TUG GT-50DZ User manual

Operation, Maintenance, and Parts Manual
MODEL
GT-50DZ
"TOW TRACTOR
WITH DEUTZENGINE
Aircraft Ground Support Equipment CD274
produced by
m_lIKETIIll _EIVlCE$
Ti_TALm Jlrum_wi

STEWART &STEVENSON SERVICES, INC. FRONT MATI'ER
AIRCRAFTGROUND SUPPORT EQUIPMENT
RECORD OFREVISIONS
PROPERTY OF:
COMPANY:
ADDRESS:
CITY STATEZIPCODE
REVISION DATA
CHECK EACHREVISION RECEIVED, AND INSERT THEREVISED AND SUPPLEMENTARY
PAGESIN YOUR. MANUAL.
DATE OF ORIGINAL PUBLICATION: AUGUST 1994
REVISION DATE
1 October ]994
2November 1994
3 December 1994
4March1995
5 March1997
6
7
CD274 i
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STEWART & STEVENSON SERVICES, INC. FRONT MAI-I.Va¢.
AIRCRAFTGROUND SUPPORT EQUIPMENT
LIST OF EFFECTIVE PAGES
Title Page Orig MI02007-1 and MI02007-2 Orig
Record of Revisions-i Rev 5 MI02008-1 and MI02008-2 Orig
Listof EffectivePages-iiand iii Rev5 MI02008-3 RevI
Manual Table of Contents-ivthin x Rev 3 MI02008-4 Orig
List of Figures-xi thin xiii Rev 3 MI02009-1 and MI02009-2 Orig
List of Tables-xiv Rev 3 MI02009-3 Rev 1
Introductlon-xv Rev 3 MI02009-4 Ofig
Unit Idenfification-xv Rev 3 MI02010-1 and MI02010-2 Orig
Technical Assistance-xvi Rev 3 MI02010-3 Rev 1
Safety Precautions-xvii Rev5 MI02010-4 Orig
How To Use This Manual-xviii Rev 3 MI02011-1 and MI0201I-2 Orig
MI02011-3 Rev1
CHAPTER 1 MI02011-4Orig
I-TOC-ithra 1-TOC-iv (3rig MI03006-1 thru MI03006-4 Orig
1-1-1 thin I-1-4 Rev 1 MI03007-I and MI03007-2 Rev 1
1-1-5 thin 1-1-12 Orig MI03008-1 thru MI03008-6 Orig
l-2-1 and 1-2-2 Orig MI03009-1 and MI03009-2 Orig
1-2-3 and 1-2-4 Rev 1 MI04007-1 Orig
1-2-5 Orig MI04007-2 Rev2
1-2-6 Rev I MI04009-1 and MI04009-2 Rev 2
1-2-7 Rev3 MI04010-1 and MI04010-2 Orig
1-2-8 Rev 1 MI06003-1 Rev 3
1-2-9 Rev 3 MI06003-2 thin MI06003-4 Orig
1-2-10 Rev 1 MI08004-1 Orig
1-2-11 Rev 3 MI08004-2 Rev 1
1-2-12 Rev 1 MI08005-1 Orig
I-2-13 Rev 3 MI08005-2 Rev 1
I-2-14 RevI MI09012-1thraMI09012-4 Orig
1-3-1 and 1-3-2 Rev 3 MII2001-1 Rev 1
1-3-3 Rev 2 MI12001-2 Orig
1-3-3 Rev 2 M/99003-1 and MI99003-2 Orig
1-3-4 Orig MI99003-3 Rev4
1-3-5Rev I MI99003-4 Orig
1-3-6 thin 1-3-9 Rev 3 M199003-5 Rev 4
1-3-10 Rev1 MI99003-6 Rev1
1-4-1 thra 1-4-4 Ofhg MI99004-1 thru MI99004-4 Rev 4
1-5-1 0fig
I-5-2 Rev I CHAPTER 3
1-5-3thru1-5-6 Orig 3-TOC-iand3-TOC-ii Orig
3-1-1 Rev1
CHAPTER 2 3-1-2 Orig
2-TOC-i and 2-TOC-ii Orig 3-2-1 Rev 4
2-1-1 Rev 5 3-2-2 thra 3-2-8 Orig
2-1-2 thin 2-1-4 0fig
2-2-1 and 2-2-2 Ofig CHAPTER 4
2-2-3 and2-2-4 Rev 44-TOC-i Orig
2-2-5 and 2-2-6 Orig 4-TOC-ii Rev 1
2-2-7 Rev 5 4--1-1 thin 4-1-4 Drig
2-2-8 thin 2-2-10 Orig 4-2-1 Rev 4
2-3-I thru 2-3-4 Orig 4-2-2 Orig
4-3-1 and 4-3-2 Orig
MI01004-1 Orig 4-3-3 thru 4-3-10 Rev 3
MI01004-2 Rev 1 4-3-11 Rev 2
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STEWART & STEVENSON SERVICES, INC. FRONT MArIER
AIRCRAFT GROUND SUPPORT EQUIPMENT
LIST OF EFFECTIVE PAGES
4-3-12 Rev3 CHAPTER5
4-3-13thra4-3-15 Rev2 5-TOC-i Rev4
4-3-16 Rev3 5-TOC-ii Orig
4-3-17thru4-3-22 Rev2
4-3-23 Rev3 CHAFIER6
4-3-24 Rev2 6-TOC-i Orig
44 1thin443 Orig 6-TOC-ii Rev2
444 Rev4
4 g 5 and 4-4-6 Rev 3 OPTION 1
4_7 Orig 6-1-1 Rev4
4 4 8thin 4-4-10 Rev 3 6-1-2 Orig
4-4-11 thin 4-4-20 Orig 6-1-3 thru 6-1-9 Rev 4
4-4-21 Rev3 6-1-10 Orig
4-4-22 Rev4
4-4-23 Rev3 OPTION2
4-4-24 Rex"4 6-2-1 Orig
