TLIB707C - Carry Out Maintenance of Trailers - Learner Guide

8/14/2019 TLIB707C - Carry Out Maintenance of Trailers - Learner Guide

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TLIB707C Carryout maintenance

of trailers

Learner Guide


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Contents

What this Learners Guide is about........................................ 3

Planning your learning ........................................................... 4

How you will be assessed...................................................... 7

Section 1............................................................................................. 9

Inspect the suspension and axle, replace inner and outerbearings ................................................................................. 9

Section 2........................................................................................... 25

Inspect, adjust and make repairs to a trailer air brake system25

Section 3........................................................................................... 45

Carry out repairs to the electrical system of a commercialvehicle trailer ........................................................................ 45

Additional resources....................................................................... 53

Assessment tasks ........................................................................... 55

Feedback on activities .................................................................... 67

Training record information ........................................................... 71

Assessment checklist and record sheets ............................. 77

Training record sheet ............. Error! Bookmark not defined.


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TLIB707C Carry out maintenance of trailers

Page 2 Australian National Training Authority 2003ADELG1036 Customised and developed by Armstrongs Driver Education P/L July 2008


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Australian National Training Authority 2003 Page 3Customised and developed by Armstrongs Driver Education P/L July 2008 ADELG1036

What this Learners Guide is about

ThisLearnersGuideisabouttheskillsandknowledgerequiredtocarryoutbasicservicingandmaintenanceofacommercialtrailer,includingactiontoimplementthetrailermanufacturer'sspecificationsforroutinechecksandmaintenanceandtoensurethatallspecifiedsafetyrequirementsaremetandthatthetrailerisoperationaltotherequirementsofboththeworkplaceandtherelevantstate/territoryroadsandtrafficauthority.

TheElementsofCompetencyfromtheunitTLIB707CCarryoutmaintenanceoftrailerscoveredinthisLearnersGuidearelistedbelow.

Identifyfaultsandperformroutinemaintenance

Carryoutrepairsontrailers

Completedocumentation

ThisunitofcompetencyisfromtheTransportandLogisticsTrainingPackage(TLI07).


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Planning your learning

ItisimportanttoplanyourlearningbeforeyoustartbecauseyoumayalreadyhavesomeoftheknowledgeandskillsthatarecoveredinthisLearnersGuide.Thismightbebecause:

youhavebeenworkingintheindustryforsometime,and/or

youhavealreadycompletedtraininginthisarea.

Togetherwithyoursupervisorortrainerusethechecklistsonthefollowingpagestohelpyouplanyourstudyprogram.Youranswerstothequestionsinthechecklistwillhelpyouworkoutwhichsectionsof

thisLearnersGuideyouneedtocomplete.

ThisLearnersGuideiswrittenwiththeideathatlearningismademorerelevantwhenyou,thelearner,areactuallyworkingintheindustry.Thismeansthatyouwillhavepeoplewithintheenterprisewhocanshowyouthings,discusshowthingsaredoneandansweranyquestionsyouhave.Alsoyoucanpractisewhatyoulearnandseehowwhatyoulearnisappliedintheenterprise.

IfyouareworkingthroughthisLearnersGuideandhavenotyetfoundajobintheindustry,youwillneedtotalktoyourtraineraboutdoingworkexperienceorworkingandlearninginsomesortofsimulatedworkplace.


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Section 1: Inspect the suspension and axles,replace inner and outer bearings

Areyouableto: Yes No

1. identifyvariouscommercialvehicletrailersuspensiontypes?

2. performaserviceinspectiononacommercialvehicletrailersuspension?

3. performabasicserviceinspectiontoacommercialvehicletraileraxle?

4. replaceinnerandouterwheelbearingson

acommercialvehicletrailer?

Section 2: Inspect, adjust and make repairs to atrailer air brake system


1. outlinethefundamentalsofcompressedairbrakes?

2. correctlyidentifynominatedtrailerbrakecomponents?

3. correctlydiagnoseacommonairbrakefaultonacommercialvehicletrailer?

4. carryoutabrakeadjustmenttoacommercialvehicletrailer?

5. repairanairleakinatrailerairbrakesystem?


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Section 3: Carry out repairs to the electricalsystem of a commercial vehicletrailer


1. traceaselectedwiringcircuitonacommercialvehicletrailerandcheckforcontinuity?

2. repairadamagedsectionofwiringonacommercialvehicletrailer?

3. replacethebulbonacommercialvehicle

trailerindicatorlamp,clearancelampandanumberplatelight?

4. re-wireamaleelectricalplugonacommercialvehicletrailer?


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How you will be assessed

AssessmentofthisUnitofCompetencywillincludeobservationofrealorsimulatedworkprocessesusingworkplaceproceduresandquestioningonunderpinningknowledgeandskills.Itmustbedemonstratedinanactualorsimulatedworksituationundersupervision.

Youwillberequiredto:

undertakeacheckoftrailersuspension

changeawheelontrailer

replaceafaultyglobeontrailer

replacealensontrailer.


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Section 1

Inspect the suspension and axle,replace inner and outer bearings


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Section outline

Areascoveredinthissection

Identifyvariouscommercialvehicletrailersuspensiontypes

Performaserviceinspectiononacommercialvehicletrailersuspension

Performabasicserviceinspectiontoacommercialvehicletraileraxle

Replaceinnerandouterwheelbearingsonacommercialvehicletrailer


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Trailer suspension

Therearevarioustypesoftrailersuspension.Someoftheseare:

taperedsingleleafspring

taperedtriplesingleleafspring

overslungandunderslungleafsprings

two-stagemultileafspring

lastospherespringusedasaboosterspring

rubberloadcushionsuspension

rubbershearspringsuspensionstabilairerearaxleair

suspension.

(a)Taperedsingle-leafspring (b)Taperedtriplesingle-leafspring.


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Schematicviewofatwo-stagemultileafspringintheunloadedstage


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Lastospherespringusedasaboosterspring

Sectionalviewofarubberloadcushionsuspension

Rubbershearspringsuspension


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Activity 1: What type of suspension does your trailer have?

What type of suspension is your trailer equipped with?

