Safety • Assembly • Operation • Tips & Techniques • Maintenance • Troubleshooting • Parts Lists • Warranty
A O A AL
21" Rotary Mower- Model Series 420
iMPORTANT
READ SAFETY RULES AND iNSTRUCTiONS CAREFULLY BEFORE OPERATION
Warning: Thisunitisequippedwithaninternalcombustionengineandshouldnotbeusedon or nearanyunimprovedforest-covered,brush-
coveredor grass-coveredlandunlesstheengine'sexhaustsystemisequippedwitha sparkarrestermeetingapplicablelocalor statelaws(if any).
If a sparkarresterisused,it shouldbemaintainedineffectiveworkingorderby theoperator.IntheStateofCaliforniatheaboveisrequiredbylaw
(Section4442oftheCaliforniaPublicResourcesCode).Otherstatesmayhavesimilarlaws.Federallawsapplyonfederallands.A sparkarrester
forthemufflerisavailablethroughyournearestengineauthorizedservicedealeror contactthe servicedepartment,RO.Box361131Cleveland,
Ohio44136-0019.
FORMNO.769-01609A
PRINTEDIN U.S.A.
MTD LLC, P.O. BOX 361131 CLEVELAND, OHIO 44136-0019
4/2005
This Operator's Manual is an important part of your new lawn mower, it will help you assemble,
prepare and maintain the unit for best performance. Please read and understand what it says.
Table of Contents
Slope Gauge ....................................................... 3
Safe Operation Practices ................................... 4
Setup and Adjustment ....................................... 6
Operating Your Lawn Mower .............................. 8
Finding and Recording Model Number
BEFOREYOUSTARTASSEMBLING
YOURNEW EQUIPMENT,
please locatethe modelplate onthe equipmentand copythe
informationtothe sample modelplate providedtothe right.
Youcan locatethe model plate by standing at the operating
position and lookingdown atthe rear of the deck. This
informationwill be necessaryto usethe manufacturer'sweb
site and/or obtain assistancefrom theCustomerSupport
Departmentor an authorizedservice dealer.
Maintaining Your Lawn Mower ......................... 10
Trouble Shooting .............................................. 12
Safety Labels .................................................... 13
Parts List ........................................................... 14
Model Number
YaRD-MaN)//"
www.yardman.com 330-220-4683
Serial Number
P. O. BOX ;361131
CLEVELAND,OH44136
800-800-731 0
Customer Support
Please do IVOTreturn the unit to the retailer from which it was
purchased, without first contacting Customer Support.
Ifyou have difficulty assemblingthis product or have any
questions regardingthecontrols, operationor maintenanceof
this unit, youcan seek help from the experts.Choosefrom the
options below:
1. Visit yardman.com for many usefulsuggestions.Click
on CustomerSupport buttonandyou will get the four
options reproducedin this sampleto the right. Click on the
appropriate buttonand helpis immediatelyavailable.
2. Phonea Customer Support Representative
at 1(800)800-7310.
3. The engine manufacturer isresponsibleforall engine-
relatedissueswith regardsto performance, power-rating,
specifications,warranty and service. Pleasereferto the
engine manufacturer'sOwner's/Operator's Manual,packed
separatelywithyour unit, for more information.
Click here to search our knowledge base.
Search by product, keyword, or phrase.
Login to check the status of your questions, modify
your inquiries, or update your personal profile.
Need local assistance? Click here to find authorized
service centers in your area.
Need a manual and/or parts list? Download
literature from recent model years.
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WARNING: EngineExhaust,some of its constituents,andcertain vehicle compo-
nentscontain or emit chemicals knownto Stateof Californiato cause cancerand
birth defects or other reproductiveharm.
DANGER: This machinewas builtto beoperatedaccordingto the rulesfor safe operationin this
manual.As with anytypeof power equipment,carelessnessor error on the part of the operator can
result in seriousinjury.This machine iscapableof amputatinghands andfeet andthrowing objects.
Failureto observethe followingsafetyinstructionscould result in serious injury or death.
WARNING
Thissymbolpoints
out importantsafety
instructionswhich,if
notfollowed,could
endangerthe personal
i safetyand/or property
I ofyourselfandothers.
