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CD444-38M 2 - 1 - 1July 2019 (Rev A)
Chapter 2 Tow Tractor Model MA-38Section 1 Maintenance Manual
Chapter2:PreventiveMaintenanceSection 1: Introduction - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - -2-1-1
1.1 Safety Precaution - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - -2-1-11.2 Preparation for Use - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - -2-1-1
1.2.1 Pre-Operation Checks - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - -2-1-1Section 2: Preventive Maintenance - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - -2-2-1
2.1 Periodic Maintenance/Service Schedules and Checklist - - - - - - - - - - - - - - - - - -2-2-12.1.1 Daily or Every 10 hours Maintenance Checks- - - - - - - - - - - - - - - - - - - - - - -2-2-22.1.2 Weekly or Every 50 hours Maintenance Checks - - - - - - - - - - - - - - - - - - - - -2-2-32.1.3 Bi-Weekly or Every 100 Hours Maintenance Checks- - - - - - - - - - - - - - - - - -2-2-32.1.4 Monthly or Every 200 Hours Maintenance Checks - - - - - - - - - - - - - - - - - - -2-2-42.1.5 Two (2) Months or Every 500 Hours Maintenance Checks- - - - - - - - - - - - - -2-2-42.1.6 Six (6) Months or Every 1000 Hours Maintenance Checks- - - - - - - - - - - - - -2-2-52.1.7 Yearly or 2000 Hours Maintenance Checks - - - - - - - - - - - - - - - - - - - - - - - -2-2-52.1.8 Every 2 Years or 4000 Hours Maintenance Checks - - - - - - - - - - - - - - - - - -2-2-6
Section 3: Maintenance Procedures - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - -2-3-1
3.1 Safety Precautions - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - -2-3-13.2 Jacking Instructions - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - -2-3-1
3.2.1 Free Standing Jack - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - -2-3-13.2.2 Fluid Level Checks - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - -2-3-23.2.3 Engine Oil Level - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - -2-3-23.2.4 Engine Coolant Level - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - -2-3-33.2.5 Transmission Oil Level - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - -2-3-43.2.6 Drive Axle Gear Box Oil - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - -2-3-53.2.7 Brake Fluid Level- - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - -2-3-63.2.8 Fuel Level - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - -2-3-63.2.9 Windshield Fluid - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - -2-3-6
3.3 Service and Lubrication Points - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - -2-3-83.4 Adjustments - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - -2-3-9
3.4.1 Fan Belt Adjustment- - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - -2-3-93.4.2 Service Brake Adjustment - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - -2-3-103.4.3 Park Brake Adjustments - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - -2-3-103.4.4 Steering Gear Box Adjustment - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - -2-3-113.4.5 Toe-In Adjustment - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - -2-3-113.4.6 Cab Door Adjustment- - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - -2-3-113.4.7 Vertical Headlight Adjustment - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - -2-3-123.4.8 Horizontal Headlight Adjustment - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - -2-3-123.4.9 Shifter Adjustment - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - -2-3-12
3.5 Service Procedures - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - -2-3-123.5.1 Engine Oil and Filter Change - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - -2-3-123.5.2 Engine Air Filter Replacement- - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - -2-3-133.5.3 Transmission Oil and Filter Change- - - - - - - - - - - - - - - - - - - - - - - - - - - - -2-3-143.5.4 Axle Gear Box - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - -2-3-153.5.5 Brake Assembly: Wheel Cylinder Bleed - - - - - - - - - - - - - - - - - - - - - - - - - -2-3-163.5.6 Fuel Filter Change - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - -2-3-16
Section 4: Troubleshooting - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - -2-4-1
4.1 Engine and Transmission- - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - -2-4-14.2 Alternator - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - -2-4-4
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2- 1 - 2 CD444-38MJuly 2019 (Rev A)
‘ Tow Tractor Model MA-38 Chapter 2Maintenance Manual Section 1
4.3 Rear Axle - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - -2-4-54.4 Steering - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - -2-4-54.5 Brake System - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - -2-4-64.6 Electrical System- - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - -2-4-7
4.6.1 Battery - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - -2-4-74.6.2 Lights (12 Volt System) - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - -2-4-74.6.3 Wiper Motor - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - -2-4-84.6.4 Horn - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - -2-4-9
Section 5: System Schematics - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - -2-5-1
5.1 Electrical Schematics- - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - -2-5-35.2 Hydraulic Schematics - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - -2-5-9
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CD444-38M 2 - 1 - 1July 2019 (Rev A)
Chapter 2 Tow Tractor Model MA-38Section 1 Maintenance Manual
Section1:Introduction
Preventive maintenance is regularly performed maintenance that will lessen the likelihood of equipmentfailure. Preventive maintenance is performed while the equipment is still operating properly, so that it doesnot break down unexpectedly. The following sections provide information on how to maintain the vehicle toensure optimal equipment performance.