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Activity 2: Carry out a trailer suspension inspection on yourtrailer

Carry out a trailer suspension inspection on your trailer. Onlycomplete the type of suspension that applies to your vehicle. Askyour trainer for feedback on your performance.

Is the equipment in good condition? Yes No

Leaf spring suspension check the:

leaf springs:

broken

misaligned

location bolts:

broken misaligned

U-bolts:

tight

not broken or rusted

suspension bushes:

worn

damaged

spring hangers:

check their security.

Is the equipment in good condition? Yes No

Rubber suspension check the:

rubber cushion:

security

condition

drive pin bushing:

security

condition

U-bolts:

tight not worn

not broken or rusted.


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Air suspension check the:

arm pivot nuts:

tight not worn

air spring nuts (top):

tight not worn

air spring nuts (bottom):

tight not worn

shock absorber nuts:

tight not worn

air springs condition

air spring and suspension pipework:

not leaking

nor creased or damaged

U-bolts

tight not worn

not broken or rusted.

Ask your trainer for feedback on your inspection.


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Remove and replace hub oil seal on your traileraxle

Huboilseal

1. Removal:

cagethespringbrakeadjacenttothehubtoberemovedandapplytheparkingbrake

usingasuitablejackundertheaxle,raisethetraileruntilthewheelsareclearofthegroundandsupporttheaxleonsafetystands

usingcorrecttoolremovethehubcapandO-ringanddiscardtheO-ring(orremovehubcapboltsandnuts)

positionawheeltrolleyjackunderthewheelsandsupporttheweight,thenstraightenthelocktabsonthelockwasherandremovethelocknutusingthecorrecttool(orremovesplitpininaxlenut)

removethelockwasher,thenusingthecorrecttoolremovetheadjustingnut

removetheouterwheelbearing,thenremovethewheelhubandbrakedrumfromtheaxleshaft

removetheinnerwheelbearingfromtheaxleshaftthen,usingahammer,taptheoilsealfromtheaxleshaft;discardtheoilseal

usingasuitabledrift(tool),removetheinnerandouterwheelbearingcups(onlyremovecupsifbearingsaretobereplaced).

2. Installation(alwaysreplacebearingcupsasapair).

thoroughlycleanthehubassemblyandtheaxleshaft,then

usingasuitabledrift,installtheinnerandouterbearingcupsintothehub.

lubricatetheoutersurfaceoftheoilsealandpositionthesealontheaxleshaft,ensuringthatthesidemarkedOilSidefacesawayfromthetrailer;onsomeaxlesbearingsmustbelocatedintohubsbeforesealisreplaced.


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Axle assembly - exploded view

Axleassembly-explodedview

Oilsealinstallation

Usingthefabricatedsealinstaller,seatthesealagainsttheaxleflange.

NOTE:Thewheelbearingsarefullyfloatingontheaxleshaft.

Installtheinnerwheelbearingontheaxleshaft(orintothehub

thenthesealonsometypes),thenusingawheeltrolleyjack,positionthebrakedrum,hubandwheelsontheaxleshaft.

Installtheouterwheelbearingandtheadjustingnut.Whilerotatingthewheels,tightenthenutusingthecorrecttooltoseatthebearingsandtheoilsealinthehub.

Backofftheadjustingnutcounter-clockwiseapproximately60degreesuntilthewheelsrotatefreely.Checkworkshopmanualformanufacturersspecifications.

Installthelockwasherandlocknut,thenbendthelocktabstosecuretheadjustingnutandthelocknut.

InstallanewO-ringonthehubcap,lubricatetheO-ringandthehubcapthreadstheninstallthecapandtightensecurelyusingthecorrecttool.

Raisetheaxleandremovethesafetystands.

Fillthehubcapandhubcavitywithasuitableoiltothelevel

indicatedonthecap.


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Hubcapoillevelindicator

Releasetheparkingbrakeanduncagethespringbrake.

Remove, check, repack and replace and adjustwheel bearing on trailer

Trailerwheelbearingadjustment

Wheelbearingsmustbecorrectlyadjustedandproperlylubricatedatregularintervalstoachievemaximumbearinglife,preventdamagetohubs,axelsandprobablythetrailer.Changingthewheelbearinglubricantisrecommendedevery50,000km,dependingonvehicle

speed,loads,andgeneraloperatingconditions.Proceedasfollowswhenchanginglubricantandinspectingbearings:

1. Removewheelassemblyandbearingconesfromaxlespindle.Cleanalloldlubricantfromhub,bearings,andhubcapwithagoodgradecommercialcleanerandstiffbrush,NOTSTEEL.DONOTuseairhoseincleaningoperation.Avoidspinningconewhilecleaning.

2. Wipethecleanedpartsdrywithcleanabsorbentclothorpaper.Cleananddryhandsandalltoolsusedintheservice

operation.Lubricantwillnotadheretoasurfacewhichiswetwithsolvent,andthesolventmaydilutethelubricant.CLEANLINESSISMOSTIMPORTANT.

3. Inspectseals,sealwipingsurfaces,bearingcups,andbearingconesforwearordamage.Handleallpartscarefullyduringcleaning,inspection,andinstallationtopreventdamagetobearingcage,rollersandcone.

4. Checkbearingconeswithcupsforcorrectfitandnumber.Thebearing(cupandcone)MUSTMATE.

CAUTION:Alwaysusecorrectcupwithmatingcone,nevermixparts.

5. Greaselubricatedbearings-packthebearingwithapressurepackerifpossible,usinganapprovedlubricantofmediumconsistency.Ifapressurepackerisnotavailable,packbearingsbyhandbyforcingthegreaseintothecavitiesbetweentherollersandcagefromthelargerendofthecone.Coatinsidethehubcapwithalightcoatofgrease,topreventmoistureaccumulation.