4 4 25 Rev 3 6-2-2 Rev4
4 4 26 thru 4-4-39 Orig 6-2-3 and 6-2-4 Orig
4-4-40thru 4-4-40B Rev 4
4-4-41 Orig INDEX-1 thin INDEX-4 Orig
4_442and44 43 Rev3
4-4-44thru4-4-47 Orig
44 48 and 4449 Rev3
4-4-50 thru4-4-59 Orig
4.4 60thru4-4-63 Rev3
4-4-64 Rev 2
d4.65 Rev3
4-4-66 thru 4-4-69 Orig
44 70and4 471 Rev3
4472 Orig
4, el73 Rev 3
4"!.74 thru 4-4-80 Orig
4-4-81 Rev 3
4-4-82 Orig
4-4-83 Rev 3
"!.4 84 Rev 4
4-4-85 thru 4-4-94Deleted
12941092 (4sheets) Rev A
4-4-95 thru 4-4-98Orig
4-4-99thru4 4 102 Rev1
44103 Rev2
4-4-104 thru 4-!.107 RevI
4-4-108 Rev4
12941675(2 sheets) RevA
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STEWART & STEVENSON SERVICES,INC. FRONT MAJtbR
AIRCRAFT GROUND SUPPORT EQUIPMENT
MANUAL TABLE OF CONTENTS
DESCRIPTIONCHAPTER/SECTION/PAGE
Record of Revisions Front Matter/i
L'rst of Effective Pages FrontMatter/ii
Manual Table of Contents Front Matter/'lii
List of Ftgures Front Matterflx
Listof Tables Front Matter/xii
Imroduction FrontMatter/xiii
Unit Identification FrontMatter/xiii
Technical Assistance Front Matter/xiv
Safety Precautions Front M_nar/xv
How to Use This Manual Front M_ner/xvi
CHAPTER 1 GENERAL INFORMATION AND OPERATING INSTRUCTIONS
SECTION 1 GENERAL DESCRIPTION ..................................... I-1-1
1.1INTRODUL-i_ON ............................................. 1-1-1
1.2 UNIT DESCRIPTION .......................................... 1-t-I
1.3 ENGINE ................................................... 1-1-3
1.4TRANSMISSION ............................................. 1-1-3
1.5 DRIVE LINE ASSEMBLY...................................... 1-1-3
1.6 FUEL SYSTEM .............................................. 1-1-3
1.7 AIRINTAKESYSTEM ........................................ 1-1-4
1.8 EXHAUST SYSTEM .......................................... 1-1-4
1.9 LUBRICATION SYSTEM ....................................... 1-1-4
1.10 COOLING SYSTEM .......................................... 1-1-4
1.11 STEERING SYSTEM .......................................... 1-1-4
1.12 BRAKE SYSTEM ............................................ 1-1-6
1.12.5Parking Brake ............................................... 1-1-9
1.13 LIFTCAB (OPTIONAL) ....................................... 1-1-9
1.14 _.IF_-t RICAL SYSTEM. ....................................... 1-1-9
1.14.2 Engine Starting and Battery Charging Circuits ........................ 1-1-10
1.14.3 Brake Booster Motor Circuit. ................................... 1-1-I0
1.14.4 Engine RunRelay Circuit. ..................................... 1-1-10
1.14.5 HornCircu'rt................................................ 1-1-10
1.14.6 EnginelnsmmaentCircuit. ..................................... 1-1-10
1.14.7 Light Circuit. .............................................. 1-1-10
1.14.8 WarningLight Circuit. ........................................ 1-1-11
1.14.9 Auxiliary Light Circuit. ....................................... I-1-11
1.14.11Engine Coolant Heater (Optional) ................................. 1-1-12
1.14.12 Engine Fuel]Water Separatorand Fuel Heater(Optional) ................. 1-1-12
1.14.13 Cab Circuits (Optional) ........................................ 1-1-12
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AIRCRAFr GROUND SUPPORTEQUIPMENT
MANUAL TABLE OF CONTENTS (CONT.)