1.1SafetyPrecaution
Read the Safety chapter at the beginning of this manual and refer to the Warnings, Cautions, and notesthroughout this manual before proceeding with any Maintenance.
1.2PreparationforUse
Set the parking brake by pulling the park brake lever and perform Pre-Operation Checks prior to puttingthe unit into service.
1.2.1Pre-OperationChecks
The following items must be checked before putting the unit into service.
1.2.1.1EngineandTransmission
1. Check engine for oil level and contamination, add oil if needed see Section 2: "Layouts" for lubri-cation specification.
2. Check for water leaks.
3. Check radiator coolant level. If coolant is needed, make sure radiator drain valve is closed, thenadd required coolant.
4. Check transmission fluid level.
5. Check transmission cooling lines for proper connection.
6. Check for dust in air cleaner dust cup.
7. Check for damaged parts and loosened bolts and nuts.
8. Start engine and check for proper functions of meters and pilot lamps with no stains.
CAUTION:Every operator and mechanic/technician involved with this equipment must read andabide by the Safety sections.
WARNING:
STOP THE ENGINE AT A FLAT AND WIDE SPACE WHEN CHECKING.
KEEP DUST OR FUEL AWAY FROM THE BATTERY, WIRING, MUFFLER ANDENGINE TO PREVENT A FIRE. CHECK AND CLEAR THEM BEFORE OPERATINGEVERYDAY. PAY ATTENTION TO THE HEAT OF THE EXHAUST PIPE OR EXHAUSTGAS SO THAT IT CAN NOT IGNITE TRASH.
BE SURE TO INSTALL SHIELDS AND SAFEGUARDS ATTACHED TO THE ENGINEWHEN OPERATING.
NOTE:This check is to determine if there is fluid in the transmission. If any fluid shows on the dipstick,do not add transmission fluid until it is checked with the engine running, after the engine hasreached normal operating temperature
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Tow Tractor Model MA-38 Chapter 2 Maintenance Manual Section 1
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9. Check for unusual engine noise.
10. Check engine start-up condition.
11. Check slow-down and acceleration behavior.
1.2.1.2FuelSystem
1. Check all fuel line connections to make sure they are properly connected.
2. Ensure the in-line fuel shut-off valve under the tank is open.
3. Make certain fuel tank drain valve is closed.
4. Fill fuel tank with correct fuel. Refer to the engine manual included in Chapter 5 (1.1 "Vendor Infor-mation") to determine the correct fuel specifications.
1.2.1.3Axles
1. Check oil level in the rear axle and gear reduction box.
2. Add oil, if needed.
1.2.1.4Brakes
1. Check master cylinder fluid level.
2. If low, check for leaks in brake lines.
3. Check service brake to make sure it is working properly.
4. Check park brake to make sure it is working and adjusted properly.
1.2.1.5TireInflation
1. Check air pressure in tires.
2. Add air, if needed.
• Front: 60 psi (413.7 kPa)
• Rear: 65 psi (448.1 kPa)
1.2.1.6VehicleDrive
Check that the tractor drives properly in both forward and reverse directions.
1.2.1.7Battery
Connect the battery cables, if disconnected.
NOTE:When ambient temperature is low, operate the machine after the engine has been completelywarmed up.
NOTE:The rear axle and reduction gear box are internally connected See Section 2: "Layouts" forLubrication Specification.
CAUTION:
THE RECOMMENDED TIRE PRESSURES LISTED ARE FOR THE 8.00 X 16.5 (DRIVEWHEELS) AND 6.9 X 9.0 (STEER WHEELS) TIRES THAT ARE STANDARD ON THE MAUNIT. OTHER OPTIONAL TIRES SHOULD BE INFLATED ACCORDING TO THE TIREMANUFACTURER SPECIFICATIONS.