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6. Besureairtankisdrainedandreleasebrakeshoessotherewillbenopossibilityofbrakeshoedraginterferingwithbearingadjustment.Assembleandadjustwheelbearingsasfollows:

a. Ifgreaseisused,fillthecavityofthehubbetweenthebearingcupstoalevelofthebearingcupdiameter(aspermanufacturersspecifications).

b. Determineinnercupnumberandinstallmatchingconeinwheel,thenchecktoseethattheconeisproperlyseatedinthecup.

c. Installoilorgreasesealasrecommendedbymanufacturer.

d. Installwheelonaxle,beingcarefulnottodamagethebearingcups,conesorseal.

e. Determineoutercupnumberandinstallmatchingcone,thenchecktoseethattheconeisproperlyseatedinthecup.

f. DOUBLENUTAXLE-Installwheelbearingadjustingnut.Screwadjustingnutagainstthebearingasthewheelisbeingrevolvedinbothdirections,toexpelexcesslubricantandinsureproperseatingofbearingrollers.

g. Itisrecommendedthatatorquewrenchbeusedassemblingoftheadjustingnut.Theadjustingnutshouldbetightenedtotorquerecommendedbytrailermanufacturer.Iftorque

wrenchisnotavailable,tightenadjustingnutwithabar3.0to4.0cminlengthpushingdownwithfullarmstrength(notbodyweight)whilerotatingthewheelinbothdirections.

h. Backoffadjustingnut2to21/2holesonthelockringor1/4ofaturn.

i. Installwheelbearinglockwasherandjamnutandtightentotorquerecommendedbytrailermanufacturer.Ifatorquewrenchisnotavailable,tightenjamnutwitha3.0to4.0cmbarwithafullbodyweight.Thewheelshouldrotateeasilybut

nothaveexcessiveplay.j. Checkfinalbearingadjustmentwithadialindicator.

Adjustmentshouldbemadetothetorquerecommendedbyyourtrailermanufacturersrecommendation.Ifadialindicatorisnotavailable,checkbearingadjustmentforplaybyusingprybarunderhubortyres.

k. Shouldbearingsbeimproperlyadjusted,repeatsectionsFtoI.

l. Installhubcapwithpropergasket.Torquetothemanufacturersrecommendationforthecapscrewsonthe

hubcap.


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m. Aftereachrun,visuallyinspectwheelsandbrakedrumsfordamageorleaks.Keepclosecheckonallmovingpartstoobtainmaximumlife.

Recordallroutinemaintenanceandrepairs

Routinemaintenanceandrepairsmustberecordedinaccordancewithcompanyprocedures.Majorrepairitemsshouldbeidentifiedandyourtraineradvisedofthese.


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Activity 3: Demonstrate to your trainer axle fault diagnosis

Demonstrate to your trainer your knowledge in fault diagnosis on

your trailer. Use the faults indicated in the example below, fill in thepossible causes.

Faults and their probable causes

Fault Cause

Hub running hot

Premature bearing failure

Damaged wheel studs/bolts

Broken axle beam


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Fault Cause

Excessive tyre wear

Brakes binding

Inefficient brakes

There is feedback on this activity at the back of this LearnersGuide.


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Section 2

Inspect, adjust and make repairsto a trailer air brake system


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Section outline

Areascoveredinthissection

Outlinethefundamentalsofcompressedairbrakes

Correctlyidentifynominatedtrailerairbrakecomponents

Correctlydiagnoseacommonairbrakefaultonacommercialvehicletrailer

Carryoutabrakeadjustmenttoacommercialvehicletrailer

Repairanairleakinatrailerbrakesystem


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The fundamentals of compressed air brakes

Componentsofcompressedairbrakes:

Compressor:

furnishesthecompressedairforbrakingoperationbytakingfreeairoratmosphereandcompressingit.

Reservoir:

thecompressedairpassesfromthecompressorintothereservoirwhereit(anditsenergy)arestoreduntilneeded.

Brakevalve:

thecompressedairisheldinthereservoiruntilreleasedbythedriveroperatingaircontrolvalves.

Servicebrakesystem:

whenthebrakevalveisoperatedbythedriver,airflowstothechamberswhereitsenergyistransformedintothemechanicalforceandmotionnecessarytoapplythebrakes.

Trailersystem


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Thefundamentalsofcompressedairbrakes


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Activity 4: Locate graph showing differences in brakingforces

Obtain from your manufacturers manual or a brake specialist agraph or table showing the differences in braking forcerequirements for vehicles and loads. Paste this below for yourreference.


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Air brake maintenance

Theairbrakesystemisthemostimportantsafetysystemonavehicle.

Yet,themaintenanceofthesystemisafairlysimplejob,capableofbeingperformedbyanymechanicwiththeuseofordinaryshoptools.Themaintenanceofthesystemcanbebrokendownintotwomajorareas:

pneumaticfactors

mechanicalfactors.

1. PneumaticFactors

Anidealbrakingsystemcanbedefinedasoneinwhichthebrakingpressurereacheseachactuatoratthesametimeandatthesamepressurelevel.Oneofthefactorsthataffectsthisperformanceistheselectionoftubingandhosesizes.Airapplicationandreleaseperformanceispartiallydependentuponthesizeandvolumeofchambers,vehicleweightsandlocationsofthevalvesandchambers,ordistancetheairmusttravel.Performanceisengineeredintothevehiclebythemanufacturer;theroleofthevehicleownerand/ormechanicistopreservethat

pneumaticperformance.

2. Tubing

Whenreplacingtubingorhose,alwaysreplacewiththesamesize.Thesesizeshavebeendeterminedbythevehiclemanufacturertoobtaindesiredperformance.Coppertubingshouldnotbeusedinthehydraulicsystem.Becarefullynottokinkorcrackthetubingwhenbendingtofittheframeorrearaxleforms.Makesuretubingandhoseareproperlysupported.

Repairingadamagedbraketube

Lineflaringsequence

1. Cutoffandstraightentherequiredlengthofonetube(atubingcuttertoolwillsimplifymakingacleanandsquarecut).

2. Squareofftheendsofthelinewithafile,andchamfertheendofthelinetobeflared.

3. Selectthesplitdieforthelinetobeusedandinsertthedieintothetaperedholeinthebody.


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4. Pushthetubethroughthedieuntilthelineisevenwiththefaceofthedie.Lockthelineinthispositionbytighteningthewingnutsecurely.

5. ThepunchesaremarkedOp.1andOp.2.Slidethefirst

operationpunchintotheholeinthecentreofthebodyandtightenthescrewsecurelytoformthesingleflare.

