements
• K 9 troubleshooting trees and techniques
• K 10 intake system contamination such as dust, oil and antifreeze
• K 11 inspection and testing procedures
• K 12 common causes and related symptoms of component failures such as black exhaust smoke, poor engine performance and no start
• K 13 hazards associated with intake and exhaust systems such as running engine in confined spaces, extreme heat from exhaust components and dangers surrounding air inlets
• K 14 emergency shutdown devices such as air dams (cable and switch operated)
• K 15 safe work practices related to fuel delivery system hazards and associated jurisdictional regulations

Sub-task - B-6.01 Services intake and exhaust systems.

Key Competencies

• B-6.01.01 clean intake components
• B-6.01.02 perform sensory inspections of intake and exhaust systems to identify worn, damaged or defective components such as looking for soot deposits indicating leaks, listening for air escaping and looking for incorrect fit or installation of piping
• B-6.01.03 remove and replace consumables according to manufacturers’ specifications and maintenance schedule
• B-6.01.04 recycle and/or dispose of consumables according to jurisdictional regulations
• B-6.01.05 record service information and inspection findings according to manufacturers’ requirements for warranty, and for future reference and tracking

Sub-task - B-6.02 Diagnoses intake and exhaust systems.

Key Competencies

• B-6.02.01 obtain details of symptoms associated with complaint to establish a starting point for diagnostics
• B-6.02.02 perform sensory inspections to confirm complaint and establish a preliminary diagnosis
• B-6.02.03 perform diagnostic procedure by following troubleshooting tree or schematic supplied by manufacturer to determine failure
• B-6.02.04 perform specialized testing procedures on exhaust system such as turbocharger actuator test and CAC pressure drop test to assess components for wear, damage or defects
• B-6.02.05 perform specialized testing procedures on exhaust system such as back pressure exhaust test to assess components for wear, damage or defects
• B-6.02.06 compare test results to manufacturers’ specifications or expected values to verify diagnosis
• B-6.02.07 perform failure analysis to determine root cause of failure
• B-6.02.08 record test results and inspection findings according to manufacturers’ requirements for warranty, and for future reference and tracking

Sub-task - B-6.03 Repairs intake and exhaust systems.

Key Competencies

• B-6.03.01 remove and replace worn, damaged or faulty components such as cracked intake manifold or CAC, corroded piping and damaged turbocharger seals
• B-6.03.02 remove and replace worn, damaged or faulty starting aid components
• B-6.03.03 use welding and cutting equipment to repair piping, remove broken fasteners, and cut and weld intake and exhaust piping
• B-6.03.04 perform adjustment procedures such as calibrating turbocharger actuator to ensure proper operation of component/equipment
• B-6.03.05 verify repairs using methods such as pressure testing intake system and performing sensory observations of exhaust system
• B-6.03.06 document that repairs and verifications have been performed for warranty, liability, future reference and tracking

Task 7 Services, diagnoses and repairs engine management system.

Context

Engine management systems receive analog/digital inputs and distribute analog/digital outputs to many components throughout the vehicle to optimize vehicle performance.

Truck and transport mechanics must service and diagnose the engine management system to ensure proper operation of multiple components of the vehicle.

Servicing includes the replacement of components as well as software updates. Diagnosing is required to determine root cause of failures in order to effectively perform repairs on engine management systems.

Required Knowledge

• K 1 engine management system operating principles
• K 2 characteristics of manufacturer specific management systems
• K 3 engine management system components such as harnesses, ECMs, VECUs, switches, sensors and actuators
• K 4 servicing procedures for engine management systems
• K 5 effect of static electricity and external voltage induction on delicate electronic components
• K 6 hazards when servicing engine management systems such as high voltage outputs
• K 7 troubleshooting trees and techniques
• K 8 specialized tools such as computers, multimeters and break-out harnesses
• K 9 types of specialized connectors and harnesses such as sensor connections, injector harnesses and ECM connectors
• K 10 common causes and related symptoms of failures such as poor connections, chaffed or corroded harnesses and poor repair practices causing poor performance and fault codes
• K 11 safe work practices related to engine management system hazards and jurisdictional safety regulations
• K 12 removal, replacement and repair procedures
• K 13 inspection and testing procedures
• K 14 specialized tests such as computer-based testing based on manufacturers’ recommendations
• K 15 wiring schematics

Sub-task - B-7.01 Services engine management system.