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CD444-38M 2 - 2 - 1July 2019 (Rev A)
Chapter 2 Tow Tractor Model MA-38Section 2 Maintenance Manual
Section2:PreventiveMaintenance
2.1PeriodicMaintenance/ServiceSchedulesandChecklist
Routine maintenance is essential if the vehicle is to be an efficient materials handling unit. Lack of mainte-nance will result in costly repairs and interruptions in daily operations.
The unit should be maintained in accordance with periodic schedules. Maintain the unit by performing theperiodic maintenance procedures as listed in this chapter.
During the periodic maintenance of the unit, follow the instructions for service/adjustment of the compo-nents and systems as described in this chapter, the manufacturers’ service instructions and manuals.
Perform maintenance at whichever interval occurs first. At each scheduled maintenance interval, performall previous maintenance checks that are due for scheduled maintenance. The required maintenanceschedules are as follows:
• Daily or every 10 hours of operation
• Weekly or every 50 hours of operation
• Every 100 hours of operation
• Monthly or every 200 hours of operation
• Every two months or 500 hours of operation
• Every six months or every 1000 hours of operation
• Annually or 2000 hours of operation
• Two years or 4000 hours of operation
CAUTION:Only qualified personnel should service this tractor. Do not attempt to carry out repairsunless you are a qualified maintenance mechanic. Report a faulty tractor and do notuse until repaired.
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Tow Tractor Model MA-38 Chapter 2 Maintenance Manual Section 2
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2.1.1DailyorEvery10hoursMaintenanceChecks
Table2-2-1:DailyorEvery8hoursMaintenanceChecksandServiceProcedures
No. Item DailyCheck/8HourChecks
Over filling engine crankcase can result in oil leaks or bearing damage. Check the oil level fre-quently while adding oil to avoid over filling.
THE COOLING SYSTEM IS PRESSURIZED. ESCAPING STEAM AND HOT COOLANT CANCAUSE SEVERE BURNS. NEVER OPEN A RADIATOR CAP WHEN COOLANT TEMPERATUREEXCEEDS 200 °F (95 °C). USE A CLOTH OR WEAR SUITABLE GLOVES TO HANDLE A HOTRADIATOR PRESSURE CAP. ETHYLENE GLYCOL ANTIFREEZE IS TOXIC AND IRRITATES THESKIN. WASH ANY PART OF THE BODY THAT COMES IN CONTACT WITH ANTIFREEZE SOLU-TION AS SOON AS POSSIBLE.
1
Engine System
Check oil level and top oil up if necessary.
2 Check coolant level and top up if necessary
3 Check engine tightness (visual inspection for leaks).
4 Check and clean air filter element if necessary.
5 Check Fan Belt.
6 Fuel System Check fuel level.
DO NOT CHANGE PNEUMATIC TIRE FOR CUSHION TIRE OR VICE VERSA WITHOUT FIRSTCONSULTING TUG. TIRES OF A DIFFERENT TYPE OR MAKE, TREAD OR MATERIAL CANREDUCE THE LOAD CAPACITY OR AFFECT SAFETY.
7Tires
Check the pressure of the pneumatic tires.
8 Check the tire treads for damage. Remove any stone, etc.
9 ControlsCheck that all controls are in good working order. Report a faulty control and do not use until repaired.
10
Lights
Check the operation and aiming of the headlights.
11 Check the operation of backup, tail, stop and turn signal lights (if equipped).
12Check the operation of the cab marker lights, the heater, the wiper and cab light, if equipped.
13 Horn Sound the horn.
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CD444-38M 2 - 2 - 3July 2019 (Rev A)
Chapter 2 Tow Tractor Model MA-38Section 2 Maintenance Manual
2.1.2WeeklyorEvery50hoursMaintenanceChecks
2.1.3Bi-WeeklyorEvery100HoursMaintenanceChecks
Table2-2-3:Bi-WeeklyorEvery100HoursMaintenanceChecks
Table2-2-2:WeeklyorEvery50hoursMaintenanceChecks
No. Item Weekly/50HourChecks
LUG NUTS MUST BE RETIGHTENED TO 125 FT-LB (169.5 NM) AFTER ANY CHANGE OF A WHEEL AND ANYTIME THE LUG NUTS HAVE BEEN LOOSENED FOR ANY REASON, AND AT THE INTERVALS SPECIFIED IN THIS PERIODIC MAINTENANCE SECTION.