6. Releasethescrewandreplacethefirstoperationpunchwiththesecondpunchandtightenthescrewtoformthedoubleflare.

7. Releasethescrew,wingnut,punchanddies.

8. Removethelineandinspecttheflareforcracksorpoorflareform.Iftheflareisnotcorrect,cutitoffandrepeattheprocess.

9. Thefinishedflaremustbesquarewiththeline,freeofcracksandhaveasmoothmatingsurfacetoensurealeakproofconnection.

10.Repeatmaintenanceandrepairsinaccordancewithcompanyprocedures.


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Activity 5: Demonstrate for your trainer the repair andreplacement of a section of damaged brake line

Using a scrap piece of fuel line (or repair a leaking fuel line on yourvehicle), make a line flared joint. Ask your trainer for feedback onyour effort.


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Brakehose

Replaceaflexiblebrakehoseifitshowssignsofsoftening,crackingorotherdamage.

Wheninstallinganewbrakehose,positionthehosetoavoidcontactwithothervehicleparts.


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Activity 6: Replace a brake hose on your vehicle

Demonstrate for your trainer how you would replace a brake hoseon your vehicle. Ask your trainer for feedback on your performance.


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Brakewheelcylinder

Disassembly

1. Withthewheelcylinderremoved,removetherubberbootsfromtheendsofthebrakecylinder.Removethepistons,cups,andpistonreturnspringandpistonexpanderassemblyfromthecylinder.

2. Removethebleederscrewfromthecylinder.

Assembly

1. Coatallbrakecylinderpartswithcleanextraheavydutybrakefluidasrecommendedbythemanufacturersmanual.

2. Installthebleederscrewinthebrakecylinder.

3. Placethepistonreturnspringandpistonexpanderassembly,cups,andpistonsinthecylinderbore,andinstallabootandlinkovereachendofthecylinder.Clampthebrakecylinderpistonsagainsttheendsofthecylinder.Whenusingabrakecylinderrepairkitfollowtheinstructionsinthekitanduseallofthepartsprovided.

Replacebrakeshoesandadjustingmechanism

1. Raisethevehicleuntilthetyresclearthefloorandinstallsafetystands.Removethewheelandtireassembly.Removethedrumorthehubanddrumassembly.Markthehubanddrumtoaidassemblyinthesameposition.

2. Expelallvacuuminthesystembeforedisconnectingthehydrauliclines.Expelvacuuminthesystembypushingdownonbrakepedalwhenengineisoff.

3. Removetheshoeretractingspringsandhold-downC-clips.Liftofftheshoes.

4. Toremoveanautomaticadjusterfromtheshoe,unhookthewedgeactuatingcoilspringfromthewedge.Unhooktheleveractuatingspringfromtheshoeweb.Workthespringcoilofftheleverpivotpinandslidethespring`Uhookoffthecontactplug-leverpin.Pulltheadjusterleverfromtheoppositesideoftheshoeweb,contacttheplugthroughtheshoetableandliftoffthewedgewasher,wedgeandthewedgeguide.

Installation


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1. Toinstalltheadjusterassembly,positionthewedgeguidewithitspinintheholeprovidedinthebrakeshoe.Placethewedgeguideonthesideofthebrakeshoefarthestawayfromthecarrierplate.Positionthewedgeontheshoewebwithitsserratededgerestingagainsttheserrationsonthewedgeguidesotheslotisaligned

withtheleverpivotpinhole.

2. Insertthecontactplugfromthedrumsideoftheshoe,guidingitsshankthroughtheholeintheshoetableoverthewedgeandwedgeguide.

3. Inserttheadjusterleverpinsthroughtheshoewebfromtheoppositesideoftheshoe,guidingtheactuating(centre)pinintothematingholeofthecontactplugshank.Placethewedgewasherovertheshoulderofthepivotpin.

4. Slidethe`Uhookoftheadjusterspringonthepinoverthecontactplugshank.Attachtheendofthewedgeactuatingspringtothishook,theninstallthecoiloftheadjustertorsionspringoverthepivotpinandpullthespringhookovertheedgeofthewedge.

5. Connecttheotherendofthewedgespringtothehookofthewedge.

6. Fullyretractthewedgeagainsttheleverpivotpinbypressingthecontactplugtopermitthecontact.Iftheplugsticksoutmorethan

0.005.inchabovethelining,clampthebrakeshoeinavicesothevicejawsbearagainsttheadjusterleveranddressdowntheplug.Thiscanbedonewithafile,takingcarenottofileaflatspotonthelining.

7. Placetheshoeassemblies(correctshoes,usethemanufacturersspecification)onthecarrierplatewiththeshoehold-downstudsthroughtheovalshapedholeintheshoewebs.Placetheshoeassembliesonthewheelcylinders.

8. Installtheflatwashersandbowedwashers,andcrimptheC-washersonthehold-downstudstosecuretheshoes.

9. Installthebrakeshoeretractingspringswiththelongendhookedattheanchorendoftheshoe.Besuretheshoewebsareengagedinthewheelcylinderpistoninsertslots.

10.Installthehubanddrumassembly.

11. Adjustandbleedthebrakesasdescribedbelow.

12. Recordandreportmaintenanceandrepairsinaccordancewithcompanyprocedures.


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Hydraulicsystembleeding

Whenanypartofthehydraulicsystemhasbeendisconnectedforrepairorreplacement,airmaygetintothelinesandcausespongy

pedalaction.Thisrequiresthebleedingofthehydraulicsystemafterithasbeenproperlyconnectedtobesureallairisexpelledfromthebrakecylindersandlines.Thehydraulicsystemcanbebledmanuallyorwithpressurebleedingequipment.

Bleedonebrakecylinderatatime.Startbleedingontherightrearbrake,thentheleftrear.Aftercompleting,proceedtobleedtherightfrontbrake,thentheleftfront.KeepthemastercylinderreservoirfilledwiththespecifiedHeavyDutyBrakeFluidduringthebleedingoperation.Neverusebrakefluidwhichhasbeendrainedfromthe

hydraulicsystem.

