Navistar International LT Series User Manual

Operation
BrakeApplication
Rapidsuccessivebrakeapplicationsandrelease,sometimes
referredtoasfanningorpumpingthepedal,shouldbeavoided.
Thisisaninefcientwayofslowingorstoppingavehicle
andinefcientuseofairpressure.Italsodefeatstheproper
operationoftheABS.
ParkingBrake
WARNING
Topreventpersonalinjuryand/ordeath,or
damagetoproperty,undernocircumstances
shouldthespringbrakesectionofthespring
andservicebrakechamberbedisassembled.
Disassemblywillreleaseapowerfulspring.
Allvehicleswithairbrakesareequippedwithspringbrake
chambersforparking.Theparkingsystemisoperatedmanually
byasinglevalve,whichinthecaseofatractoralsocontrolsthe
parkingsystemonthetrailer.
Thepurposeofthisbrakeistoholdthevehicleinaparked
position.Theparkingbrakeshouldnotbeusedtobrakethe
vehicleduringnormaldriving.
Toapplytheparkingbrake,pulloutcontrolknob.T oreleasethe
parkingbrake,pushinthecontrolknob.
Itshouldbenotedthatuponlossofairpressureinbothprimary
andsecondarysystems,partialspringbrakeapplicationwill
occurpriortofullautomaticapplicationoftheparkingbrake
controlvalveat20-45psi(138-310kPa).
Toreleasetheparkingbrakeafteralow-pressureoccurrence,
rechargesystemtoatleast70psi(483kPa)andpushinthe
parkingbrakecontrol.Ifthesystemcannotberechargedand
thevehiclemustbemoved,thespringbrakemustbemanually
released(caged).
WARNING
Topreventpersonalinjuryand/ordeath,or
damagetoproperty:
•Alwaysinstallwheelchockswhenmanually
releasingtheparkingbrake,orthevehiclecan
roll.
•Fortowing,makesurethevehicleissecurely
connectedtotowvehicleandtowvehicle
parkingbrakeisappliedbeforereleasingthe
disabledvehicle’sparkingbrake.
•Toensurereleaseofparkingbrake,alwayscage
thespringinthebrakechamber.
•Undernocircumstancesshouldthespring
brakechamberbedisassembledforthepurpose
ofreleasingtheparkingbrake.
Ifitisnecessarytomovethevehicleafteranemergency
application(beforeairpressurecanberestored),theparking
springcanbecompressedmechanicallytoreleasethebrake.
Areleasestudspringcagingtoolisfurnishedwiththebrake
chamberassembly.Thereleasestudengagesinthespring
pressureplateanditsnutistightenedtocompress,cagethe
spring,andreleasethebrake.
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Navistar International LT Series Specifications

General

Brand	Navistar
Model	International LT Series
Category	Trucks
Language	English