1
Engine System
Change engine oil.
2 Check underneath for oil leaks and damage.
3 Replace the oil filter cartridge.
4Open the evacuator valve once a week under ordinary conditions - or daily when used in a dusty place.
NOTE: Only the initial change is required at 50-hours, check monthly or every 200 hours thereafter.
5 TransmissionCheck the transmission fluid level (with engine running at normal operating tem-perature).
6
Axles
Check the drive axle U-bolts and tighten if required.
7 Check drive axle and reduction gear box oil level
8 Check king pins for looseness.
9 Nuts and Bolts
Check that the wheel lug nuts are tightened to 125 ft-lb (169.5 Nm).
10 Check nuts and bolts for tightness. If required, torque to specified torque.
TRANSMISSION FLUID MAY REACH HIGH TEMPERATURES AND THE CASE MAY BE UNDER PRESSURE. CARE MUST BE TAKEN WHEN REMOVING THE DIPSTICK TO AVOID BURNS.
11Brake
SystemCheck the level of the brake fluid in the master cylinder. If low, top off as neces-sary.
12 Steering System
Check hydraulic fluid level.
13 Check steer pins for looseness
14 Fuel System Check fuel hoses for signs of wear or damage.
No. Item Bi-Weekly/100HourChecks
1EngineSystem
Adjust engine fan belt if necessary.
2 Clean and Adjust Spark Plugs if necessary.
3 Clean air filter element.
4Fuel
System Check and Change Fuel Filter if necessary.
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2 - 2 - 4 CD444-38MJuly 2019 (Rev A)
Tow Tractor Model MA-38 Chapter 2 Maintenance Manual Section 2
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2.1.4MonthlyorEvery200HoursMaintenanceChecks
2.1.5Two(2)MonthsorEvery500HoursMaintenanceChecks
Table2-2-4:MonthlyorEvery200HoursMaintenanceChecks
No. Item Monthly/200HourChecks
1
Engine System
Change engine oil
2 Change oil filter cartridge.
3 Check the fan and alternator belts; tighten, if necessary.
4 Inspect radiator hoses and clean radiator exterior.
5
Brake System
Check park brake operation. With the park brake handle in ‘lock’ position, the trac-tor should not move on an 8% or less grade. If the tractor does not move, no adjustment is necessary, but if the tractor rolls, then adjustment is advised. Fol-low the recommended adjustment instructions in this section.
6 Check service brake operation.
7Inspect brake pads; replace if pads are less than one-eighth (1/8) of an inch (3.175 mm).
8 Lube the service brake pedal pivot.
9 Lube the parking brake lever pivots.
NOTE:The initial change is required at the 50-hour maintenance level, change monthly or every 200hours thereafter.
10Axles
Change drive axle and reduction gear box oil.
11 Lube the drive shaft joints.
12 Operator Compartment/
Cab
Lube the adjusting slides beneath the operator’s seat.
13 Lube the throttle linkage.
14 Lube the cab door handles (if equipped).
15Steering System
Check power steering fluid level (when applicable).
16 Hood Lube the hood latches and hinges.
17 Fittings Lube all grease fittings.
Table2-2-5:Two(2)MonthsorEvery500HoursMaintenanceChecks
No. Item TwoMonths/500HourChecks
1Engine System
Change engine fan belt.
2 Axles Check ball joints and tie rod ends looseness.
3 Wheels Inspect front wheel bearings; clean and repack.
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CD444-38M 2 - 2 - 5July 2019 (Rev A)
Chapter 2 Tow Tractor Model MA-38Section 2 Maintenance Manual
2.1.6Six(6)MonthsorEvery1000HoursMaintenanceChecks
2.1.7Yearlyor2000HoursMaintenanceChecks
Table2-2-6:Six(6)MonthsorEvery1000HoursMaintenanceChecks
No. Item Six(6)Months/1000hourChecks
1 Engine System
Check PCV valve
2 Adjust valve clearance
3Transmis-
sionChange transmission fluid and filter.
4Axles
Check the differential and reduction gear box bolts are tightened to 41 ft-lb (55.6 Nm).
5 Change drive axle and reduction gear box oil.
NOTE: The initial change is required at the 200-hour maintenance level, change every six (6) months or 1200 hours thereafter.