Ifthehydraulicsystemisequippedwithaframemountedvacuumbooster,bleedthehydraulicsectionoftheboosterbeforebleedingtherestofthesystem.Onvehicleswithaframe-mountedboosterandsplithydraulicbrakesystem,bleedthetwoboosterslavecylindersfirst,thenagainafterbleedingallthewheelcylinders.Bleedthesystemwiththeengineoffandwithnovacuuminthesystem.Ifthebrakepedalisstillspongyafterthefirstbleeding,repeatthebleedingprocedure.

Bleedthehydraulicsectionofbrakelinebetweenthemastercylinderandthevacuumbooster,byattachingthedraintubetothebleederscrewattheendplateofthebooster(orthebleederscrewnearestthepowerchamber).Repeatthisprocedureattheotherbleederscrew,(ifequipped).

Beforeanyattemptismadetobleedthesplithydraulicbrakesystem,removethebrakelightwarningswitchfromthepressuredifferentialvalve.Failuretoremovetheswitchfromthevalvecouldresultinpossibledamagetotheswitchassembly.

Manualadjustment-withdrumsinstalled

Adjustthesingleanchorbrakebyturninganadjustingscrewlocatedbetweenthelowerendsoftheshoes.

1. Raisethetraileruntilthetyresclearthefloor.

2. Removethecoverfromtheadjustingholeatthebottomofthebrakebackingplate,andturntheadjustingscrewinsidetheholetoexpandthebrakeshoesuntiltheydragagainstthebrakedrum.


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3. Whentheshoesareagainstthedrum,loosentheadjustingscrewanadditional1.0to1.2notchessothatthedrumrotatesfreelywithoutdrag.Ifthedrumdoesnotrotatefreely,removethewheelanddrum,andblowoutanydustanddirtfromthelinings.Usingsandpaper,removeanyrustfromthepointswheretheshoes

touchthebackingplate.ApplyalightcoatingofMulti-PurposeLubricant.Donotgetthelubricantonthelinings.

4. Installthewheelanddrum,andadjusttheshoes.Installtheadjustingholecoveronthebrakebackingplate.

5. Checkandadjusttheotherthreebrakeassemblies.

6. Applythebrakes.Ifthepedaltravelsmorethanhalfwaytothefloor,thereistoomuchclearancebetweenthebrakeshoesand

thedrums.RepeatStep2and3above.

7. Whenallbrakeshoes,havebeenproperlyadjusted,lowerthevehicleandroadtesttocheckbrakeoperation.Performtheroadtestonlywhenthebrakeswillapplyandthevehiclecanbesafelystopped.


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Activity 7: Manually adjust your vehicle brakes

Demonstrate to your trainer the manual adjustment of your trailerbrakes.


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Brakeadjustment

Probablythemostimportantfactorinobtainingmaximummechanicaloutputofthechamberisproperbrakeadjustment.Allchamber

strokesshouldbeadjustedtoapproximatelythesamestroke,andtheadjustmentshouldbemadesothatthechamberstrokeisasshortaspossiblewithoutthebrakesdragging.Improperlyadjustedbrakeswasteairandleverage,andcontributetopoorbrakeperformance.

Inmanycases,complaintsofpoororinsufficientbrakescanbetakencareofbyproperbrakeadjustment.

Theimportanceofreservoirdraining

Thecontaminantsthatcollectinairbrakereservoirsconsistofwatercondensedfromtheairandasmallamountofoilfromthecompressor.Thiswaterandoilnormallypassintothereservoirintheformofvapourbecauseoftheheatgeneratedduringcompression.

Thereisprobablynomoresimpleyetmoreimportantmaintenancethanreservoirdraining.Allreservoirsnotequippedwithautomaticdrainingdevicesormoistureremovaldevicesshouldbedraineddaily.Allautomaticdrainvalvesandmoistureremovingdevicesshouldbecheckedperiodicallyforproperoperation.

Asthecomplexityoftheairbrakesystemhasincreased,sohastheneedforcleanair.Manyofthelaterdesignvalvescontainsmallorificesandpassagesand,thus,aremoresusceptibletocontaminants.Inaddition,thepreventionoffreeze-upsinthesystemisequallyimportant.ThedevelopmentoftheAirDrierhasbeenanimportantdevelopmentinprovidingclean,dryair,anditsuseishighlyrecommended.Alcoholevaporatorsalsoservethesystem,helpingtopreventfreeze-ups.

Caution notes for maintaining air brake systems

Whenworkingonoraroundairbrakesystemsandcomponents,thefollowingprecautionsshouldbeobserved.

1. Alwaysblockvehiclewheels.Stopenginewhenworkingunderavehicle.Depletingvehicleairsystempressuremaycausevehicletoroll.Keephandsawayfromchamberpushrodsandslackadjusters;theymayautomaticallyapplyassystempressuredrops.

2. Neverconnectordisconnectahoseorlinecontainingairpressure.Itmaywhipasairescapes.Neverremovea


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componentorpipeplugunlessyouarecertainallsystemspressurehasbeendepleted.

3. Neverexceedrecommendedairpressureandalwayswearsafetyglasseswhenworkingwithairpressure.Neverlook

intoairjetsordirectthematanyone.4. Neverattempttodisassembleacomponentuntilyouhave

readandunderstandrecommendedprocedures.Somecomponentscontainpowerfulsprings.Useonlypropertoolsandobserveallprecautionspertainingtouseofthosetools.

5. Useonlygenuinereplacementpartsandcomponents:

Onlycomponents,devicesmountingandattachinghardwarespecificallydesignedforuseinairbrakesystemsshouldbe

used. Replacementhardware,tubing,hose,fittings,etc.shouldbeof

equivalentsize,typelength,andstrengthastheoriginalequipment.

Makecertainthatwhenreplacingtubingorhose,allsupports,clampsorsuspendingdevicesthatwereoriginallyinstalledbythevehiclemanufacturerarereinstalled.

6. Deviceswithstrippedthreadsordamagedpartsshouldbereplaced.Repairsrequiringmachiningshouldnotbe

attempted.

Lubricationrecommendations

Theuseofproperlubricantsinaircomponentsisextremelyimportant.Lubricantsotherthanthoserecommendedbelowmaynotbecompatiblewithinternalpartsand,therefore,arenotrecommended.


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Activity 8: What is the correct lubrication?

