US Praxis PRX90 User manual

USPraxis,Inc.–Copyright2009©Allrightsreserved 1
PRX90&PRX130
OPERATIONS&OWNERSMANUAL
USPraxis,Inc.
955W.PrairieDriveSycamore,IL60178
TollFree:(888)3168200
Ph:(815)8999700
Fax:(815)8999709
Web:www.uspraxis.com

USPraxis,Inc.–Copyright2009©Allrightsreserved 2
TABLEOFCONTENTS
PraxisStumpMachinesPRX90&PRX130
Introduction………………………………3
Use&Service………..………………….3
SafetyInstructions……………………….4
GeneralUse………………...……………4
Preparingto
Use………..….…………….6
ProtectiveEquipment…..….………..…...8
Operating……..………..….……………..9
Movement/Transport.…..….………...…10
Storage…..…………….….……………10
FuelSystem………..…………………...11
Maintenance………...……………..…...12
Controls………………………………….13
Engine…………………….……………13
Throttle…..……………………………13
Starter……….……........………………13
StarterHandle…….……………………14
FuelValve.….…….……………………14
ChokeControl…….……………………14
AirFilter….……….……………………14
SparkPlug.……….…………….………15
Muffler…..……….…………….………15
OilDipstick……………………….……15
OilDrainage……….………….…......…16
FuelTank………….………….…......…16
Fueling…………….………….…......…16
CentrifugalClutch…………….…......…17
Throttle…………….………….…......…17
Brake…………..….……….….…......…17
OperatingThemachine….……..………18
BeforeyouStart…………...………..…18
StartingtheEngine…..….….………….19
FuelValve…………...……………...…19
ChokeControl………..….….………….19
ThrottleGripHandle...………….…...…19
StarterHandle………..……………...…20
GrindingtheStump…..……………...…21
NormalShutdown…..…………..…...…22
Maintenance……………………….……24
MaintenanceSchedule…………………24
CleaningtheFilter…..…………………25
ReplacingtheFilter……………………26
CleaningtheSludgeReservoir……..…27
IdleAdjustment….……………………27
IgnitionSystem.….……………………28
CuttingBlade…….……………………29
SharpeningCuttingBlades……………30
BrakeAdjustment….…………………31
TwoMinuteRule…..…………………31
Cleaning&Washing.…………………31
LubricatingBearings.…………………31
DriveBelt…………..…………………32
TroubleShooting………………….……33
Storage&TechnicalData.……….……36
WinterStorage…….…………………36
Service…………….…………………36
Specifications.…….…………………37
ServiceJournal………………………38
PartsList………………...……….……40
HandleAssembly……………………40
Chassis&FlapAssembly……………42
Chassis&EngineAssembly…………44
Brake&WheelAssembly……..……46
Brake&ShaftAssembly……………48
Belt,Guard&DriveAssembly…..…50

USPraxis,Inc.–Copyright2009©Allrightsreserved 3
INTRODUCTION
Congratulations:
ThankyouforpurchasingaPraxisstumpgrinder.Throughyourconfidenceinus,youhavechosenan
exceptionally highqualityproduct.
Thismanualisavaluabledocument.ItdescribesyournewPraxismachine.Readthemanualcarefully
before attemptingtousethemachine.Followingtheinstructions(use,service,maintenance,etc.)can
considerablyincreasethelifespanofyourmachineandevenincreaseitsresalevalue.Pleasecontactyour
dealerformoreinformation.
IfyousellyourPraxismachine,makesuretogivetheoperator’smanualtothenewowner.
Use:
The Stump Machine isusedtoremovetreestumps.Bymovingthebladeinsweepingmovementslaterally
overthetopandfrontofthestump,youcangraduallygrinditaway.Readthechapter“Safetyinstructions”
beforeyouusethemachineforthefirsttime.
Insureyourmachine:
Contactyourinsurancecompanytocheckoninsurancecoverageforyournewmachine.Youshouldhaveall
inclusiveinsuranceforliability,fire,damageandtheft.
Goodservice:
Praxisproductsaresoldallovertheworldandonlyinspecializedretailtradewithcompleteservice.This
ensuresthatyouasacustomerreceiveonlythebestsupportandservice... Beforethemachinewasdeliveredit
underwent inspectionandwasadjustedbyyourdealer.Whenyouneedsparepartsorsupportinservice
questions,guaranteeissues,etc.,pleaseconsultthefollowingprofessional:
TheOperator’sManualbelongstomachinewith
serialnumber:
Enginenumber:
Serialnumber:
Theserialnumbercanbefoundontheprintedplateattachedtotheframe,nexttotheengine.Theplate
includesthefollowinginformation:
Themachinestypedesignation(MODEL).
Themachinesserialnumber(S/N).
Pleasestatethetypedesignationandserialnumberwhenorderingspareparts.
Theenginesserialnumberispunchedinthecrankcaseundertheoillevelguard.
Theenginetypeisspecifiedonthecrankcasetotherightoftheoillevelguardbutalsoappearson
thedecalon thestarter.
Pleasestatethesewhenorderingspareengineparts.