6Hydraulic System
Change hydraulic fluid and clear magnetic drain plug of debris.
7Brake
SystemCheck cylinder compression.
8Electrical System
Check battery and cable connectors.
9Hoses and Fastenings
Check fastenings, hose unions/clips (renew if damaged).
Table2-2-7:Yearlyor2000HoursMaintenanceChecks
No. Item Yearly/2000HoursChecks
1Engine System
Replace the Air Cleaner element every year or every 6 cleanings. Also replace if the primary element is stained heavily.
2ElectricalSystem
Change spark plugs.
3Air Intake System
Check intake pipe and clamp bands.
4
Fuel System
Change fuel filter.
5 Clean fuel tank.
6 Change fuel pipe clamps.Prop
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Tow Tractor Model MA-38 Chapter 2 Maintenance Manual Section 2
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2.1.8Every2Yearsor4000HoursMaintenanceChecks
Table2-2-8:Every2Yearsor4000HoursMaintenanceChecks
Item 2Years/4000HoursChecks
1 Engine SystemReplace hoses and hose clamps, if checked and found that hoses are swollen, hardened or cracked.
2 Cooling System
Change engine coolant.
3 Change radiator hoses and band clamps.
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CD444-38M 2 - 2 - 7July 2019 (Rev A)
Chapter 2 Tow Tractor Model MA-38Section 2 Maintenance Manual
Serial Number:Manufacture Date:
Service Requirement in Hours Daily 50 100 200Check/ensure all controls are in good working order
Check fuel level
Check Lubricating oil level (If necessary top up)
Check engine coolant level
Check engine coolant system for leaks and cleanliness
Check the pressure of the pneumatic tires
Check tire treads, remove any foreign objects
Check the operation and aiming of the headlights
Check the operation of backup, tail, stop and turn signal lights (if equipped)
Check operation of Cab marker lights, heater/air, front & rear wipers, defroster, fan, some light(s) & alarms/mircro switches (lift cab only)Sound the horn
Check exhaust system including exhaust after treatment components for leaks.Check coolant, oil, fuel, and vacuum hoses/pipes for leaks, damage, deterioration and correct routing.Check Fan Belt
Check underneath for oil leaks and damage
Check that the wheel lug nuts are tightened to 125 ft-lb (169.5 Nm)
Check nuts and bolts for tightness. If required, torque to specified torque.
Change engine oil.
Check battery charge
Check the drive axle U-bolts and tighten if required
Check drive axle and reduction gear box oil level
Check the transmission fluid level (with engine running at normal operating temperature)Check the level of the brake fluid in the master cylinder. If low, top off as necessaryCheck hydraulic fluid level
Check fuel hoses for sign of wear or damage
Check king pins and steer pin for looseness
Check all visible electrical wiring for security, correct routing and evidence of chafing or heat damageChange Oil Filter Cartridge
Check/Change Fuel Filter
Clean Air filter Element
Adjust Fan belt (if necessary)
Clean/Adjust Spark Plug (if necessary)
Check park brake operation.
Check service brake operation
Inspect brake pads; replace if pads are less than one-eighth (1/8) of an inch (3.175 mm)Lube the service brake pedal pivot
Lube the parking brake lever pivots
Check the alternator belts; tighten, if necessary
Inspect radiator hoses and clean radiator exterior.
Lube the drive shaft joints
Lube the adjusting slides beneath the operator’s seat
Lube all grease fittings
Lube the hood latches and hinges
Lube the cab door handles (if equipped)
TUG Model MA-38 (Kubota Gas Engine) Tow Tractor
ID Number:Date:
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2 - 2 - 8 CD444-38MJuly 2019 (Rev A)
Tow Tractor Model MA-38 Chapter 2 Maintenance Manual Section 2
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Notes
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CD444-38M 2 - 2 - 9July 2019 (Rev A)
Chapter 2 Tow Tractor Model MA-38Section 2 Maintenance Manual
* Change more often when operating under dusty conditions.
Serial Number:Date:
Service Requirement in Hours 500 1000 2000 4000Change fuel cartridge for filter
Check intake air pipes for damage
Inspect front wheel bearings; clean and repack
Check ball joints and tie rod ends looseness
Change Fan Belt
Replace lubricating oil.