From your manufacturers manual complete the table below. Fill inthe recommended lubricants for the named devices.

Devices Recommended lubricant

Metal to metal parts such astreadle rollers, pins, and linkage

DD-3., SD-3. slack adjuster

Compressor unloader

Standard slack adjuster

Automatic slack adjuster

All air brake control devices withrubber o-rings

Rotochamber and rotowedgediaphragms

DS-1. fan clutch (with greaseprovision)

Speak to your trainer about your responses for this activity.


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Activity 9: What is your manufacturers recommendation forbrake servicing?

What is the recommended brake maintenance recommended byyour manufacturer? Use the manufacturers manual to locate thisinformation.

____________________________________________________

____________________________________________________

____________________________________________________

____________________________________________________

____________________________________________________

____________________________________________________

Ask your trainer if this is a sufficient maintenance schedule for yourtrailer, taking into consideration the type of operation you perform.Write in your trainers comments below.

____________________________________________________

____________________________________________________

____________________________________________________

____________________________________________________

____________________________________________________

____________________________________________________


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Section 3

Carry out repairs to the electricalsystem of a commercial vehicletrailer


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Section outline

Areas covered in this section

Trace a selected wire circuit on a commercial trailer

Repair a damaged section of wiring on a commercial vehicle trailer

Replace the bulb on a commercial vehicle trailer indicator lamp, clearancelamp and a number plate light

Rewire a male electrical trailer plug on a commercial vehicle trailer


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Removing, rewiring and replacing electricalparts

Any attempt to drive your vehicle when a body electrical part has been

removed from its circuit may be dangerous and must be prevented by

correctly preparing your vehicle.

To prepare your vehicle for the removal and replacement of body

electrical parts:

park your vehicle on a flat level surface

select neutral and chock the wheels

apply the park brake

disconnect the battery.


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Activity 10: Rewire a male trailer plug on your vehicle

Re-wire a male electric trailer plug on your vehicle trailer.

Did the learner Yes No

1. Use the correct hand tools to remove coverfrom male plug to expose wiring?

2. Use a wiring diagram to show the standardwiring code, or did they draw a diagram,marking in the wiring colours and contactreferences?

3. Check the wiring ends before commencingthe re-wiring process, to make sure the wireswere clean and undamaged?

4. Rewire the male trailer plug making sure thewires matched the following?

left indicator:

yellow wire in No. 1.

auxiliary:

blue wire in No. 2.

earth:

white wire in No. 3.

right indicator:

green wire in No. 4.

auxiliary:

black wire in No. 5.

stop:

red wire in No. 6

tail, No. Plate and clearance:

brown wire in No. 7.

5. Replace the wiring cover, using the correcthand tool?

6. Check all the lights to make sure the re-wiring task was carried out correctly?

Ask your trainer to give you feedback on your performance.


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Activity 11: Replace a blown indicator globe on your trailer

Demonstrate for your trainer or mechanic the removal and

replacement of your trailer indicator globe, a clearance lamp globeand your number plate globe.


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Activity 12: Test the continuity of a low tension lead

Test for a short circuit or a break in a low tension lead with a series

test-light.


1. Prepare the series test-light, connect inputlead to the vehicles battery?

2. Disconnect the input and output leads fromthe part:

use a suitable tool to disconnect the

screw type

pull on the terminal cover to disconnectthe push-on type?

3. Connect the red test-clip to the input terminaland the black test-clip to the body (earth) onthe part being tested?

4. Turn on the test-light switch?

5. Observe the test-light?

(The light will glow when a short circuitexists.)

6. Turn off the test-light switch?

7. Disconnect the test-light clips from the part?

8. Disconnect the test-light input lead from thevehicles battery?

9. Reconnect the input and output leads to thepart and make sure they are secure?

1.0. Check the operation of the circuit?



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Activity 13: Replace a faulty low tension lead on your trailer

Replace a faulty electrical low tension lead. Ask your trainer to

check your work.


1. Select a roll of new LT lead with the sameamp rating or a higher amp rating than theoriginal?

2. Select the same colour wire for identificationpurposes:

select suitable terminals and terminalcovers:

use the same type as those whichwere cut from the old lead?

3. Measure the length of the original lead andcut the same length from the roll?

4. Correctly fit the terminal covers to the lead?

5. Lay the lead along the wiring harness?

6. Release the wiring harness tabs or springclips?

7. Use insulation tape to secure the lead to thewiring harness in several places?

8. Reclamp the wiring harness to the body?

9. Connect both ends of the lead to their

respective parts?

10. Connect the battery and the operation of thecircuit?



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Replace tail light lens

To remove lens from external light:

determine the retaining method; it may be:

two or more screws through the lens

two or more screws through a retainer or a trim

using a suitable screwdriver, remove the screws whileholding the lens

remove the retainer (where applicable)

grip the lens firmly and ease it away from the light body

remove and discard the seal

obtain the replacement lens and seal from stores:

make sure it is a genuine replacement part

install a new seal to the body of the lens

position the lens on the light body

secure the retaining device:

insert and tighten the retaining screws while the lens is heldfirmly against the light body

check that tail lights are working

record and report maintenance and repairs in accordance withcompany procedures.


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Additionalresources


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Paper based:

relevant learners handouts, guidelines and referencematerials, such, as:

The Australian Truck Drivers Manual

Guidelines for the safe carriage of loads on road vehicles, LoadRestraint Guide

state/territory regulation authority material e.g. RTA (NSW)Heavy Vehicle Drivers Handbook. Vic Roads The Victorian

Bus and Truck Drivers Handbook. Other material may be

obtained from various state/territory authorities

relevant government acts and legislation, covering heavy vehicleroad law and operation

relevant manufacturers manuals

a range of trucks specific to training requirements

spare parts required for relevant tasks

a range of hand tools and equipment

cleaning materials

written assessment tasks, where required

real or simulated road transport environment.