USPraxis,Inc.–Copyright2009©Allrightsreserved 4
SAFETYINSTRUCTIONS
Generaluse:
TheobjectofthismanualistohelpyouuseyourPraxismachinesafelyandtogiveyou
informationabouthowtomaintainyourmachine.Pleasereadthemanualcarefullybefore
attemptingtousethemachine.
Readthismanualcarefullyandmakesureyouunderstanditbeforeusingthemachineor
performinganymaintenance.Itistheresponsibilityofthemachineownertoexplainthecontents
totheuser.
Ifafterreadingtheoperator’smanualyouarestillunsureaboutthesafetyrisksassociatedwith
useofthemachine,youshouldnotusethemachine.Pleasecontactyourdealerormanufacturer
formoreinformation.
Thesesafetyinstructionsonlyaddressthebasicsforsafeuse.Itwouldbeimpossibleinthesafety
instructionstodescribeallpossiblerisksituationsthatcouldarisewhenusingthemachine.You
canhowever,preventaccidentsbyalwaysusingcommonsense.
Toobtainextracopiesoftheoperator’smanual; pleasecontactyourdealerorthemanufacturer.
IMPORTANTINFORMATION
Donotusethemachineuntilyouhavereadtheoperator’smanualcarefullyand
understandtheinstructionsgiven.Allmaintenanceworkoradjustmentsnotdescribedin
thismanualmustbeperformedbyanauthorizedPraxisserviceprovider.
Thestumpgrindercanbedangerousifusedimproperlyorwithoutduecareandcanlead
toseriousaccidents,intheworstcasesevenfatalaccidents.Itisveryimportantthatyou
readthisoperator’smanualandunderstandtheinstructionsbeforeyouattempttousethe
machine.
Undernocircumstancesmaytheoriginaldesignofthemachinebemodifiedwithout
writtenapprovalfromthemanufacturer.Suchmodificationsnotonlyaffectthe
performanceanddurabilityofthemachine,butmayevenposeasafetyriskforusersand
thoseinthevicinity.Unauthorizedmodificationstothedesignofthemachinemayabsolve
themanufacturerfromliabilityforanyresultingpersonalinjuryorpropertydamage.
Modifyingthemachinewithoutwrittenapprovalfromthemanufacturermayvoidthe
guarantee.

USPraxis,Inc.–Copyright2009©Allrightsreserved 5
SAFETYINSTRUCTIONS
Continued
Ø Followallsafetyinstructions.Failurecouldresultin seriousinjurytoyourselforothers.
Ø Accidentpreventionregulations,othergeneralsafetyregulations,occupationalsafetyrules
andtrafficregulationsmustbefollowedwithoutfail.
Ø Allusersmustbetrainedinuseof themachinebeforetheybeginoperatingit.Theowner
isresponsiblefortrainingusers.
Ø EngageanauthorizedPraxisserviceproviderforallserviceandrepairsnotdescribedin
thismanual.
Ø Praxisoriginalsparepartsaredesignedandspecifiedtomaintainhighqualityandcorrect
fitforoptimaldurabilityandlifespan.Fromasafetypointofview,youshouldonlyuse
Praxisreplacementparts.
Ø Learnhowtousethemachineanditscontrolssafelyandlearntorecognizethesafety
decalsandtheirmeaning.
Ø Onlyusethemachineforremovingtreestumpsandexposedrootsystems.Itisnot
intendedforanyotheruse.
Ø Checkthatthemachineisinserviceableconditionpriortouse;seethechapter
“MaintenanceandTroubleShooting”.
Ø Onlyusethemachineindaylightorinotherwell litconditions.Keepthemachineasafe
distancefromholesorotherirregularitiesintheground.Payattentiontootherpossible
risks.
Ø Onlyallowthemachinetobeusedbyadultswhobyadultswhoarefamiliarwith itsuse.
Ø Neverallowchildrenorpersonsnotrainedintheuseofthemachinetouseorserviceit.
Locallawsmayregulatetheageoftheuser.
Ø Peopleandanimalscandistractyoucausingyoutolosecontrolofthemachine.Forthis
reason,youshouldalwaysconcentrateandfocusonthetaskathand.
Ø Neverleavethemachineunsupervisedwiththeenginerunning.
Ø Makesurethatotherpeoplearenearbywhenyouareusingthemachinesothatyoucan
callforhelpshouldanemergencyarise.
Ø Themachineistestedandapprovedonlywiththeequipmentoriginallyprovidedor
recommendedbythemanufacturer.