Key Competencies

• B-7.01.01 adjust ECM parameters such as shutdowns, cruise controls and fan controls
• B-7.01.02 perform engine management system software updates
• B-7.01.03 download engine management system logged data

Sub-task - B-7.02 Diagnoses engine management system.

Key Competencies

• B-7.02.01 obtain details of symptoms associated with complaint to establish a starting point for diagnostics
• B-7.02.02 perform sensory inspections to confirm complaint and establish a preliminary diagnosis
• B-7.02.03 perform diagnostic procedure by following troubleshooting tree or schematic supplied by manufacturer to determine failure
• B-7.02.04 perform specialized testing procedures such as fault code retrieval, resistance test, voltage drop test and commanded actuator test using tools and equipment such as computers, multimeters, pin-out equipment and break-out harnesses
• B-7.02.05 compare test results to manufacturers’ specifications or expected values to verify diagnosis
• B-7.02.06 perform failure analysis to determine root cause of failure
• B-7.02.07 record test results and inspection findings according to manufacturers’ requirements for warranty, and for future reference and tracking

Sub-task - B-7.03 Repairs engine management system.

Key Competencies

• B-7.03.01 remove and replace damaged or faulty components such as faulty ECMs, chaffed harnesses and open/shorted sensors or actuators
• B-7.03.02 perform updates according to manufacturers’ specifications
• B-7.03.03 repair components such as harnesses and connections by soldering, splicing and crimping, according to manufacturers’ specifications
• B-7.03.04 calibrate engine management components such as injectors, turbochargers and speed control sensors
• B-7.03.05 verify repair by using methods such as verifying that fault codes remain inactive and performing operational tests
• B-7.03.06 document that repairs and verifications have been performed for warranty, liability, future reference and tracking

Task 8 Services, diagnoses and repairs fuel delivery system.

Context

The fuel delivery system supplies clean fuel to the engine at regulated pressure and volume.

Truck and transport mechanics must service, diagnose and repair the fuel delivery system to ensure proper engine operation and minimize downtime.

Required Knowledge

• K 1 fuel system operating principles
• K 2 types of fuel delivery systems such as mechanical and electronic
• K 3 fuel delivery system components such as pumps, injectors, tanks, check valves, fuel regulating valves and lines
• K 4 fuel delivery system consumables such as fuels, filters and fuel-water separators
• K 5 controls such as ECMs and electronic controls
• K 6 types of fuels such as winter and summer fuels, natural gas, propane, diesel and biodiesel
• K 7 types of fuel additives and their purpose such as cetane boost and antigel/antiwax
• K 8 troubleshooting trees and techniques
• K 9 specialty tools such as pressure gauges, vacuum gauges, fitting adaptors and injector removal/installation tools
• K 10 common causes and related symptoms of component failures such as exhaust smoke, rough running engine, poor engine performance and no start
• K 11 hazards associated with fuel delivery systems such as stored high pressure, irritant, flammability and noxious fumes
• K 12 safe work practices related to fuel delivery system hazards and associated jurisdictional regulations
• K 13 removal, replacement and repair procedures
• K 14 inspection and testing procedures
• K 15 fuel sampling procedures
• K 16 specialized tests such as pressure test, pressure decay test, injector leakage test and pump inlet restriction test
• K 17 recycling and disposal methods and jurisdictional requirements
• K 18 fuel flow schematics

Sub-task - B-8.01 Services fuel delivery system.

Key Competencies

• B-8.01.01 clean fuel delivery system components using lint-free rags and solvents
• B-8.01.02 perform sensory inspections such as smelling or looking for fuel leaks, looking for excessive exhaust smoke and listening for engine miss
• B-8.01.03 remove and replace consumables according manufacturers’ maintenance schedule and specifications
• B-8.01.04 recycle and/or dispose of consumables according to jurisdictional regulations
• B-8.01.05 record service information and inspection findings according to manufacturers’ requirements for warranty, and for future reference and tracking

Sub-task - B-8.02 Diagnoses fuel delivery system.