DESCRIPTION CHAPTER/SECTION/PAGE
SECIION 2OPERATION ............................................... 1-2-1
2.1 PRE-OPERATIONAL CHECKS .................................. 1-2-1
2.2 OPERATING PROCEDURES .................................... 1-2-3
2.3 SHUTDOWN PROCEDURE ...... .,.............................. 1-2-4
2.4 CONTROLS AND INDICATORS ................................. 1-2-7
SECTION 3 SPECIFICATIONS .......................................... 1-3-1
3.1 INTRODUCI'ION ............................................ 1-3-1
3.2 SPECIFICATION TABLES ..................................... 1-3-1
3.3 POINTS OF SERVICE, SPECIFICATION, AND CAPAISITL_S............ 1-3-4
SECTION 4 SHIPPING ................................................. 1-4-1
4.1 INTRODUCTION............................................. 1-4-1
4.2 TUzDOWN POINTS .......................................... 1-4-1
4.3 LII'TING ................................................... 1-4-1
4.4 PREPARING ENGINE ......................................... 1-4-1
4.5 PREPARING UNIT ........................................... 1-4-2
4.5.1 Batteries................................................... 1-4-2
4.5.2 Windshields(Cab Option Only)................................... 1-4-2
4.5.3 Control Panel (Without Cab Option Only) ............................ 1-4-2
4.5.4 WarningBeacons............................................. 1-4-2
4.6 MARKING ................................................. 1-4-2
4.7 RECEIVING EQUIPMENT ...................................... 1-4-2
4.7.1 Inventory................................................... 1--4-2
4.7.2 _on .................................................. 1-4-2
4.7.3 Notification................................................. 1-4-2
4.8 PREPARING UNIT FOR SERVICE ................................ 1-4-2
4.8.1 Windshields(Cab Option Only)................................... 1-4-2
4.8.2 Warningbeacon(s)............................................ 1-4-2
4.8.3 Air Cleaner................................................. 1-4-3
4.8.4 Batteries................................................... 1--4-3
4.8.5 Engine..................................................... 1-4-3
4.8.6 ControlPanel (Without Cab OptionOnly)............................ 1-4-3
4.8.7 Markings................................................... 1-4-3
SEuIION 5 STORAGE ................................................. 1-5-1
5.1 SHORT-TERM STORAGE ...................................... 1-5-1
5.1.1 Engine..................................................... 1-5-1
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AIRCRAFTGROUND SI.YPPORT EQUIPMENT
MANUAL TABLE OF CONTENTS (CONT.)
DESCRIPTION CHAPTER/SECTION/PAGE
5.1.2 Transmission ................................................ 1-5-1
5.1.3 Drive Axles ................................................. 1-5-1
5.1.4Tires ...................................................... I-5-1
5.1.5 Batteries ................................................... 1-5-1
5.2 RETURN TRACTOR TO OPERATION Al--tv_,RSHORT-TERM STORAGE... 1-5-1
5.2.1 Tires...................................................... 1-5-1
5.2.2 Batteries ................................................... 1-5-2
5.2.3 Engine..................................................... 1-5-2
5.2.4 Transmission ................................................ 1-5-2
5.3 LONG-TERM STORAGE ....................................... 1-5-2
5.3.1 Engine..................................................... 1-5-2
5.3.2 Batteries ................................................... 1-5-4
5.3.3 Driveaxles................................................. 1-5-4
5.3.4 Transmission................................................ 1-5-4
5.3.5 Tires...................................................... 1-5-4
5.3.6 Windows (Cab Option Only) ..................................... 1-5-4
5.4 RETURN TRACTOR TO OPERATION A.t--t__&LONG-TERM STORAGE .... 1-5-4
5.4.1 Tires...................................................... 1-5-4
5.4.2 W'mdows(CabOptionOnly)..................................... 1-5-5
5.4.3 Batteries .................................................... 1-5-5
5.4.4 Engine..................................................... 1-5-5
5.4.5 Transmission................................................ 1-5-5
5.4.6 Driveaxles................................................. 1-5-5
CHAPTER 2 MAINTENANCE
SECTION 1 PREVENTIVE MAINTENANCE SCHEDULE ........................ 2-1-1
1.1 /NTRODUcq iON ............................................ 2-1-1
1.2 HOW TO USE THE PREVEN'HVE MAINTENANCE SCHEDULE ........ 2-1-1
SECTION 2 TROUBLESHOOTING ........................................ 2-2-1
2.1 INTRODU Ci'J.ON ............................................ 2-2-1
2.2 HOW TO USE THE TROUBLESHOOTING TABLES ................... 2-2-1
2.3 OBTAINING FACTORY ASSISTANCE ............................ 2-2-1
SECTION 3 MAINTENANCE INSTRUCTIONS ............................... 2-3-1
3.1 INTRODUCTION ............................................. 2-3-1
3.2 HOW TOUSE THE MAINI'f=NANCE INSTRUCTIONS(MI) ............. 2-3-1
3.3 LISTOFEVt"t_C-IiV'E MAINTENANCE INSTRUCTIONS............... 2-3-2
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STEWART & STEVENSON SERVICES,INC. FRONT MATI_R
AIRCRAFT GROUND SUPPORTEQUIPMENT
MANUAL TABLE OF CONTENTS (CONT.)