USPraxis,Inc.–Copyright2009©Allrightsreserved 6
SAFETYINSTRUCTIONS
Continued
Theenginecanbecomeveryhot.Toavoidbeingburned,youmustturnofftheengineand
waituntilallpartshavecooledbeforetouchingtheengine.
Overexposuretovibrationmayleadtocirculatoryornervedamage,particularlyinpeople
whohaveimpairedcirculation.Contactyourdoctorifyouexperiencesymptomsthatcould
havebeencausedbyoverexposuretovibration.Examplesofcommonsymptomsinclude
numbness,pain,muscleweakness,changeofskincolororanuncomfortablefeelingof
tingling.Thesesymptomsappearmostfrequentlyinthefingers,handsorwrists.
IMPORTANTINFORMATION
Neveruseastumpgrinderthatisdamagedorincorrectlyadjusted.Neverusethestump
grinderifanycomponentismissingorifitisnotproperlyassembled.Checkthatthe
cuttingtoolsstoprotatingwhenyoureducethethrottle.Ifyoufindyourselfinasituation
whereyouarenotsurewhattodo,alwaysseekexpertassistance.DONOTtrytoattack
anyproblemyouarenotqualifiedtoresolve.

USPraxis,Inc.–Copyright2009©Allrightsreserved 7
SAFETYINSTRUCTIONS
Continued
Preparations:
Ø Makesurethatyoualwayshavefirstaidequipmentathandwhenusingthemachine.
Ø Makesurenobodyelseisinthevicinityofthemachinewhenyoustarttheengine,
engagethedriveorrunthemachine.
Ø Makesureanimalsandpeoplemaintainasafedistancefromthemachine.
Ø Cleartheareaofobjectssuchasstones,toys,steelwire,etc.thatcouldbecomecaughtin
movingmachinepartsandthrown out.
Ø Findandlocateallfixedobjectsintheground,suchassprinklersystems,poles,water
valves,basesforwashinglines,etc.Becertaintocheckforhiddenelectrical cablesor
similarinthesurfaceofthelawn.Alwaysrunthemachinearoundtheseobjects.Never
intentionallyrunthemachineoverforeignobjects.
Ø Checkthedeadman’sgripandallguardsarefittedandfunctioning. DONOTusethe
machineifitisnotworkingproperly.
Ø Makesurenoclothing,longhairorjewelrycancatchinmovingmachineparts.
Ø Checkthatallsafetydecalsareinplace.Seethechapter“Locationofdecals”.
Ø Usemouthprotection,protectivegloveswithgoodgripandprotectiveclothingwhichyou
canmoveunrestricted.Alsouselegprotectiontoprotectyourlegsfrom sparksandthe
cuttingtools.
Ø Neverusethemachinewhenbarefoot.Alwayswearprotectiveshoesorprotectiveboots
withantislipandpreferablywithsteeltoes.
Ø Useahelmetwithafullfacevisororameshvisorandprotectiveglasses.Wearapproved
earprotectionwhenrunningthemachine.Asktourdealeraboutapprovedprotective
glasses,earprotectionandrecommendedhelmets.
Alwaysuseapprovedprotectiveclothingandapprovedprotectiveequipmentwhenusing
themachine.Protectiveclothingandprotectiveequipmentcannoteliminatetheriskof
accidents,butwearingproperclothingandthecorrectequipmentwillreducethedegreeof
injuryshouldanaccidentoccur.Askyourdealeraboutapprovedprotectiveclothingand
approvedprotectiveequipmentrecommendedbyPraxis.