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Assessmenttasks


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These assessment tasks relate to the Unit of CompetencyTDT B7 97B Carry out maintenance of trailers

Elements of competency

Identify faults and perform routine maintenance

Carry out repairs on trailers

Complete documentation

Assessment 1: Check trailer suspension

Sub-Tasks StepsDid the learner:

Assessment(Comp, NYC)

Initials ofAssessor

1. Check leaf springsuspension

Check for:

broken or misalignedleaf springs?

broken or misalignedlocating bolts andcentre bolt?

tightness of U-bolt(visually)?

worn or damagedsuspension bushes?

security and conditionof spring hangers?

2. Check air bagsuspension

Check for:

security and conditionof rubber cushion?

security and conditionof drive pin bushing?

visible damage to and

security of loadlevelling devices?

security and conditionof air bag mountings?


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Initials ofAssessor

3. Report faults take corrective action

on those matters whichare considered thedrivers responsibility?

report all other faults tothe appropriatecompany personnel sothat corrective actionmay be taken?

4. Observe OHSprocedures

observe andimplement all

Occupational Healthand Safety practiceswhile conducting thetrailer suspensioncheck?


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Assessment 2: Change a wheel

Sub-Tasks Steps

Did the learner:

Assessment

(Comp, NYC)

Initials of

Assessor1. Park and securethe vehicle

park on a level flathard surface to allowjack to be usedsafely?

switch off the ignition?

switch the hazardwarning light on?

place reflectivetriangles/portable

lamps in appropriatepositions?

place chocks in frontof and behind thewheels, other than thewheel to be jacked?

2. Locate jack andstand

check jack and standare in good condition?

check jack and standhave adequate loadcapacity?

3. Remove spare tyrefrom carrier

remove spare wheelfrom carrier?

place spare wheelbeside the flat tyre?

4. Jack thevehicle/axle toappropriate height

locate jack points?

place base plateunder jack?

place jack and stand

under axle housing,as close to the flattyre as possible?

jack the vehicle untilsaddle engages thejacking point, and thejack takes the weightof the vehicle?


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Initials ofAssessor

loosen wheel nuts

with a wheel brace,without fullyremoving?

jack the vehicle untilthe wheel is free fromroad surface?

place safety stands (ifappropriate), belowthe axle and as closeto the jack aspossible?

5. Release pressurefrom cleats, if fitted

safely releasepressure from wedgeby tapping with wheelbrace?

6. Remove all nuts,studs and cleats (asapplicable)

loosen nuts, studsand cleats with wheelbrace, and remove?

place nuts, studs andcleats onto flat

surface or anappropriate place?

7. Remove outerwheel andspacer/dish rim

place wheel bracehandle under bottomof tyre, and takeweight off tyre?

use a short sharpupward movementwith wheel bracehandle?

remove wheel withtheir back to thewheel, and by placingboth hands under topof rim of wheel?


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Initials ofAssessor

ensure the wheel does

not damage studs (asapplicable), as thewheel is removed?

lean the wheel againstthe vehicle?

remove and placespacer (as applicable)beside the removedwheel?

8. Remove inner

wheel

place wheel brace

handle under bottom oftyre, and take weightoff tyre?

use a short sharpupward movement withwheel brace handle?

pull tyre with otherhand?

slide rim off hub?

9. Replace innerwheel

check spare tyre andclean dirt from its rim?

place the rim intoposition, lined-up withthe spider, hub orretaining studs, andensure the valve facesoutwards?

use wheel bracehandle to lift tyre, thenpush wheel into

position, ensuringvalve is centredbetween two studs?

inspect, clean then refitthe spacer/dish rim (asapplicable)?


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Initials ofAssessor

10. Replace outer

wheel and tightenwheel nuts

ensure that the valves

are placed so accessto both is easy?

replace individualcleats, retaining studsand nuts?

tighten all nuts insequence, (refer todiagrams overleaf)?

rotate the wheel, andcheck run-out on the

rim? confirm run-out is

aligned correctly?

re-tighten all nuts insequence?

11. Lower andremove jack

smoothly lower andremove the jacksafely?

securely tighten allwheel nuts in

sequence?

12. Replaceequipment

place flat tyre intocarrier and re-secure?

replace tools, jack andstand?

remove chocks,warning signs/hazardlights?

13. Observe OHS

practices

observe and

implementoccupational healthand safety practices,during all sub-tasks inthe wheel changingprocess?


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Assessment 3: Replace a faulty globe

Sub-Tasks Steps

Did the learner:

Assessment

(Comp, NYC)

Initials of

Assessor1. Prepare thevehicle

park the vehicle on aflat level surface, ifpossible?

engage Neutral, ifmaxi brakes are fitted,or a gear contrary tothe prevailing slope?

confirm the park brakewas applied and

holding? isolate the circuit in

accordance withcompany policy andvehicle specification?

2. Remove the globe ensure the appropriatecircuit is off?

correctly gain accessto globe depending onwhether rear of light

can be exposed?

correctly identify theblown globe andwithdraw it from theholder?

3. Replace the globe check that thereplacement globe isthe correct type?

ensure that the holdercontacts are clean, or

clean if required?

install the globewithout use of undueforce?

check the globesoperation beforereplacing lens?


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Initials ofAssessor

confirm that the lens

cover was correctlysealed?

4. Observe OHSprocedures

observe andimplementoccupational healthand safety practices,during all sub-taskswhile replacing theglobe?


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Assessment 4: Replace a lens

Sub-Tasks Steps

Did the learner:

Assessment

(Comp, NYC)

Initials of

Assessor1. Prepare thevehicle

park the vehicle on aflat level surface, ifpossible?

engage Neutral, ifmaxi brakes are fitted,or a gear contrary tothe prevailing slope?

confirm the park brakewas applied and

holding? isolate the circuit in

accordance withcompany policy andvehicle specifications?

2. Remove the lens determine the retainingmethod?

use the correct screwdriver?

ease lens away fromlight body withoutleverage?

remove and discardthe seal?

3. Replace lens use an appropriate,company approvedreplacement part?

install a new seal?

correctly position the

lens on the light body? secure the retainer or

trim firmly?

check that seal andlens are installedproperly?

check that light isworking?


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Initials ofAssessor

4. Observe OHS

procedures

observe and

implementoccupational healthand safety practices,during all sub-taskswhile replacing thelens?


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Feedback onactivities

The responses provided in this section are suggested responses.Because every workplace is different, your responses may varyaccording to your specific workplace procedures, the equipmentavailable and the nature of the business.


