Toro TRX-250 - Replacing the Drive Sprocket

8.Torquethe2boltsandnutssecuringtheboom
to183to223N∙m(135to165ft-lb).
ReplacingtheDrive
Sprocket
Overtime,thedrivesprocketwears,especiallywhen
itisusedinsandyorclaysoils.Whenthishappens,
thediggingchainbeginstoslip.Ifthechainslips,
replacethedrivesprocketasfollows:
1.Parkthemachineonalevelsurface,engage
theparkingbrake
2.Raisethetrencherafewinchesabovethe
ground.
3.Shutofftheengineandremovethekey.
4.Removethespoilsauger(Figure63).
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Figure63
1.Spoilsauger
2.Bolts
3.Drivesprocket
4.Sprocketmountingsurface
5.Loosenthe2boltsandnutssecuringtheboom
tothetrencherarm.
6.Loosenthejamnutontheadjustingboltinthe
boom.
7.Loosentheadjustingboltuntilyoucanremove
thechainfromtheboom.
8.Removethechainfromthedrivesprocket.
9.Removethe6boltssecuringthedrivesprocket
(Figure63).
10.Removeanddiscardthedrivesprocket(Figure
63).
11.Cleanthesprocketmountingsurfaceonthe
trencher(Figure63).
12.Slidethenewsprocketontotheshaft(Figure
63).
Important:Thearrowonthesprocketface
shouldbevisiblefromtherightsideof
thetrenchandshouldpointinaclockwise
direction;ifnot,turnthesprocketaround.
13.Threadthe6boltsintothesprocketngertight
(Figure63).
14.Slowlybegintighteningtheboltsprogressing
aroundthesprocketuntilallboltsaretorquedto
129to155N∙m(95to115ft-lb).
Important:Tighteneachboltonlyhalfway
rst,workingyourwayaroundthe6bolts,
thenreturntoeachboltinturnandtorque
them
15.Loopthechainovertheaugerdriveshaftand
ontothedrivesprocket,ensuringthattheteeth
pointforwardontheupperspan.
16.Settheupperspanofthechainintoplaceon
thetrencherboom,thenwrapthechainaround
therollerattheendoftheboom.
17.Threadtheadjustmentboltintotheboomand
turnitinuntilthereis3.8to6.3cm(1-1/2to2-1/2
inches)ofslackinthechainonthebottomspan.
18.Threadthejamnutdowntheadjustingboltand
tightenitsecurelyagainsttheboom.
19.Torquethe2boltsandnutssecuringtheboom
to183to223N∙m(135to165ft-lb).
20.Installthespoilsaugerusingtheboltandnut
youremovedpreviously.
Note:T orquetheboltandnutto102N∙m(75
ft-lb).
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