Key Competencies

• B-8.02.01 obtain details of symptoms associated with complaint to establish a starting point for diagnostics
• B-8.02.02 perform sensory inspections such as smelling and looking for leaks, listening for poor engine performance and looking for excessive exhaust smoke to confirm complaint and establish a preliminary diagnosis
• B-8.02.03 perform diagnostic procedure by following troubleshooting tree or schematic supplied by manufacturer to determine failure
• B-8.02.04 perform specialized testing procedures to assess components for wear, damage or defects using manufacturer’s recommended tools and equipment, and following jurisdictional safety guidelines
• B-8.02.05 compare test results to manufacturers’ specifications or expected values to verify diagnosis
• B-8.02.06 perform failure analysis to determine root cause of failure
• B-8.02.07 record test results and inspection findings according to manufacturers’ requirements for warranty, and for future reference and tracking
• B-8.02.08 interpret fuel system flow schematics

Sub-task - B-8.03 Repairs fuel delivery system.

Key Competencies

• B-8.03.01 remove and replace worn, damaged or faulty components such as leaking injectors, worn pumps and plugged lines
• B-8.03.02 perform updates according to manufacturers’ specifications
• B-8.03.03 perform measurements such as injector height, fuel pressure and pump inlet restriction to determine if they meet manufacturers’ specifications
• B-8.03.04 repair fuel delivery system by replacing or cleaning parts causing the failure and adjusting ECM parameters, according to manufacturers’ specifications
• B-8.03.05 perform adjustment procedures such as setting injector height and setting pump timing according to manufacturers’ specifications, to ensure proper operation of component/equipment
• B-8.03.06 verify repair using methods such as running equipment at operating condition and performing manufacturers’ test procedures
• B-8.03.07 document that repairs and verifications have been performed for warranty, liability, future reference and tracking

Task 9 Services, diagnoses and repairs emission systems for diesel engines.

Context

Engine emission systems work in conjunction with other engine systems to reduce nitric oxide and nitrogen dioxide (NOx gases) and other harmful by-products of combustion to meet jurisdictional environmental requirements.

Truck and transport mechanics must service and diagnose the emissions system to ensure proper operation and performance of the engine, and to ensure emissions levels meet requirements.

Servicing includes the replacement of consumables and components as well as their routine maintenance. Diagnosing is required to determine root cause of failures in order to effectively perform repairs on emissions systems.

Required Knowledge

• K 1 emission system operating principles
• K 2 types of emission systems such as EGR, SCR, DPF, DEF and crankcase ventilation systems
• K 3 emission system components and consumables such as oxidation catalysts, particulate filters, DEF, dosing nozzles, and EGR valves and coolers
• K 4 controls such as ECMs, and electronic and manual switches
• K 5 servicing procedures for emission systems
• K 6 effects of fuel additives
• K 7 troubleshooting trees and techniques
• K 8 specialty tools such as manufacturers’ software and temperature measurement devices
• K 9 common causes and related symptoms of component failures such as soot build-up, excessive heat in the EGR, high urea concentration and contamination in DEF
• K 10 hazards associated with emission systems such as skin and eye irritation, and high temperature
• K 11 safe work practices related to emission system hazards and associated jurisdictional regulations
• K 12 removal, replacement and repair procedures
• K 13 inspection and testing procedures
• K 14 specialized tests such as computer-based testing based on manufacturers’ recommendations
• K 15 recycling and disposal methods and jurisdictional requirements
• K 16 wiring schematics

Sub-task - B-9.01 Services emission systems for diesel engines.

Key Competencies

• B-9.01.01 clean emission system components such as DPF and fluid dosing nozzles
• B-9.01.02 perform sensory inspections of emission systems such looking for leaks, observing DEF levels and looking for accumulation of urea crystals
• B-9.01.03 perform software updates according to manufacturers’ recommendations
• B-9.01.04 remove and replace consumables and components according to manufacturers’ specifications and maintenance schedule B-9.01.05 recycle and/or dispose of consumables and components according to jurisdictional regulations
• B-9.01.06 record service information and inspection findings according to manufacturers’ requirements for warranty, and for future reference and tracking

Sub-task - B-9.02 Diagnoses emission systems for diesel engines.