Check the differential and reduction gear box bolts are tightened to 492 in-lb (55.6 Nm).Check PCV Valve
Adjust Valve Clearance
Change drive axle and reduction gear box oilCheck cylinder compression
Check battery and cable connectors
Check engine mounting (tighten, replace if damaged when necessary).
Check fastenings, hose unions/clips (renew if damaged)
Change Fuel pipe and clamps
Clean Fuel Tank
Replace dry air filter.
Change hydraulic fluid and clear magnetic drain plug of debris.
Change transmission fluid and filter.
Clean Radiator and water jacket
Change Spark Plug
Replace fuel pre-filter.
Change radiator hoses and clamp bands
Change Air Cleaner Element*
Check intake pipe and clamp bands
Change intake pipe and clamp bands
Change rubber piping related oil seperator
Replace Coolant
Change radiator hoses and band clamps
Change breather tube
Date:ID Number:
TUG Model MA-38 (Kubota Gas Engine) Tow Tractor
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2 - 2 - 10 CD444-38MJuly 2019 (Rev A)
Tow Tractor Model MA-38 Chapter 2 Maintenance Manual Section 2
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Notes
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CD444-38M 2 - 3 - 1July 2019 (Rev A)
Chapter 2 Tow Tractor Model MA-38Section 3 Maintenance Manual
Section3:MaintenanceProcedures
The following procedures outline the steps and precautions to take when servicing the unit for mainte-nance or repair.
3.1SafetyPrecautions
Read the Safety chapter at the beginning of this manual and refer to the Warnings, Cautions and Notesthroughout this manual before proceeding with any overhaul.
3.2JackingInstructions
The unit can be supported by either free standing jack stands or the unit’s hydraulic jacks.
3.2.1FreeStandingJack
1. Park the unit on level ground.
2. Chock the wheels and apply parking brake.
3. Place a warning tag on control panel stating “Unit Out of Service.”
4. Praise the unit using equipment with lifting capacity at least one and a half (1.5) times greater thanthe unit’s weight.
5. Place the jack stands under the unit at the appropriate location(s). See Figure
6. Disconnect battery cables from starting motor and from engine ground
WARNING: ALWAYS REVIEW SAFETY PRECAUTIONS PRIOR TO PERFORMING ANYWORK ON THIS EUQIPMENT
CAUTION:Every operator and mechanic/technician involved with this equipment must read andabide by the Safety sections.
WARNING:
TO AVOID INJURY TO PERSONNEL OR DAMAGE TO EQUIPMENT, ALWAYSUSE LIFTING EQUIPMENT, SAFETY JACKS AND CHAINS WITH A SAFEMINIMUM CAPACITY OF ONE AND A HALF (1.5)TIMES THE WEIGHT OFTHE VEHICLE BEING LIFTED.
TO AVOID INJURY TO PERSONNEL, NEVER WORK UNDER UNIT WHENUNIT IS SUPPORTED ONLY BY JACKS.
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Figure2-3-1:JackingPoints
3.2.2FluidLevelChecks
Perform all fluid level checks with the unit parked on a level surface. Ensure the unit’s parking brake isapplied and wheels are chocked.
3.2.3EngineOilLevel
1. With the engine stopped and cooled, locate the engine oil dipstick. See Figure 2-3-4 Service andLubrication Points.
2. Pull up the dipstick and wipe clean.
3. Return the dipstick, withdraw it and read the oil level.
WARNING:
ALWAYS SET THE PARK BRAKE ON PRIOR TO SHUTTING OFF THE UNITOR EXITING THE VEHICLE. OTHERWISE, THE UNIT CAN ROLL AWAY,CAUSING DEATH, SEVERE PERSONAL INJURY, AND/OR PROPERTY DAM-AGE.
NOTE: Check the engine oil level before starting or more than 5 minutes after stopping the engine.
NOTE: Maintain the oil level between the grooved region.
Jacking Points
Jacking Points
Jacking Points
Jacking Points
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4. When the oil level is below the dipstick grooved region, add oil through the oil filler to the bring thelevel up to the grooved area.
5. After adding oil, wait more than 5 minutes and check the oil level again. It takes some time for theoil to drain down to the oil pan.
3.2.3.1EngineOilCondition
When moisture is found on the oil fill cap and/or the engine oil has a milky appearance an engine oil andfilter service is required.