USPraxis,Inc.–Copyright2009©Allrightsreserved 8
SAFETYINSTRUCTIONS
Continued
Protectiveequipment:
Consultyourdealerwhenselectingprotectiveequipment.Ourdealershaveabroadassortmentof
equipmentforprofessionalssuchasforestryworkersandknowledgeaboutoccupational
environmentrequirementsandprotectivelevels.
Beforeusingthestumpgrinder,youmayinmanycasesneedtocutbacktoobjectwithapower
saw.Hence,itisappropriatetousepersonalprotectiveequipmentthatfulfilsrequirementsfor
workingwithbothstumpgrindersandpowersaws.
Themaindifferenceisthatyoushouldwearprotectiveglasseswhenoperatingthestumpgrinder
whilethewiremeshvisorgivessufficientprotection whenusingapowersaw.Thuswhenusing
thestumpgrinder,werecommendusingbothawiremeshorvisortoprotectyourfaceand
protectiveglasses.Alternatively,youcanuseaPlexiglasfaceguard,butitscratchesmoreeasily
andismoresusceptibletosoilingandfogging.

USPraxis,Inc.–Copyright2009©Allrightsreserved 9
SAFETYINSTRUCTIONS
Continued
Operating:
Ø DONOTusethemachineongradesof morethan10
degrees.
Ø DONOTusethemachineifyouaretired,ifyouhave
consumedalcohol,orifyouaretakingotherdrugsor
medicationthatcanaffectyourvision,judgmentor
coordination.
Ø Neverusethemachineindoorsorinspaceslacking
properventilation.
Ø Makesureyouhaveaproperfootholdwhen usingthemachine,particularlywhen backing.
Walk,don’trun.Neverworkon wetgrass.Poortractionmaycauseyoutoslip.
Ø Keepyourhandsandfeetawayfrommovingparts.
Ø Keepyourhandsandfeetawayfromtheworktools.
Ø DONOTuseyourfeetorotherpartsofyourbodypartsofyourbodytogaingreater
bearingpressureagainstthestump.
Ø Smoking,openflamesorsparksinthevicinityofthemachinearestrictly
forbidden.Gasolineisextremely flammableandcarelessnessinhandlingcanresultin
personalinjury orfire.
Ø Neveruseamachinewithadeflectivemuffler.
Ø Inverywarmanddryclimates,stumpgrinder
operationposesariskofforestfires.
Ø Stopandinspecttheequipmentifyourun overorinto
anything.Ifnecessary,makerepairsbeforebeginning
again.
Ø Whateverhappens,youshouldalwaysparkthe
machineonevenground,disengagethe drive,activate
theparking,turnofftheengineandwaituntilallmovingpartshavestoppedbeforeleaving
theoperatingposition behindthemachine.
Ø Seriousaccidentscanoccurifyoufailtobeonguardforchildreninthevicinityofthe
machine.Neverassumethatchildrenwillstayputwhereyoulastsawthem.

USPraxis,Inc.–Copyright2009©Allrightsreserved 10
SAFETYINSTRUCTIONS
Continued
Ø Keepchildrenawayfromthemachine.
Ø Keepchildrenawayfromtheworkareaandunderclose
supervisionbyanotheradult.
Ø Neverallowchildrentooperatethemachine.
Ø Beparticularlycarefulnearcorners,bushestreesorother
objectsthatblockyourview.
Movement/Transport:
Ø Toturnandsteerthemachine,pressdownonthehandleandturnonthebackwheels.
Ø Turnofftheengineandallowittocoolatleast2minutesbeforetransport.
Ø Becarefulandusesafeliftingandmovingtechniqueswhenloading/unloadingthe
machine.
Ø Werecommendhavingtwopeopletoliftthemachine.
Ø Activatetheparkingbrakeduringtransport.
Ø Fastenthemachineproperlyinplacewithapprovedfasteners,suchastensionbelts,
chainsorrope.Alwayscheckthatyouareincompliancewithapplicabletraffic
regulationsbeforetransportingthemachine.
Storage:
Ø Allowtheenginetocoolbeforestoringthemachine.Neverstorethemachinenearan
openflame.
Ø Storethemachinewiththefuelvalveclosed.
Ø Storethemachineandfuelinsuchawaythatthereisnoriskthatleakingfuelorfumes
cancomeincontactwithflamesorsparksfromelectricalmachines,electricengines,
relays,switches,boilersorsimilar.
Ø Storethemachineinalockedspaceaway fromchildrenandadultsuntrainedinuseof
themachine.