Key Competencies

• B-9.02.01 obtain details of symptoms associated with complaint to establish a starting point for diagnostics
• B-9.02.02 perform sensory inspections to confirm complaints and establish a preliminary diagnosis
• B-9.02.03 perform diagnostic procedure by following troubleshooting tree or schematic supplied by manufacturer to determine failure
• B-9.02.04 perform specialized testing procedures such as computer-based testing to assess components for wear, damage or defects
• B-9.02.05 compare test results to manufacturers’ specifications or expected values to verify diagnosis
• B-9.02.06 perform failure analysis to determine root cause of failure
• B-9.02.07 record test results and inspection findings according to manufacturers’ requirements for warranty, and for future reference and tracking

Sub-task - B-9.03 Repairs emission systems for diesel engines.

Key Competencies

• B-9.03.01 release stored energy using any means necessary without releasing fluid from system
• B-9.03.02 remove and replace worn, damaged or faulty components such DPF, EGR, cooler and piping, and leaking dosing nozzles
• B-9.03.03 perform computer-based updates according to manufacturers’ recommendations
• B-9.03.04 reprogram parameters after repair according to manufacturers’ recommendations
• B-9.03.05 verify repair by using methods such as operating vehicle, parked regeneration and monitoring operation
• B-9.03.06 document that repairs and verifications have been performed for warranty, liability, future reference and tracking

Task 10 Services, diagnoses and repairs engine retarder systems.

Context

Engine retarder systems are an optional component used to assist the primary braking system to slow the vehicle and to prolong primary brake life.

These systems receive inputs from the vehicle and operator to determine appropriate timing to manage compression within the engine by controlling exhaust flow or valve position.

Truck and transport mechanics must diagnose and service/repair engine retarder systems to ensure proper function and reduce down time.

Required Knowledge

• K 1 engine retarder system operating principles
• K 2 function of electronic controls used with engine retarder systems
• K 3 types of engine retarder systems such as compression and exhaust
• K 4 engine retarder system components such as ECMs, solenoids, valves and switches
• K 5 inspection and testing procedures
• K 6 troubleshooting trees and techniques
• K 7 specialty tools such as computer-based manufacturers’ software, pressure testing equipment and multimeter
• K 8 specialized tests such as oil pressure tests, solenoid tests and electrical resistance tests
• K 9 hazards of working with engine retarder systems such as high temperatures and skin irritation
• K 10 safe work practices related to engine retarder system hazards and jurisdictional safety regulations
• K 11 related effect of component failure such as engine knock, excessive engine temperature and loss of oil pressure
• K 12 common faults associated with engine retarder systems such as intermittent operation and weak performance
• K 13 removal, replacement and repair procedures
• K 14 wiring schematics

Sub-task - B-10.01 Services and repairs engine retarder systems.

Key Competencies

• B-10.01.01 remove and replace worn, damaged or faulty components such as open/shorted solenoids, damaged O-rings and stuck exhaust valves
• B-10.01.02 perform ECM software updates according to manufacturers’ specifications
• B-10.01.03 repair components such as damaged harnesses, exhaust valves and slave pistons according to manufacturers’ specifications
• B-10.01.04 perform adjustment procedures such as valve clearances and parameters for operator preferences to ensure proper operation of component/equipment
• B-10.01.05 verify repair using methods such as road testing and function testing
• B-10.01.06 document that repairs and verifications have been performed for warranty, liability, future reference and tracking

Sub-task - B-10.02 Diagnoses engine retarder systems.

Key Competencies

• B-10.02.01 obtain details of symptoms associated with complaint to establish a starting point for diagnostics
• B-10.02.02 perform sensory inspections to confirm complaint and establish a preliminary diagnosis
• B-10.02.03 perform diagnostic procedure by following troubleshooting tree or schematic supplied by manufacturer to determine failure
• B-10.02.04 perform specialized testing procedures such as pressure tests, electrical resistance tests and commanded operational tests to assess components for wear, damage or defects
• B-10.02.05 compare test results to manufacturers’ specifications or expected values to verify diagnosis
• B-10.02.06 perform failure analysis to determine root cause of failure
• B-10.02.07 record test results and inspection findings according to manufacturers’ requirements for warranty, and for future reference and tracking

Task 11 Services, diagnoses and repairs cooling system.