1. Perform an engine oil and filter service.
2. After the engine oil and filter service, drive the unit at operating temperature 215ºF (101.6ºC)under load for at least 30 minutes.
3. Ensure the unit is driven at operating temperature for a minimum of 30 minutes every 50 hoursthereafter.
3.2.4EngineCoolantLevel
1. When the engine is warm, turn off the unit and wait until the coolant temperature is below120°F(50°C) before checking the coolant level.
2. With the engine stopped and cooled, locate the coolant reservoir/expansion tank.
3. Ensure coolant level is between the “Full” and “Low” markings on the radiator or reservoir/ expan-sion tank.
CAUTION:
Never operate the engine when the oil level is below the “L” (low) mark or above the“H” (high) mark. Damage to the engine or poor engine performance may occur.
Over-filling the engine crankcase can result in oil leaks or bearing damage. Check theoil level frequently while adding oil to avoid over-filling the crankcase.
NOTE:
Due to natural environmental conditions, condensation will deposit moisture inside theengine crankcase. This moisture will be vaporized when the motor oil reaches an operatingtemperature above 215ºF (101.6ºC). Operations with short driving distances may not providethe engine with enough time for the engine oil to exceed 215ºF (101.6ºC), resulting in anaccumulation of moisture in the engine oil, causing the engine oil to have a milky appear-ance. To prevent this, all engines should be brought to operating temperature, and drivenunder load, for a minimum of 30 minutes every 50 hours.
WARNING:
THE COOLING SYSTEM IS PRESSURIZED. ESCAPING STEAM ANDHOT COOLANT CAN CAUSE SEVERE BURNS. NEVER OPEN A RADIATORCAP WHEN COOLANT TEMPERATURE EXCEEDS 120°F (50°C).
USE A CLOTH OR WEAR SUITABLE GLOVES WHEN HANDLING A HOTRADIATOR PRESSURE CAP. ETHYLENE GLYCOL ANTIFREEZE IS TOXICAND WILL IRRITATE THE SKIN. WASH ANY PART OF THE BODY THATCOMES IN CONTACT WITH ANTIFREEZE SOLUTION AS SOON AS POSSI-BLE.
NOTE:Some minor coolant loss is normal due to thermal expansion. A very low coolant level indi-cates serious leakage in the system that must be located and corrected immediately.
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4. When the coolant level is below the “Low” marking, get the specified pre-mixed solution.
5. Remove the radiator cap and check to see that coolant reaches the supply port
6. Add coolant solution to restore the fluid to the proper level.
7. Re-tighten radiator cap.
8. Check all drain shutoff-valves.
3.2.4.1ChangingEngineCoolant
1. To drain coolant, always open both drain shutoff-valves and simultaneously open the radiator capas well.
2. Remove the overflow pipe of the radiator pressure cap to drain the recovery tank.
3. Use prescribed coolant 2.22 US gal (8.4L).
3.2.5TransmissionOilLevel
Check the transmission oil level daily or before operation.
1. Ensure the parking brake is set.
2. Place the transmission shift lever in the neutral (N) position.
3. Start the engine.
4. With the service brake pedal depressed, cycle the transmission through all gears and allow trans-mission to reach operating temperature.
WARNING: ETHYLENE GLYCOL ANTIFREEZE IS TOXIC AND WILL IRRITATE THE SKIN.WASH ANY PART OF THE BODY THAT COMES IN CONTACT WITH ANTI-FREEZE SOLUTION AS SOON AS POSSIBLE.
CAUTION:DO NOT add cold coolant to a hot engine. Engine castings can be damaged. Allow theengine to cool to below 120°F (50°C) before adding coolant.
NOTE: With the radiator cap kept closed, a complete drain of water is impossible.
CAUTION:An improperly tightened radiator cap or a gap between the cap and the seat quickensloss of coolant.
NOTE:
To remedy quick decrease in engine cooling capacity:
1. Check for any dust and dirt between the radiator fins and tube. If any, remove themfrom the fins and the tube.
2. Check the tightness of the fan belt. If loose, tighten it securely.
3. Check the internal blockage in the radiator hose. If scale forms in the hose, clean withthe scale inhibitor or its equivalent.
NOTE:The transmission oil level must be checked with the engine running at its normal operatingtemperature.
