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FormNo.3416-597RevA
18inStraight-ShaftGasTrimmer
ModelNo.51978A—SerialNo.317000001andUp
Registeratwww.T oro.com.
OriginalInstructions(EN)
*3416-597*A
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OrderingReplacementParts
Toorderreplacementparts,pleasesupplythepartnumber,
thequantity,andthedescriptionofeachpartdesired.
UnderstandingReferenceNumbers
Eachidentiedpartinanillustrationhasareference
number.Thereferencenumberforapartalsoappearsin
thepartslist,alongwithotherinformationaboutthepart.
Thiscatalogusestwospecialreferencenumberformats,
onetoindicatepartsinaserviceassemblyandanotherto
indicatethequantityofagivenpartinanillustration.
ServiceAssemblyReferenceNumbers
Partsinserviceassemblieshavereferencenumbersinthe
forma:b.Thearepresentsthereferencenumberofthe
entireserviceassemblyandthebrepresentsasequential
numberuniquetoeachpartwithintheserviceassembly.
Forexample,awheelassemblymightbeidentiedby
referencenumber6,thetireby6:1,thevalveby6:2,and
thewheelby6:3.Whenyouordertheassemblyidentied
byreferencenumber6,youreceiveallpartsidentiedby
referencenumbers6:1,6:2,and6:3.However,youmay
alsoorderanypartindividually .Referencenumbersofthis
typeappearinillustrationandinpartslists.
ReferenceNumbersIndicatingQuantity
Inanillustration,ifareferencenumberindicatesmorethan
onepart,thereferencenumberhastheformnXy .Then
representsthequantityofthepart,theXisthemultiplication
symbol,andtheyrepresentsthereferencenumber.
Forexample,inanillustration,thereferencenumber2X37
meansthattwoofthepartsidentiedbyreferencenumber
37areindicated.
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Contents
TrimmerHead,ShaftandGuardAssembly.....................................................................4
UpperShaft,HandleandPowerheadAssembly.................................................................6
PowerHeadComponentsAssembly...........................................................................8
AttachmentsandAccessories...............................................................................10
©2017—TheToro®Company
8111LyndaleAvenueSouth
Bloomington,MN55420
Contactusatwww.Toro.com.
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AllRightsReserved
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TrimmerHead,ShaftandGuardAssembly
3416-597A402