USPraxis,Inc.–Copyright2009©Allrightsreserved 11
Ø Neverstoreoroperatethemachinenearanopenflame.
SAFETYINSTRUCTIONS
Continued
FuelSystem:
Ø Onlystorefuelincontainersapprovedforthatpurpose.
Ø Neverremovethefuelcapandfillthefueltankwhentheengineisrunning.
Ø Alwaysstoptheenginewhenrefueling.
Ø Donotsmokewhenfillingthegasolinetankanddonotpourgasolineinthevicinityof
sparksoropenflame.
Ø Neverfillthefueltankindoors.
Ø Beforestartingthemachineafterrefueling,itshouldbemovedatleast10feet(3M)
fromthelocationwhereitwasfilled.
Ø Turnoffthefuelsupplyforstorageortransport.
Ø Ifleaksariseinthefuelsystem,theenginemustnot
bestarteduntiltheproblemhasbeenresolved.
Ø Checkthefuellevelbeforeeachuseandleavespace
forthefueltoexpand,becausetheheatfromthe
engineandthesuncan otherwisecausethefuelto
expandandoverflow.
Ø Avoidoverfilling.Ifyouspillgasolineonthe
machine,wipeupthespillandwaituntil ithas
evaporatedbeforestartingtheengine. Ifyouspill
gasolineonyourclothing,changeyourclothing.
Ø Closethefuelvalve.
Gasolineandgasolinefumesarepoisonousandextremelyflammable.Beespecially
carefulwhenhandlinggasoline,ascarelessnesscanresultinpersonalinjuryorfire.

USPraxis,Inc.–Copyright2009©Allrightsreserved 12
SAFETYINSTRUCTIONS
Continued
Maintenance:
Ø Nevermakeadjustmentswiththeenginerunning.
Ø Disengagethedriveunits,shutofftheengineand
waituntilallmovingpartscometoacomplete
stopbeforemakingadjustments,performing
maintenanceorcleaningthemachine.
Ø Disconnectthesparkplugcablebeforebeginning
repairwork.
Ø Keepallcomponentsinserviceableconditionand
makesureallnuts,bolts,etc.aretight.
Replacewornordamageddecals.
Ø Becarefulwhencheckingworktools.Usegloveswhenperformingmaintenancework.
Ø Neverallowpersonsnottrainedintheuseofthemachinetoperformserviceonit.
Ø Alwaysparkthemachineonevengroundbeforeperformingmaintenanceormaking
adjustments.
Ø Donotdisassembletheengine.Thiscan invalidateyourenginewarranty.Contactyour
dealerifyouhaveanyquestionsregardingserviceorguaranteematters. Followall
maintenanceinstructions.
Ø Donotchangethesettingofgovernorsandavoidrunningtheenginewithoverlyhigh
RPM. Ifyouruntheenginetoofast,youriskdamagingthemachinecomponents.
Ø Donotmodifysafetyequipment.Checkregularlytobesureitworksproperly.The
machinemustnotberunwithdefectiveofdisassembledsafetyequipment.
Ø Themufflerisdesignedtomaintainsoundlevelsatanapprovedlevelandkeepdirect
exhaustawayfromtheuser.Exhaustgasesfromtheengineareextremelyhotandmay
containsparksthatcancausefiresorburntheuser.
Ø Neveruseamachinewithadefectivemuffler.
Ø Reducetheriskoffirebyremovinggrass,leavesandotherdebristhatmayhavecaught
inthemachine.
Waituntilallmovingpartsarecompletelystillbeforeperformingmaintenanceonthemachine.
Turnofftheengineandremovethesparkplugcable.
Disconnectthesparkplugcable.

USPraxis,Inc.–Copyright2009©Allrightsreserved 13
CONTROLS
Engine:
Exteriorenginecomponentsandcontrols.
1.Throttle
2.Starter
3.Starterhandle
4.Fuelvalve
5.Chokecontrol
6.Airfilter
7.SparkPlug
8.Muffler
9.Oildipstick
10.Oildrainage
11.Oillevelguard
13.Fueltank
14.Fuelfillercap
Throttle:
Theleverontheengineisnormallynotused.Itis
connectedtothethrottleonthehandle.Ifthecable
shouldbindorbreak,youcanreducethethrottlewith
theleverontheengineasanemergencymeasureto
slowtheenginespeedtoanidleandstopthecutting
wheel.
Starter:
Thestarterisofthemagnapulltypewithspringreturn.
Toreplacethereturnspringorstartercord,contact
anauthorizedserviceworkshop.