DESCRIPTION CHAPTER/SECTION/PAGE
CHAPTER 3 OVERHAUL
SECTION1 OVERHAUL DATA .,........................................ 3-1-1
1.1 MODEL GT-50DZ TOW TRACTOR OVERHAUL ............. ......... 3-1-1
1.2 ENGINE................................................... 3-1-t
1.3 TRANSMISSION ............................................. 3-1-1
1.4 AXL_-S.................................................... 3-1-1
SECTION2 REMOVAL AND INSTATJ.ATION ............................... 3-2-1
2.1 ENGINEANDTRANSMISSION ASSEMBLY REMOVAL ............... 3-2-1
2.2 ENGINE AND TRANSMISSION ASSEMBLY INSTAT.T.ATION
PROCEDURE_ .............................................. 3-2-4
2.3 AXIFREMOVAL PROCEDURES ................................ 3-2-4
2.4 A.,roF. ]NSTAt.r,ATION PROCEDURES ............................ 3-2-6
CHAPTER4PARTS
SECTION 1 PARTS LIST............................................... 4-1-1
1.1 INTRODUCTION ............................................. 4-1-1
1.2 PARTSLIST................................................ 4-1-1
1.2.2 Figure and Index Number Colnrnr_................................. 4-1-2
1.2.3 Part Number Cohmm.......................................... 4-1-2
1.2.4 Manufacturer's Code ........................................... 4-1-2
1.2.5 Description Column........................................... 4-1-2
1.2.6 Quantity Colnmn .............................................. 4-1-2
1.3 HOW TOLOCATEPARTS ..................................... 4-1-2
1.4 HOW TO ORDER PARTS ...................................... 4-1-3
SEt.'tlON 2 MANUFACqu-RER'S CODES ................................... 4-2-1
SECTION 3 ALPHA-NUMERIC INDEX ..................................... 4-3-1
3.1 INTRODUt_'iiON ............................................. 4-3-1
SEctlON 4GROUPINDEX............................................. 4 4 1
GROUP 1 TOW TRACTOR ASSEMBLY ................................... 4 4 3
1.1 TOW TRACTOROVER_T.t. VIEW ............................... 4 4 4
1.2 OPERATOR'S COMPARTMENT ................................. 4 4 8
1.3 CAB MODEL 416 (OPTION) ................................... 4 4 12
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AIRCRAFT GROUND SUPPORT EQUIPMENT
MANUAL TABLE OF CONTENTS (CONT.)
DESCRIPTIONCHAPTER/SECTION/PAGE
GROUP 2 DRIVE LINE .............................................. 4 4 19
2.1 ENGINE AND TRANSMISSION ASSEMBLY ...................... 4.420
2.2 ENGINE ANDTRANSMISSION CONNECTION .................... 4422
2.3 DRIVE LINE ASSEMBLY .................................... 4 4.24
2.4 STEERABLE AXLE HOUSING ................................. 4426
2.5 STEERABLE AXI.I_ DU_t-t!RENTIAL ............................ 44 28
2,6 STEERABLE AXI,I_ STEERING PARTS .......................... 44 30
2.7 STEF,RA.BLE AXLE PLANETARY HUBREDUCERS ................. 44 32
2.8 RIGID AX'IF,HOUSING ...................................... 4 4 34
2.9 RIGID AXLE DIPPP.,RENTIAL ................................. 44 36
2.10 RIGID AXI,F,PLANETARYHUBREDUCERS ...................... 4 4 38
GROUP 3 BRAKE SYSTEM COMPONENTS ............................... 4441
3.1BRAKE LINKAGE AND MASTER CYLINDER/.................... 4 4 42
HYDRAULIC BOOSTER
3.2 BRAKE HYDRAULIC BOOSTER ASSEMBLY ..................... n_, 44
3.3 BRAKE SYSTEM HYDRAULIC BOOSTER CIRCUIT ................ _ 4 "!.6
3.4 HYDRAULICBRAKESYSTEM ................................ 4 4 48
3.5 FRONT BRAKE ASSEMBLY .................................. 4 450
A,4
3.6 REARBRAKEASSEMBLY ..................................... 52
nA
3.7 PARKING BRAKE LINKAGE .................................... 54
3.8 PARKING BRAKE ASSEMBLY ................................ 44 56
GROUP 4 FUEL SYSTEM COMPONENTS ................................ 4 4 59
4.1 FUELSYSTEM WiTH FUEL FILTER/WATER ..................... 4 4 60
SEPARTOR (OPTION)
4.3 THROTILE CONTROL ...................................... 44 64
GROUP 5 GOVERNOR ADJUSTMENT (NOT USED REFER TO GROUP 4) ........ 4 4 67
GROUP 6 LUBRICATION SYSTEM FOR ENGINE AND TRANSMISSION ......... 4 4 69
6.1 TRANSMISSION LUBE OILSYSTEM ........................... 4 470
6.2 ENGINE LUBE OILSYSTEM .................................. 4 4 72
GROUP7 ENGINE COOLING SYSTEM COMPONENTS ...................... 4 4 75
7.1 ENGINE COOLING SYSTEM .................................. 4 4 76
GROUP 8 ENGINE AIR INTAKE AND EXHAUST SYSTEM ................... 4 4 79
8.1 AIR INLETASSEMBLY ...................................... 4 4 80
8.2 EXHAUST SYSTEM ......................................... 44 82
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AIRCRAFT GROUND SUPPORT EQUIPMENT
MANUAL TABLE OF CONTENTS (CONT,)
DESCRIPTION CHAPTER]SECTION/PAGE
GROUP9 r::J.F.Cq'P,ICAL SYSTEM COMPONENTS .......................... 4 4 85
9.1 OPERATOR CONTROL PANEL ASSEMBLY...................... 4-4.-86
9.2 ELECTRICAL PARTS ........................................ 4-4-90
GROUP 10 GENERATOR(NOT USED) ................................... _ 4 95
GROUP 11 NOT USED ............................................... d 4 97
GROUP 12 STEERING SYSTEM COMPONENTS ............................ _I4 99
12.1 STI=_,P,ING COLUMN ....................................... 4 4 100
12.2 HYDRAULIC STEERING VALVE ASSEMBLY .................... 4 4 102
12.3 HYDRAULIC FILTERASSEMBLY............................. d 4 104
12.4 HYDRAULIC STEERING PUMP............................... ,! _ 106
12.5 HYDRAULIC STEERING SYSTEM ............................. _ _ 108
CHAI:q'F__ 5 DRAWINGS
TABLE OF CONTENTS ..................................... 5-TOC-i
CHAPTER 6 OPTIONS AND MANUFACTURER'S DATA
TABLE OF CONTENTS ..................................... 6-TOC-i
OPTIONAL EQUIPMENT - INTRODUCTION ................... 6-INTRO-i
1. GT50 STr::_.RING OPTIONS .................................... 6-1-1
1.1 DESCRIPTION.............................................. 6-1-1
1.1.1 STI=_-RING MODES .......................................... 6-1-1
1.1.2 ACTIONOFFRONT AX[]:. .................................... 6-1-1
1.1.3 ACIION OF REAR AXLE ..................................... 6-1-1
1.2 OPERATION ............................................... 6-1-1
1.2.1 TRACK ST'_RING MODE ..................................... 6-1-1
1.2.2 COORDSTEERINGMODE " 6-1-1
1.2.3 CRAB STt_'RRING MODE ...................................... 6-1-1
1.3 MAINTV_.NANCE ............................................ 6-1-3
1.3.1 PREVENTIVE MAINTI_NANCE ................................. 6-1-3
1.3.2 TROUBLESHOOTING ........................................ 6-1-3
1.3.3 ADJUSTMENTS............................................. 6-1-3
1.5 DRAWINGS................................................ 6-1-9
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AIRCRAFT GROUND SUPPORT EQUIPMENT
MANUAL TABLE OF CONTENTS (CONT.)