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Activity 3: Demonstrate to your trainer axle fault diagnosis

Faults and their probable causes

Fault Cause

Hub running hot Bearings incorrectly adjusted.

Under or over greasing, orunsuitable grease.

Premature bearing failure Bearings installed wrongly (tootight or too free).

Insufficient or unsuitable grease.

Dirt or foreign bodies in hub.

Wrong offset wheels fitted.

Excessive shock loading (kerbmounting or hitting pot holes atspeed).

Overloading.

Damaged wheel studs/bolts Insufficient care taken in the fittingof wheel studs or bolts.

Wheel stud locknut inside drumnot properly tightened and locked,consequently stud will eventuallywork loose in service.

Wheel nut not tightened torecommended torque.

Broken axle beam. Overloads.

Inferior welding.

Welding across high stress zones.

Spring seat centres belowrecommended minimum


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Fault Cause

Excessive tyre wear Incorrect tyre pressures.

Loose U Bolt nuts.

Axle out of alignment.

Tyres unmatched.

Spring seats off axle top deadcentre (toe-in or tow-out).

Bent axle.

play in bearings (excessive end-float).

Brakes binding Faulty return spring.

Delay in brake release valve orbrake chamber.

Inefficient brakes Worn linings

Air pressure loss.

Slack adjuster needs taking up.

Slack adjuster collar stop pinsheared or loose.

Failed hub seal permits grease toleak onto brake linings.

Worn cam shafts.


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Training recordinformation

forTDT B7 97B Carry out maintenance of trailers


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Personal details

Name ...........................................................................................................

Telephone number .......................................................................................

RTO details

Name of RTO ..............................................................................................

Name of RTO trainer/assessor ....................................................................


Employer details

Name ...........................................................................................................

Address .......................................................................................................

......................................................................................................................


Workplace supervisor/trainers name .........................................................

Workplace supervisor/trainers work telephone number .............................

Complete this section if you have two different employers oryou change employers.

Name ...........................................................................................................

Address .......................................................................................................

......................................................................................................................


Workplace supervisor/trainers name .........................................................

Workplace supervisor/trainers work telephone number ............................


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Introduction

This training record information is part of the Learners Guide for this unit

of the Transport and Distribution Training Package.

The training record information:

is a permanent record of the knowledge and skills you havegained at work and during your training

shows your trainer what training you have completed

records details of your assessment against this unit.

It is the only record of the training and assessment you have

completed and it is essential that you keep it safe and clean.


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How to use the assessment checklist andrecord sheets

It is your responsibility to make sure that you:

keep the assessment checklist and record sheets in a safeplace

arrange for your workplace assessor to sign and date eachsheet after you have been assessed successfully. Make sure

your record sheets are always up to date. (Your assessor

might be the same person as your trainer but not necessarily).

Why is it important that your assessment isrecorded?

You may be assessed by different people and in different ways. The

assessment checklist and record sheets are used to make sure that all your

successful assessments are recorded. They should be stored in one place.

You will need a record of all your completed training and assessments if

you would like to work towards completing a certificate.

The assessment checklist and record sheets can also be used to recordassessments of the skills you have gained from other jobs or training. This

is called Recognition of Prior Learning (RPL) or Recognition of Current

Competence (RCC) and means you can be assessed without doing the

training but still make sure your skills are recognised. Speak to your

assessor, workplace trainer or supervisor if you think you would like an

RPL/RCC assessment.


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How will you be assessed?

You could be assessed in many different ways. An assessor may:

watch you perform your normal work duties

set you specific tasks to do

talk to you about how you normally perform your duties

ask you specific questions

ask you to assess your own strengths and weaknesses at work

talk to people who are willing to speak on your behalf

organise a formal test for a licence or certificate ofcompetence.

Assessors can also decide to:

observe your performance more than once

ask you to do some additional tasks

ask you to show your skills in a slightly different way.

If you are not successful the first time you are assessed, you can:

try again at another time

ask your assessor, supervisor or trainer for more guidance do some more practice.

When you are successful, your assessor will record the assessment on

your training record sheet by dating and signing it. You should also sign it

at the same time.

What is the assessors role?

The assessor must:

organise a place and time for the assessment with you, yoursupervisor and your trainer

give you feedback on your progress

record the results of your assessments regularly

date and sign your assessment checklist and record sheets.


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Assessment checklist and recordsheets

The next section contains the assessment checklist and record sheets for

this unit. Your assessor will use this section to record the completed

assessment for the unit.

Remember to take this sheet with you when you are being assessed .


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Assessment checklist and recordsheet

This assessment checklist and record sheet is for an assessmentagainst a single unit. If assessment is against a group ofcompetencies, an appropriate Assessment Kit will be used. Theseare designed for assessment in occupational areas against a groupof related competencies.

Space is provided for additional or alternative assessment activitiesto be recorded.


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Learners details

Learners name

Workplace

Learners occupation/job

Relevant licenses (if required) sighted? YES NO

Assessment details

Assessors name and RTO details

Agreed date(s) for assessment

Assessor qualifications

Summary of assessment tasks

1. Check trailer suspension

2. Change a wheel

3. Replace a faulty globe

4. Replace a lens

Assessment result

Competent? Not yet competent?

Comment if NYC

Has the appeals process been explained to learner? YES NO

Has an appeal been requested? YES NO


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Assessment details

NOTE: indicates satisfactory performance or responseX indicates unsatisfactory or insufficient response or performance

DEMONSTRATIONS (Attach checklists used in assessments)

Summary of requiredperformance

X Comments/observations byassessor

QUESTIONING (Insert questions asked and summarise responses given)

Questions Responses X


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DOCUMENTS (Attach any documents produced for the assessment)

Document Comments X

OTHER EVIDENCE

Add details of any further evidence sought from learner such as samples,reports from supervisor or manager, workplace projects etc and comments onsuitability of evidence.

Details of evidence Comments X

Signatures

As the learner I have been informed of the assessment result and the reasonsfor the decision. I have been advised of appropriate follow up activity and theappeals process.

TLIB707C - Carry Out Maintenance of Trailers - Learner Guide

Documents