USPraxis,Inc.–Copyright2009©Allrightsreserved 14
CONTROLS
Continued
Starterhandle:
Misuseofthestarterhandlecandamagethestarter.Donottwistthestartercordaroundyour
hand.
Pulloutthehandleslowlyuntilthegearsmesh.Do
notpulloutthestartercordcompletelyanddonotlet
goofthestarterhandlewhenextended.
Fuelvalve:
Thefuelvalveopensandclosestheconnection
betweenthetankandthecarburetor.
Theillustrationshowsthetankvalveclosed;toopen,
turnthelevercompletelytotheright.Thereisno
middleposition.
Turnoffthevalvewhenthemachineisnotinuseto
avoidfloodingthecarburetor.
Thefuelvalveiscombinedwithasludgereservoir.
Chokecontrol:
Thechokecontrolopensandclosesthechokevalvein
thecarburetor.Thisisonlyusedtostartacold
engine.
Theimageshowsthechokevalveopen;toclose,
movethelevertotheleft.Themidwaypositionscan
beused.Whentheenginestarts,thelevercanbe
movedgraduallytotherightaslongasitcontinuesto
runsmoothly.Forgettingthechokeisevidentasthe
enginerunsroughlyandproducesblacksmoke.
Thisalsoresultsinincreasedfuelconsumption.
Airfilter:
Theengineairfilterconsistsofacyclonefilterandafinefilter.
Airisdrawninthroughthescreen(3)onthecyclonefilterandcoarserpollutantscollectinthe
container(4).

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Airfilter(Continued):
Thefinefilter,whichconsistsofacyclonefilterandafinefilter.
Airisdrawninthroughthescreen(3)onthecyclonefilterandcoarserpollutantscollectinthe
container(4).
Thefinefilter,whichconsistsofafoamrubberprefilterandapaperfiltercartridge,islocated
underthecowling(2).Thecowlingandthecyclonefiltercanberemovedbyremovingthewing
nut(1).
Seethechapter“Maintenance/CleaningthecyclonefilterandReplacingtheairfilter”forcleaning
instructions.
Runningthemachinewithadirtyairfilterwillcausetheenginetorunonpartialchokeandshow
thesamesymptomsasaforgottenchokedescribedabove.Itcanalsobedifficulttostart.
SparkPlug:
Theenginesparkplugishiddenundertheignitioncable
shoe.Whenperformingservice,itisimportantthatthe
enginecannotstartaccidentally.Forthisreason,always
removetheignitioncableshoefromthesparkplug.To
avoidpullingthecable,thecableshoeisequippedwitha
specialhandle;seetheillustration.
Typeofsparkplug,see“Technicaldata”.
Serviceinstructionssee“Maintenance/Electricalsystem”.
Muffler:
Theenginemufflerisequippedwithaheatprotectivecowling.Nonetheless,itstillbecomeshot
whentheengineisrunning.Avoidtouchingthemufflerwhenitiswarm.Riskforburns.
Oildipstick:
Thedipstickforthecrankcaseoilreservoiris
locatedonthefrontoftheengine.Refilltheengineoilin
theholewherethedipstickfits.
Whencheckingtheoillevel,thedipstickshouldnotbe
screwedin.Themachineshouldbeparkedoneven
groundwiththeenginestopped.Neverruntheengine
withoutthedipstickinplace.Theenginehasanelectronic
oillevelguard.Itstopsandcannotbestartedifthelevel
becomestoolow.Yetyoushouldnotrely
entirelyonthelevelguard;ratheryoushouldchecktheoilusingthedipstick.
Fornormaluse,werecommendSAE10W30weight
engineoilserviceSFSG;seealsothechapter“Lubrication/Engineoil”.