DESCRIPTION CHAPTER/SECTION/PAGE
2. CAB ..................................................... 6-2-1
2.1 DESCRIPTION.............................................. 6-2-1
2.1.1 TYPES .................................................... 6-2-1
2.1.2 STANDARDCAB ........................................... 6-2-1
2.1.3 LIFTCAB ......................................... ........ 6-2-i
2.1.4 LIFT CAB HYDRAULIC SYSTEM ............................... 6-2-1
2.1.5 STANDARDCABSPECIFICATIONS............................. 6-2-1
2.1.6 LIFT CAB SPEcIi_ICATIONS .' .................................. 6-2-2
2.2 OPERATION ............................................... 6-2-2
2.2.1 Lff'1" CAB OPERATION ....................................... 6-2-2
2.2.2 CONTROLS ................................................ 6-2-2
2.3 MAINTENANCE ............................................ 6-2-2
2.3.1 PREVENTIVE MAINI_IqANCE (FOR STANDARDAND LII'.I CAB) ...... 6-2-2
2.3.2PREVENTIVE MAINI_NANCE (FOR LII-TCABONLY) ............... 6-2-3
2.4 PARTS LIST ............................................... 6-2-3
2.4.1 STANDARDCAB........................................... 6-2-3
2.4.2 HYDRAULIC LII-T CAB ....................................... 6-2-3
2.5 DRAWINGS................................................ 6-2-3
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STEWART & STEVENSON SERVICES, INC. FRONT MAI-I___R
AIRCRAFTGROUND SUPPORT EQUIPMENT
LIST OFFIGURES
CHAPTER/
FIGURE TITLE PAGE
CHAPTER 1 GENERAL INFORMATION AND OPERATING INSTRUCTIONS
1.1 MODEL GT-50C/50CH TOW TRACTOR ........................... 1-1-I
1.2 DRIVE LINE ASSEMBLY ..................................... 1-1-2
1.3 COOLING SYSTEM .......................................... 1-1-5
1.4 HYDRAULIC STF_F._NG SYSTEM SCHEMATIC .................... 1-1-7
1.5 HYDRAULIC BRAKE SYSTEM ................................. 1-1-8
2.1 OPERATOR'S PANEL AND CONTROLS (TABLE 2.2)(SHEET 1 OF 3) .... 1-2-6
2.1 OPERATOR'S PANELAND CONTKOLS (TABLE 2.2)(SHEET 2 OF 3) .... 1-2-8
2.1 OPERATOR'S PANEL AND CONTROLS (TABLE 2.2)(SHEET 3 OF 3) ... 1-2-10
3.1 SERVICING POINTS (SI'II_T 1 OF 2) ............................. 1-3-6
3.1 SERVICL'NG POINTS (SHEET 2 OF 2) ............................. 1-3-8
CHAPTER 2 MAINTENANCE
1. S'I'PJP;RINGASSEMBLY AND DRIVESHAFTS SERVICING POINTS .. MI02008-2
1. AXLE AND WI'_.F_L END ASSEMBLY ........................ MI02009-3
1. TRANSMISSION SERVICING POINTS ........................ MI02010-3
1.AXI.FAND WI'_J::J.END ASSEMBLY SERVICING POINTS ....... MI02011-3
1. PARKING BRAKE LINKAGE ............................... MI03006-3
1. BRAKEFLUID RESERVOIR ............................... MI03007-2
1. SERVICE BRAKE ASSEMBLY .............................. MI03008-5
1. FUEL/WATER SEPARATOR (STANDARD) .................... MI04006-2
1. FUEL/WATER SEPARATOR (OPTION) ....................... MI04007-2
1. FUELWATER SEPARATOR ............................... MI04008-3
1. FUEL FILTER/WATER SEPARATOR (OPTION) ................. MI04009-2
1. FUEL SYSTEM ......................................... MI04010-2
1. ENGINEOIL SYSTEM.................................... MI06003-3
1. ENGINE AIR FILTER RESTRICI'ION INDICATOR ............... MI08004-2
1. ENGINEAIR INTAKESYSTEM AND FILTER .................. MI08005-2
1. BA'HP._Y _[.F.CI'KOLYTE LEVEL .......................... MI09012-2
1. HYDRAULIC FILTER ASSEMBLY ........................... MI12001-2
1. FLUID LEVEL ANDFI"IJ. LOCATIONS ....................... MI99003-3
2. DIE_EL FUEL TEMPERATURE SCALF. ....................... MI99003-5
1. ALTERNATOR/WATERPUMP DRIVE BELTS ADJUSTMENT ...... MI99004-2
CHAPTER3OVERHAUL
3.1 TRANSMISSIONLIPTING BRACKET ............................ 3-2-1
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STEWART & STEVENSON SERVICES, INC.FRONT MATIER
AIRCRAFT GROUND SUPPORT EQUIPMENT
LIST OF FIGURES (CONT.)
