Case 621G - Page 210

7-MAINTENANCE
Hourmeter
Thehourmeterenablesserviceoperationstobesched-
uled.Itshourlyindicationsarethesameasthoseofa
clockwhentheengineisrunning.
Servicingintervalsarecarefullycalculatedtoguarantee
safeandefcientmachineoperation.
Besuretocarryoutalltheservicingoperationsproperly
asdenedinthismanual.
Variableperiodicmaintenance
Someworkingenvironmentsrequirethatmaintenancebeperformedmorefrequently.T akeintoconsiderationdust,
dirt,moisture,extremehotorcoldandmanyotherfactorswhenservicingthemachine.Certainequipmentorauxiliary
toolsmaycausemorestressonhydraulics,drivetrain,enginesorlters.Performthefollowingmaintenanceonregular
schedules,butmaintenanceoftenneedsspecialattentionwhenconditionssorequire.
Engineairlter
Replacetheprimaryelementiftheairlterindicatorlamp
illuminates.
Theprimaryelementmaybecleaned,howeveranew
elementisrecommended.Theinnerelementcannotbe
cleanedandmustbereplaced.
Tocleantheprimaryairlter,holdwiththerubberseal
facingup.Tapallsidesofthelterwithyourhand.Blow
thelteroutwithcompressedair—maximumpressure
4.8bar(70psi).Holdthenozzleaminimumof7.6cm
(3in)awayfromlter.Useanozzlediameternosmaller
than6.4mm(0.25in).Inspectthelterfordamage.
Wipetheltersealoffandcleanalldustfromaircleaner
housing.Neverusewatertocleantheprimarylter.
Tiresandwheels
Adjusttheinationpressureofthetireswhencircum-
stancesrequire.Keepthetiresproperlyinatedand
checkthetorqueofthewheelbolts/studs.
Checkthewheelsforpropertorqueeverytwentyhours
whennewanduntilthewheelsremaintight.
Airconditioningcondenser
Theairconditioningcondenserislocatedinthecooling
boxattherearofthemachine.Usecompressedairto
removedebrisandbuilduponthecondenser.
Fuelcooler
Thefuelcoolerislocatedinthecoolingboxattherearof
themachine.Usecompressedairtoremovedebrisand
buildupthatmayimpedeproperfunctionofthecooler.
Fuelpre-lter
Raisetheenginehoodanddrainwaterandsedimentfrom
thefuelpre-lter.Removeelectricalconnectors.Slowly
loosenthedrainvalvelocatedunderthepre-lteruntil
cleanfuelrunsout.
Retightenthevalveandreplacetheelectricalconnectors.
Donotovertightenvalve.Thisprocedureshouldbea
periodicmaintenanceproceduredependentuponclimate
anduseconditions.Seethecompleteprocedureforthe
fuelpre-lterandfuellterinthissection.Usethebleed
screwonthelterhousingtoreleaseairfromthefuel
system.
Primingthefuelsystem
Prolongedperiodofinactivityorrunningoutoffuelmay
allowairtogetintothefuelsystem.Ifthisshouldhappen
makesurethetankisfullandthenprimethesystemusing
themanualprimingpumponthefuelpre-lter.
Fuses
Opentheaccesspanellocatedinsidethecab,behindthe
operator’sseat,toreachthefuses.Ifafusehasblown
theindicatorlightwillilluminate.
NOTE:ifafuseblows,replacethefuseatonce.Locate
theproblemandifitreoccurs,haveitcheckedbyaser-
vicetechnician.
7-2