Readandfollowall
instructionsinthis
manualbeforeat-
temptingto operate
i this machine.Failure
I to complywiththese
instructionsmayresult
i inpersonalinjury.When
youseethis symbol.
i HEED ITS WARNING!
Your Responsibility
Restrictthe use
ofthis powermachine
to personswho read,
_understand
ano followthe warnings
and instructions
inthis manual
and on the machine.
Children
Tragicaccidentscanoccurifoperatorisnotalertto presence
ofchildren.Childrenareoftenattractedtomowerandmowing
activity.Theydonot understandthe dangers.Neverassume
thatchildrenwill remainwhereyoulastsawthem.
1. Keepchildrenoutof the mowingareaandunderwatchful
careof a responsibleadultotherthanthe operator.
2. Bealert andturn moweroff if a childentersthearea.
3. Beforeandwhilemovingbackwards,lookbehindanddown
forsmallchildren.
4. Useextremecarewhenapproachingblindcorners,
doorways,shrubs,trees,or otherobjectsthatmayobscure
yourvisionofachild whomayrunintothe mower.
5. Keepchildrenawayfromhotorrunningengines.Theycan
sufferburnsfroma hotmuffler.
6. Neverallowchildrenunder14yearsoldto operateapower
mower.Children14yearsoldandovershouldreadand
understandoperationinstructionsandsafetyrulesinthis
manualandshouldbetrainedandsupervisedbya parent.
General Operation
1. Readthis operator'smanualcarefullyin its entiretybefore
attemptingtoassemblethismachine.Read,understand,
andfollowall instructionsonthemachineandin the
manual(s)beforeoperation.Becompletelyfamiliarwith
thecontrolsandthe properuseofthis machinebefore
operatingit.Keepthis manualin asafeplaceforfuture
andregularreferenceandfor orderingreplacementparts.
2. Thismachineisaprecisionpieceof powerequipment,
nota plaything.Therefore,exerciseextremecautionat all
times.Yourunithas beendesignedto performonejob: to
mowgrass.Do notuseitfor anyotherpurpose.
3. Neverallow childrenunder 14yearsoldto operatethis
machine.Children14yearsoldand overshould readand
understandthe instructionsinthismanualandshould
betrainedand supervisedbya parent.Onlyresponsible
individualswhoarefamiliarwiththeserulesofsafe
operationshouldbeallowedto usethis machine.
4. Thoroughlyinspectthe areawherethe equipmentisto
beused.Removeallstones,sticks,wire,bones,toys
andotherforeignobjects,whichcouldbetrippedoveror
pickedupandthrownbytheblade.Thrownobjectscan
causeseriouspersonalinjury.Planyour mowingpattern
toavoiddischargeofmaterialtowardroads,sidewalks,
bystandersandthe like.Also,avoiddischargingmaterial
againsta wall or obstruction,whichmaycausedischarged
materialto ricochetbacktowardthe operator.
5. Tohelpavoidbladecontactorathrownobjectinjury,
stayinoperatorzone behindhandlesand keepchildren,
bystanders,helpersandpetsatleast75feetfrom mower
whileitis inoperation.Stopmachineifanyoneenters
area.
6. Alwayswearsafetyglassesor safetygogglesduringopera-
tionandwhile performinganadjustmentor repairto protect
youreyes.Thrownobjectswhichricochetcancauseserious
injurytothe eyes.
7. Wearsturdy,rough-soledworkshoesand close-fitting
slacksandshirts. Shirtsand pantsthatcoverthe armsand
legsandsteel-toedshoesarerecommended.Neveroperate
thismachinein barefeet,sandals,slipperyorlight-weight
(e.g.canvas)shoes.
8. Do notputhandsorfeet nearrotatingpartsor undercutting
deck.Contactwithbladecanamputatehandsandfeet.
9. A missingor damageddischargecovercancauseblade
contactor thrownobject injuries.
10.Manyinjuriesoccuras a resultofthemowerbeing pulled
overthefoot duringa fall causedbyslippingor tripping.
Do notholdontothe mowerifyouarefalling;releasethe
handleimmediately.