CHAPTER/
FIGURE TITLE PAGE
CHAPTER 4 PARTS
i.I TOW TRACTOR OVERALL VIEW ............................... 444
1.2 OPERATOR'S COMPARTMENT ......................... .....,,.. 4 4 8
1.3 CAB MODEL 416 (OPTION) ................................... 4 4 12
1.4 CAB MODEL 846 (OPTION) .............................. ..... 4-4-14
1.5 CAB MODEL 812 (OPTION) ................................... 4 4 16
2.1 ENGINE AND TRANSMISSION ASSEMBLY ...................... 4 4 20
2.2 ENGINE AND TRANSMISSION CONNECTION .................... 4 4 22
2.3 DRIVE LINE ASSEMBLY .................................... 4 4 24
2.4 STI6.'F.RABLE AXLE HOUSING ................................. 4 4 26
2.5S'I'_I_,ABLE AXLE Dtt,-t-_<ENTIAL ............................ 44 28
2.6 STIZ.F._LE AXLE S'I'I:9,RING PARTS .......................... 4 4 30
2.7 S_._'RABLE AXI.,E PLAN/_qARY HUB REDUCERS ................. 4 4 32
2.8 RIG/D _-F.HOUSING ...................................... 4 4 34
2.9 RIGID AX].I:.DI.t.I__,RENTIAL ................................. 4 4 36
2.10 RIGID _ .1::.PLANETARY HUB REDUCERS ...................... 44 38
3.1 BRAKE LINKAGE AND MASTER CYLINDER/HYDRAULIC BOOSTER . . 4 4 42
3.2 BRAKE HYDRAULIC BOOSTER ASSEMBLY ..................... 4 4 44
3.3 BRAKE SYSTEM HYDRAULIC BOOSTER CIRCUIT ................ 4 4 46
3.4 HYDRAULIC BRAKE SYSTEM ................................ 4 n. 48
3.5 FRONT BRAKE ASSEMBLY .................................. 4.4 50
3.6 REAR BRAKEASSEMBLY ................................... 44 52
3.7 PARKING BRAKE LINKAGE .................................. 4 4 54
3.8 PARKING BRAKEASSEMBLY ................................ 4456
4.1 FUELSYSTEM V¢ITH FUEL FILTER/WATER SEPARATOR (OPTION) ... 4 4.60
4.3 TI-IROITLE CONTROL ...................................... 4.4 64
6.1 TRANSMISSION LUBE OIL SYSTEM ........................... 4 4 70
6.2 ENGINELUBE OILSYSTEM.................................. d 4 72
7.1 ENGINECOOLINGSYSTEM .................................. 4 4 76
8.1 AIR INLETASSEMBLY...................................... 4--4-80
8.2 EXHAUST SYSTEM ......................................... 4 4 82
9.1 OPERATOR CONTROL PANEL ASSEMBLY ...................... 4 4 86
9.2 I=.I.I=.CTRICALPARTS ........................................ 4 ,190
12.1STEERING COLUMN ....................................... 4 4 100
CD274 xii
El1287 REV3

STEWART & STEVENSONSERVICES, INC. FRONT MAv.t.e,R
AIRCRAFtGROUND SUPPORT EQUIPMENT
LIST OF FIGURES (CONT.)