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Oildrainage:
Thedrainagescrew(5)forthecrankcaseoilreservoiris
locatedonthebackoftheengine.
IMPORTANTINFORMATION
Usedengineoilisahealthhazardandlegislation
prohibitsdisposalonthegroundorinnature;it
shouldalwaysbedisposedofataworkshopor
appropriatedisposallocation.Avoidskincontact;
washwithsoapandwaterincaseofspills.
Fueltank:
Underneaththetank,thereisafuelfiltercombinedwithafuelvalve.Thetankvolumeis1.72
Gal.(6.5liters)
Fueling:
Readthesafetyinstructionsbeforefueling.
Keepthefuelandfueltankclean.Avoid
fillingthemachinewithdirtyfuel.Makesure
thefuelcapisproperlytightenedandthe
gasketisnotdamaged,particularlybefore
washingthemachine.
Useunleadedgasolinewithminimum86
octanerating.Neverusegasolinemixedwith
twocycleoil.Forethanolandmethanolfuel,
thefollowingapplies:
Maximumallowableethanol10%(volume).
Maximumallowablemethanol5%(volume).
MaximumallowableMTBE(MethylTertiaryButylEther)15%(volume).
Iftheengine“bolts”atnormalloaditcanbedamaged.Changethefuel.Ifthisdoesnothelp,
contactanauthorizedserviceworkshop.
Donotfillthetankcompletely;leavespaceforthefueltoexpandasitwarmsup.
GasolineIshighlyflammable.Observecautionandfillthetankoutdoors.(Seethesafety
instructions.

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Centrifugalclutch:
Theengineisequippedwithacentrifugalclutchthat
isconnectedtothecrankshaft.Whentheengine
speedincreases,thedriveforcuttingwheelengages
automatically.Thecentrifugalclutchis
maintenancefree;itisnotpossiblefortheuserto
makeadjustments.
Throttle:
Thelevercontrolsenginespeed.
Withtheleverdown,theenginerunsatidleandfunctionsasstartposition.
Whentheenginespeedincreases,thecentrifugalclutchdriveautomaticallyengagesthecutting
wheel.
Brake:
Theleveractivatesadiskbrakeontheleftwheelwhenitispulledbackwards.Thebrakeshould
alwaysbeactivatedwhenoperatingthegrinder,whenitisparkedandwhenitisbeing
transported.
NEVERoperateamachinewithadefectivebrake.

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OPERATINGTHEMACHINE
Beforeyoustart:
Digawaytheearthandremoveanystonesnearthe
treestumpthatmayinterferewithyourwork.
Checkthatthegroundisfreeofforeignobjects,
suchaselectricalcables,barbedwire,etc.
Cutortrimthestumpasnecessaryusingapower
saw.
Reviewallthemachine’ssafetydecals.
Useahardhat,earandeyeprotection.A
meshvisoralonedoesnotprovide
sufficienteyeprotection;supplementwith
protectiveglasses.
Makesurethatyouarefamiliarwithsafety
regulationsandshutdownprocedures
describedpreviouslyintheoperator’s
manual.
Makesurethatallguardsareinplaceand
ingoodcondition.
Makesurethatthebladesandcuttersarein
placeandingoodcondition.
Makesurethattheworkareaandcutterin
particularandfreefrommetallicobjects
suchaswire,nails,etc.thatcouldbe
thrownoutandinjurepersonsinthe
vicinityanddamagetheequipment.
Makesurethateveryone,including
childrenandanimals,maintainadistanceofat
least50feet(15m)fromthemachine.
Debriscanbethrownoutandinjurepeople
andanimals.

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Continued
Startingtheengine:
Checkthatalldailymaintenanceasdescribedinthemaintenanceschedulehasbeenperformed.
Checkthatthereissufficientfuelinthetank.
Fuelvalve:
Openthefuelvalve.Placetheleverall
thewaytotheright.
Chokecontrol:
Whenstartingtheenginewarm,thelever
shouldbeintherightposition;seethe
illustration.
Whenstartingtheenginecoldor
partiallywarm,placethelever
completelyorpartlytotheleft.
Movetheleverbacktotherightonce
theenginestarts.Whentheengineis
cold,itmaybebesttomovethelever
backinseveralstages.Findtheposition
wheretheenginerunssmoothly.
Throttle
SetthethrottleonthehandletotheSLOW(START)/DISENGAGEposition.

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Safetypresencegripbar
Holdinthesafetypresencegripbaragainstthe
handle.
Starterhandle:
Thedeadman’sgripmustbepressedinwhenstarting
theengine.
Misuseofthestarterhandlecandamagethestarter.
DONOTtwistthestartercordaroundyourhand,
Pulloutthehandleslowlyuntilthegearsmesh.Then
giveasharppullonthestarterhandle.
DONOTpulloutthestartercordcompletelyand
DONOTletgoofthestarterhandlewhenextended.
Throttle
Keepthethrottleatidle.Whenthethrottleis
increased,thecuttingwheelwillbeginrotating.