11.Neverpullthe mowerbacktowardyouwhileyouare
walking.Ifyoumust backthe mowerawayfroma wallor
obstructionfirstlookdownandbehindtoavoidtrippingand
thenfollowthesesteps:
a. Stepbackfrommowertofullyextendyourarms.
b. Besure youarewellbalancedwithsurefooting.
c. Pullthe mowerbackslowly,no morethan half way
towardyou.
d. Repeatthesestepsas needed.
12.Donotoperatethe mowerwhileunderthe influenceof
alcoholordrugs.
13.Donotengagetheself-propelledmechanismon unitsso
equippedwhilestartingengine.
14.Thebladecontrolhandleisasafetydevice.Neverattempt
tobypassitsoperation.Doingso makesthe safetydevice
inoperativeandmayresult in personalinjurythrough
contactwiththe rotatingblade.Thebladecontrolhandle
mustoperateeasily in bothdirectionsandautomatically
returntothe disengagedpositionwhenreleased.
15.Neveroperatethe mowerinwetgrass.Alwaysbesureof
yourfooting. A slipandfall cancauseseriouspersonal
injury.If youfeelyouarelosingyourfooting,releasethe
bladecontrolhandleimmediatelyand the bladewillstop
rotatingwithinthreeseconds.
16.Mowonlyin daylightor goodartificiallight.Walk,neverrun.
17.Stopthe bladewhencrossinggraveldrives,walksor roads.
18.Iftheequipmentshouldstartto vibrateabnormally,stopthe
engineandcheckimmediatelyforthe cause.Vibrationis
generallya warningoftrouble.
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19.Shuttheengineoff andwait untilthebladecomesto a
completestopbeforeremovingthegrasscatcheror unclog-
ging thechute.
The cuttingbladecontinuesto rotatefor a fewsecondsafter
the engineisshutoff.Neverplaceany partofthe bodyin
the bladearea untilyou are surethe blade hasstopped
rotating.
20. Neveroperatemowerwithoutpropertrail shield,discharge
cover,grasscatcher,bladecontrolhandleor othersafety
protectivedevicesin placeandworking.Neveroperate
mowerwithdamagedsafetydevices.Failuretodo so can
resultin personalinjury.
21. Mufflerandenginebecomehotandcan causeaburn.Do
nottouch.
22.Onlyusepartsand accessoriesmadeforthis machineby
manufacturer.Failuretodo so canresultinpersonalinjury.
23. Ifsituationsoccurwhicharenotcoveredinthis manual,
usecareand goodjudgment.Contactyourdealerfor
assistance.Telephone1-800-800-7310forthe nameofyour
nearestdealer.
Slope Operation
Slopesare amajorfactorrelatedto slipandfallaccidents,which
can resultinsevereinjury.Operationonslopesrequiresextra
caution.Ifyoufeeluneasyona slope,do notmowit.Foryour
safety,usetheslopegaugeincludedaspartof this manualto
measureslopesbeforeoperatingthis unitonaslopedor hilly
area.Iftheslopeisgreaterthan 15degrees,donot mowit.
Do:
1. Mowacrossthefaceof slopes;neverupanddown.Exercise
extremecautionwhenchangingdirectiononslopes.
2. Watchfor holes,ruts,rocks, hiddenobjects,or bumpswhich
can causeyouto slipor trip.Tallgrass canhideobstacles.
3. Alwaysbesureofyourfooting.A slip andfallcancause
seriouspersonalinjury.Ifyoufeelyouare losingyour
balance,releasethebladecontrolhandleimmediately,and
the bladewill stoprotatingwithin 3seconds.
Do Not:
1. Donot mowneardrop-offs,ditchesorembankments,you
could loseyourfootingorbalance.
2. Donot mowslopesgreaterthan 15degreesasshownon
the slopegauge.
3. Donot mowon wetgrass.Unstablefootingcouldcause
slipping.
Service
Safe HandlingOf Gasoline:
1. To avoidpersonalinjury orpropertydamageuseextreme
care inhandlinggasoline.Gasolineisextremelyflammable
andthevaporsareexplosive.Seriouspersonalinjurycan
occurwhengasolineisspilledonyourselforyourclothes,
whichcanignite.
2. Wash yourskin andchangeclothesimmediately.
3. Useonlyanapprovedgasolinecontainer.
4. Neverfill containers insideavehicleoron a truckortrailer
bedwitha plasticliner.Alwaysplacecontainersonthe
groundawayfromyourvehicle beforefilling.