CHAPTER/
FIGURE TITLE PAGE
12.2 HYDRAULIC STI:_RING VALVE ASSEMBLY .................... 4 4 102
12.3 HYDRAULIC FILTER ASSEMBLY............................. 4 4 104
12.4 HYDRAULIC STF.F.RING PUMP............................... 4,1 106
12.5 HYDRAULIC STI_.ERING SYSTEM ............................. 4 4 108
CD274 xiii
El1287REV 3

STEWART &STEVENSON SERVICES, INC. FRONT MATI_R
AIRCRAFt GROUND SUPPORT EQUIPMENT
LISTOF TABLES
CHAPTER/
TABLE NO. TITLE PAGE
CHAPTER 1 GENERAL INFORMATIONAND OPERATING INSTRUCTIONS
2.1 NORMAL OPERATING CONDITIONS ............................ 1-2--4
2.2 CONTROLS AND INDICATORS ......................... , ....... 1-2-7
3.1 SPECIFICATIONS ........................................... 1-3-1
3.2 ENGINE LUBE OIL VISCOSITY SELECI'ION ....................... 1-3-5
3.3 SERVICING POINTS ......................................... 1-3-7
CHAPTER 2 MAINTENANCE
1.1PREVENTIVE MAINTENANCE SCHEDULE ........................ 2-1-2
2.1NO RESPONSE WHEN ENGINE START SWITCH IS ENERG'r77_D....... 2-2-3
2.2 ENGINE CRANKS BUT WlI3.NOT START ........................ 2-2-4
2.3 HYDRAULIC STI_._G TROUBLESHOOTING ..................... 2-2-5
2.4HYDRAULIC BRAKE TROUBLESHOOTING ....................... 2-2-7
2.5 INDICATOR LAMP AND LIGHT TROUBLESHOOTING ............... 2-2-8
2.6 GAUGE TROUBLESHOOTING .................................. 2-2-9
3.ILIST OF P-,vi_t.;llVE MAINTENANCE INSTRUCTIONS............... 2-3-3
1. ENGINE LUBEOIL VISCOSITYSI:J.I:::CHON CHART............ MI06003-4
1. ENGINE LUBE OIL SPECIPICATIONS ........................ MI99003-6
CHAPTER 4 PARTS
1.1 PARTS LIST (EXAMPLE) ...................................... 4.-1-1
3.1 ALPHA-NUMER.ICINDEX ..................................... 4-3-3
CD274xiv
El1287REV 3

STEWART & STEVENSON SERVICES, INC. FRONT MATI_R
AIRCRAFT GROUND SUPPORT EQUIPMENT
INTRODUCTION
This manualcontains instructions for the overhm_l,maintenance, and operationof the:
MODEL GT-50DZ TOW TRACTOR
Full benefitof the long life and dependability built into these units can be realized through proper
operation and maintenance. Of equal importance is theuse of proper tools and procedures during
equipment overhaul.
Personnelresponsible for operation and maintenance should studythe sections of the manualpertaining
totheirparticular dudes. Similarly, before beginning a repair or overhaul job, the service technician
should read the manual careftdlyto become familiar with the components, parts, or subassemblies of the
equipment.
UNIT IDENTIFICATION
To aid the technician in repair or service work on this mail a Stewart & Stevenson identification
nameplate is located on the operator's compartmem of the unit_
o
STEWART & STEVENSON
AIRCRAFT GROUND EQUIPMENT
S,ER_L | ---'_:
NUMBER1
I --- |
WORK --] DATE t --1
ORDER !; OF :
NUMBER; __ I MFR [ .-- |
STEWART& ST'_/ENSON SERV. PH 713-923-2161
P.O.BOX 1(;37 _,T_t_Y.: 762<J01
HOUSTON. TEXAS _CABLE: ST_STEVE
7TO01_HOE.
o o
A73-_0/06
The serial nmnber identificationof each unit will appear on the nameplate (as shown above) along with
the work order and date of manufacture. The mailing address ofStewart & Stevenson, telephone number,
telex number, and cable information are all located on the bottom of the nameplate. This necessary
information will ensure the customer a fast andaccurate response to anyparts and/or service request.
Please verify the serial number on the unit's identification nameplate and ENTER YOUR UNIT SERIAL
NUMBER HERE:
If applicable, enter your company identification number here:
CD274 xv
El1287REV 3

STEWART & STEVENSON SERVICES, INC. FRONT MATIV._R
AIRCRAFT GROUND SUPPORT EQUIPMENT
TECHNICAL ASSISTANCE
Forparts or warranty assistance,wire,write, or call:
Stewart & StevensonServices, Inc.
P.O. Box 1637
Houston, Texas 77251-1637.
For Airline Pans: 800-231-8181
(Texas Residents: 713-923-2161; ask for Airline Parts Department.)
For Airline Service: 800-527-3246; Stewart & Stevenson Warranty Department
(Texas Residents: 713-923-2161; ask for Warranty Department.)
Be sure to list lhe equipment model number, rating, specific nature of llaeproblem, and abe suspected area
ofmalfunction.
CD274 xvi
El1287 REV3

STEWART & STEVENSON SERVICES, INC.FRONT MATTER
AIRCRAFT GROUND SUPPORT EQUIPMENT
SAFETY PRECAUTIONS
The safety precautions contained herein should be observed during all phases of operation.
1. Check to ensure that the parking (emergency) brake is set whenever the unit is intended to remain
stationary.
2. Clean or service the unit only when the engine is shut down.
3. When cleaning, use only an approved solvent to prevent damage and/or deterioration to the
equipment.
4. When filling the fuel tank, do not smoke or use an open flame in the vicinity.
5. Prior to starting the unit, ensure that no loose bars, tools, parts, and the like are lying in or on a
part of the unit, as they could cause serious damage to the unit or bodily injury to personnel.
6. Ensure that personnel are well clear of the tractor wheels before beginning this procedure. Death
or serious injurycan result if someone iscrushed between the wheels and the tractor.
7. When operating inan enclosed area, pipe the exhaust fumes outside.
8. Follow the manufacturer's recomlr_ndations to properly maintain equipment.
9. In ease of malfunction, resulting ina shutdown, do not attempt to re-start the engine until the
trouble has been corrected. Failure to comply could result in serious damage to the equipment.
I0. In case of accident, shut down the unit immediately.
11. The tow tractor must be safely supported on blocks or other appropriate supporting devices before
personnelmayattempt accessunderneath thetractor. Equipment used to raise andsupport the tow
tractor must be rated to withstand 150% (1-1/2times) the tractor'sgross vehicleweight.