Context

The cooling system regulates the circulation of coolant throughout the engine and other components to the air-to-liquid cooler to transfer heat from the engine to the atmosphere as well as the HVAC system.

Truck and transport mechanics must service and diagnose the cooling system to ensure proper operating temperature of the engine and function of the HVAC system.

Servicing includes the replacement of consumables and components as well as their routine maintenance. Diagnosing is required to determine root cause of failures in order to effectively perform repairs on cooling systems.

Required Knowledge

• K 1 cooling system operating principles
• K 2 cooling system components such as radiator caps, fans and belts
• K 3 coolant system consumables such as coolant filters and coolants
• K 4 types of coolants (conventional, extended life) and coolant additives
• K 5 coolant properties such as pH and freezing point
• K 6 sulphate and chloride levels in coolant
• K 7 purpose and operation of radiator cap
• K 8 common causes and related symptoms of component failures
• K 9 hazards associated with cooling systems such as pressure, steam and extreme heat
• K 10 safe work practices related to cooling system hazards and jurisdictional safety regulations
• K 11 specialized tests such as pressure test, supplemental coolant additives (SCA) test and dye test
• K 12 specialized tools such as belt tension gauges, refractometers and vacuum fill and degassing kits
• K 13 recycling and disposal methods, and jurisdictional requirements
• K 14 auxiliary heaters and heating components
• K 15 troubleshooting trees and techniques

Sub-task - B-11.01 Services cooling system.

Key Competencies

• B-11.01.01 flush cooling system according to manufacturers’ specifications and maintenance schedule
• B-11.01.02 visually inspect cooling system to identify problems such as improper speed of fan hub, cracked or missing fan blades, plugged radiators, damaged hoses, contamination in coolant, low coolant level and white exhaust
• B-11.01.03 adjust belt tension to manufacturers’ specifications
• B-11.01.04 measure coolant pH, sulphate and chloride levels to determine if they meet manufacturers’ specifications based on type of coolant
• B-11.01.05 test freezing point of coolant using refractometers, test strips and hydrometers
• B-11.01.06 release stored energy such as heat and pressure by allowing system to cool
• B-11.01.07 remove and replace consumables such as coolant filter and coolant according to manufacturers’ maintenance schedule and specifications
• B-11.01.08 recycle and/or dispose of consumables according to jurisdictional regulations
• B-11.01.09 record service information and inspection findings according to manufacturers’ requirements for warranty, and for future reference and tracking

Sub-task - B-11.02 Diagnoses cooling system.

Key Competencies

• B-11.02.01 obtain details of symptoms associated with complaint to establish a starting point for diagnostics
• B-11.02.02 perform sensory inspections such as looking for leaks, cracked hoses, smelling for coolant, feeling hoses for pliability and integrity, to confirm complaint and establish a preliminary diagnosis
• B-11.02.03 perform diagnostic procedure by following troubleshooting tree or schematic supplied by manufacturer to determine failure
• B-11.02.04 perform specialized testing procedures to assess system function such as correct operation of thermostat, water pump and fan hub using manufacturer’s recommended tools and equipment, and following jurisdictional safety guidelines
• B-11.02.05 pressure test radiator cap to rated pressure according to manufacturers’ specifications to ensure its proper operation
• B-11.02.06 compare test results to manufacturers’ specifications or expected values to verify diagnosis
• B-11.02.07 perform failure analysis to determine root cause of failure
• B-11.02.08 record test results and inspection findings according to manufacturers’ requirements for warranty, and for future reference and tracking

Sub-task - B-11.03 Repairs cooling system.

Key Competencies

• B-11.03.01 remove and replace worn, damaged or faulty components such as defective thermostats, worn pumps and degraded hoses
• B-11.03.02 rebuild components such as fan hubs by replacing parts according to manufacturers’ rebuild procedures
• B-11.03.03 adjust belt tension to ensure proper operation of fan and water pump
• B-11.03.04 verify repair by using methods such as road testing and pressure testing
• B-11.03.05 document that repairs and verifications have been performed for warranty, liability, future reference and tracking