5. Removegas-poweredequipmentfromthe truck ortrailer
andrefuelit onthe ground.Ifthis is notpossible,thenrefuel
suchequipmenton a trailerwitha portablecontainer,rather
thanfroma gasoline dispensernozzle.
6. Keepthenozzlein contactwiththe rimofthefueltankor
containeropeningat alltimesuntil fuelingis complete.Do
notuseanozzlelock-opendevice.
7. Extinguishallcigarettes,cigars, pipesandothersources
ofignition.
8. Neverfuel machineindoorbecauseflammablevaporswill
accumulatein thearea.
9. Neverremovegascap oraddfuelwhileengineishot or
running. Allowengineto coolatleasttwo minutesbefore
refueling.
10.Neveroverfillfueltank.Filltankto nomorethanY2inch
belowbottomoffiller neckto providefor fuelexpansion.
11.Replacegasolinecap andtightensecurely.
12.Ifgasolineis spilled,wipeitoff theengineandequipment.
Moveunitto anotherarea.Wait5minutesbeforestarting
engine.
13.Neverstorethe machineorfuel containernearanopen
flame,sparkor pilot lightasona waterheater,space
heater,furnace,clothesdryeror othergasappliances.
14.Toreducefire hazard,keepmowerfreeof grass,leaves,
orotherdebrisbuild-up.Cleanupoil orfuelspillageand
removeanyfuel soakeddebris.
15.Allowa mowertocool at least5 minutesbeforestoring.
GeneralService:
1. Neverrunanengineindoorsorina poorlyventilatedarea.
Engineexhaustcontainscarbonmonoxide,anodorlessand
deadlygas.
2. Beforecleaning,repairing,orinspecting,makecertainthe
bladeandall movingpartshavestopped.Disconnectthe
sparkplugwireandgroundagainstthe engineto prevent
unintendedstarting.
3. Checkthebladeandenginemountingboltsatfrequent
intervalsfor propertightness.Also,visuallyinspectbladefor
damage(e.g.,bent,cracked,worn)Replacebladewiththe
originalequipmentmanufacture's(O.E.M.)bladeonly,listed
inthismanual."Useof partswhichdo notmeetthe original
equipmentspecificationsmayleadto improperperformance
andcompromisesafety!"
4. Mowerbladesaresharpandcancut.Wrapthebladeor wear
gloves,anduseextracautionwhenservicingthem.
5. Keepallnuts,bolts,andscrewstightto besurethe equip-
mentis insafeworkingcondition.
6. Nevertamperwithsafetydevices.Checktheirproperopera-
tionregularly.
7. Afterstrikingaforeignobject,stopthe engine,discon-
nectthesparkplugwireandgroundagainsttheengine.
Thoroughlyinspectthemowerforanydamage.Repairthe
damagebeforestartingandoperatingthemower.
8. Neverattemptto makeawheelor cuttingheightadjustment
whiletheengineis running.
9. Grasscatchercomponents,dischargecover,andtrail
shieldaresubjecttowear anddamagewhichcouldexpose
movingpartsor allowobjectsto bethrown.Forsafety
protection,frequentlycheckcomponentsandreplaceim-
mediatelywithoriginal equipmentmanufacturer's(O.E.M.)
partsonly,listedinthis manual."Useofpartswhich do
notmeetthe originalequipmentspecificationsmayleadto
improperperformanceandcompromisesafety!"
10.Donotchangetheenginegovernorsettingor over-revthe
engine.Thegovernorcontrolsthe maximumsafeoperating
speedoftheengine.
11.Maintainorreplacesafetylabels,asnecessary.
12.Observeproperdisposallawsand regulations.Improper
disposaloffluidsand materialscanharmtheenvironment.
Operation
WARNING
Thissymbol points
out importantsafety
instructions,which if
notfollowed,could
endangerthe personal
safety and/or property
of yourselfand others.
Readand followall
instructions inthis man-
ual before attemptingto
operatethis machine.
Failureto comply with
these instructionsmay
result in personalinjury.
Whenyou seethis
symbol.
HEED IT'S WARNING!
YourResponsibility
Restrictthe use
of this powermachine
to personswho read.
understand
and followthe warnings
and instructions
in this manua
and on the machine.
5