12. Thisequipment usesboth metric and S.A.E. (inch-type) nuts, bolts, and screws which can present
special service requirements. Many metric measurements are very close in dimension to S.A.E.-rnted
nuts, belts, and screws. The use of hardware with mismatched threads or improperly sized components
can result in damage, malfunction, or possible personal injury. Components and hardware removed
from tow tractor should be saved for re-use when possible. If not re-useable, care should be takento
select a replacement that matches the original in dimension, strength, andpitch ofthreads.
CD274 xvii
E11287REV 5

STEWART & STEVENSON SERVICES, INC. FRONT MAITPAR
AIRCRAFT GROUNDSUPPORT ]EQUIPM]ENT
HOW TOUSE THISMANUAL
1.Thismanual is divided intosix Chapters, witheach Chapter subdivided into applicable sections.
See the Table ofContents at the frontof each Chapterfor details ofthe contents of that respective
Chapter.
2. The page numbering system utilizes a three-part munber. The explanation is as follows:
Section Number\ /Sequential page number
_t ./within the Section
Chapter Number _ 2-3.4_
ORIG_'_"'Date of revision of this
page or ORIG for the
original issue.
3. Cautions,
Warnings, and Notes are used throughout this manual. The forms and explanations are as follows:
WARNING
REFERS TO POTENTIALDANGER TO PERSONNEL IN
TIIE FOLLOWING PARAGRAPH.
CAUTION
REFERS TO POTENTIAL DAMAGE TO EQUIPMENT OR
COMPONENTS IN THEFOLLOWING PARAGRAPH.
NOTE
Calls anantion to methods which make the job easier, or to
operating procedures, conditions, etc., which shouldbe
highlighted. Notes appear before or after related text, whichever
ismore logical.
4.Chapter6,Optionsand Manufactnrer'sData,isdividedintosections,when applicable.Minor
optionsareincludedinthefirstfivechaptersofthismanual.MajoroptionswillbedocumentedinChapter
6.RefertotheTableofContentsChapter6 formajoroptions.Anyinformationon adjusUncnts,opcration,
ormaintenancecontainedinChapter6 willsupersedeany relatedinformationinthefirstfivechaptersof
thismamaal.Additionalornew drawingsand schematics,as requiredformajoroptions,willalsobe
located in Ompter 6 in sections in which theyapply, litis recommended you review the TableofContents
in CAmpter 6 and check your unit to see if it is equipped with any of the options listed.
CD274 xviii
El1287 REV 3

STEWART & STEVENSON SERVICES, INC. CHAPI_R 1
AIRCRAFTGROUND SUPPORT EQUIPMENT
CHAPTER 1
OPERATIONS
TABLE OF CONTENTS
SECTION/
PARAGRAPH DESCRIPTION PAGE
1GENERAL DESCRIPTION....................................... 1-1-1
1.1 INTRODUCTION................................................ 1-1-1
1.2 UNIT DESCRItrI'ION ............................................. 1-t-1
1.3 ENGINE...................................................... 1-1-3
1.4 TRANSMISSION ................................................ 1-1-3
1.5 DRIVE LINE ASSEMBLY ......................................... 1-1-3
1.6 FUELSYSTEM................................................. 1-1-3
1.7 AIR INTAKE SYSTEM ........................................... 1-1-4
1.8 EXHAUST SYSTEM ............................................. 1-1-4
1.9 LUBRICATIONSYSTEM .......................................... 1-1-4
1.10 COOLINGSYSTEM.............................................. 1-1-4
1.11 STEERING SYSTEM ............................................. 1-1-4
1.12 BRAKE SYSTEM ................................................ 1-I-6
1.12.5 Parking Brake ................................................... 1-1-9
1.13 LIPT CAB(OPTIONAL) ........................................... 1-1-9
1.14 ELECTRICAL SYSTEM. .......................................... 1-1-9
1.14.2 Engine Starting and Battery Charging Circuits ............................ 1-1-10
1.14.3 Brake Booster Motor Circuit ........................................ 1-1-10
1.14.4 EngineRun Relay Circuit. ......................................... 1-1-10
1.14.5 Horn Circuit. ................................................... 1-1-10
1.14.6 Engine Instrument Circuit .......................................... 1-1-10
1.14.7 LightCircuit.................................................... 1-1-10
1.14.8 Warning Light Circuit. ............................................ 1-I-11
1.14.9 AuxiliaryLight Circuit............................................ 1-1-11
1.14.10 Engine Coolant Heater (Optional) ..................................... 1-1-12
1.14. I I Engine Fuel/Water Separator andFuel Heater (Optional) ..................... 1-1-12
1.14.12 Cab Circuits(Optional)............................................ 1-I-12
2 OPERATION .................................................. 1-2-1
2.1 PRE-OPERATIONAL CHECKS ...................................... 1-2-1
2.2 OPERATING PROCEDURES ....................................... I-2-3
2.3 SHUTDOWN PROCEDURE ........................................ 1-2-4
2.4 CONTROLS AND INDICATORS .................................... 1-2-6
3 SPECIFICATIONS.............................................. 1-3-1
3.1 INTRODUCTION............................................... 1-3-1
3.2 SPECIFICATION TABLES ........................................ 1-3-1
3.3 POINTS OF SERVICE, SPECIFICATION, AND CAPACITIES ............... 1-3-4
CD274 1-TOC-i
E11287 REV4