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5. Return the shift level to the neutral (N) position.
6. Pull the transmission oil dipstick out of its tube and wipe it clean.
7. Re- the dipstick, withdraw it and read the oil level.
8. When the oil level is down to the dipstick “ADD” mark, add oil through the oil filler to bring the levelup to “FULL”.
3.2.6DriveAxleGearBoxOil
The oil level can be checked in the rear axle and gear reduction box to add oil, if needed.
1. Park the unit on level ground and set the parking brake.
2. Chock the wheels and jack unit up.
3. Place jack stands under the unit and release parking brake.
4. Place warning tags on the control pane stating: “UNIT IS OUT OF SERVICE”.
5. Ensure that oil has cooled down before checking it.
6. Remove the plug from the oil fill port.
7. Check oil level at the filling bores.
8. If oil level is below the filling bore, fill hub assembly with clean oil until the oil level reaches the fill-ing bore.
9. After a few minutes, check the oil level again at the filling bores.
10. Keep filling with oil until the oil level remains constant.
11. Clean bore hole and oil filling plug.
12. Replace screw plug gaskets with new gaskets.
13. Screw oil filling plug back in place.
NOTE: Maintain the oil level between the “ADD” and “FULL” dipstick ranges.
CAUTION:Over-filling the transmission can result in oil leaks or possible damage. Check the oillevel frequently while adding oil to avoid over-filling the transmission.
NOTE: Refer to the transmission documentation in Chapter 5 for transmission oil recommendations/specifications.
NOTE: The fluid level needs to be level with or near the bore opening.
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3.2.7BrakeFluidLevel
Check the brake fluid level daily or before operation.
1. Locate the sight gauge on the side of the Brake Fluid tank to observe the fluid level. See 3.3 "Ser-vice and Lubrication Points"s.
2. Add brake fluid as needed.
3. Inspect the brake lines and fittings for leaks.
4. Repair any leaks found before returning the unit to service.
5. When necessary, bleed the brakes.
6. Wipe up any spilled fluid.
3.2.8FuelLevel
1. Check the fuel level in the fuel tank using the fuel level gauge on the control panel.
2. Fill the fuel tank as needed, through its filler pipe. See 3.3 "Service and Lubrication Points".
3.2.9WindshieldFluid
1. Ensure cell drain valve is closed.
2. Fill fuel tank with correct fuel.
WARNING:
EXERCISE EXTREME CAUTION WHEN PERFORMING MAINTENANCE ONTHE HYDRAULIC BRAKE SYSTEM. FLUID ESCAPING UNDER HIGH PRES-SURE CAN CAUSE SERIOUS PERSONAL INJURY. A FACE SHIELD ANDPROTECTIVE CLOTHING MUST BE WORN.
STAY CLEAR OF ANY MOVING COMPONENTS. OTHERWISE, DEATH ORSERIOUS INJURY COULD RESULT.
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Notes
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3.3ServiceandLubricationPoints
Following are the service and lubrication locations for the MA-38
Figure2-3-2:ServiceandLubricationPoints
12
3
613
2
4
1
14 5
15
1110 9
8
7
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Table2-3-2:ServiceandLubricationPoints
3.4Adjustments
3.4.1FanBeltAdjustment
1. Stop the engine and remove the key.
2. Apply moderate thumb pressure to belt between the pulleys.
3. If tension is incorrect, loosen the alternator mounting bolts.
No. Description SpecificationCapacity
(Approximate)
1 Radiator Coolant Delo ELC 50/502.22 US gal
(8.4 L)
2 Engine Oil SAE 10W-302.51 US gal
(9.5 L)
3Steer Axle (Kings Pins, Links, and Tie Rod Ends)
Multi-purpose lithium-base grease As Required
4 Steer Axle Hubs/Front Wheel Bearing Multi-purpose lithium-base grease As Required
5 Automatic Transmission Dexron VI 5 qt. (4.7 L)
6 Hinged Hood Multi-purpose lithium-base grease As Required
7 Hitch Pin Multi-purpose lithium-base grease As Required
8 Newage Reduction Gear Box SAE 80W-90Included in New-age Drive Axle,*1.25 qt. (1.2 L)
9 Newage Drive Axle SAE 80W-90 2.6 US gal (10 L)
*5 qt. (4.7 L)
10 Brake Calipers Hypoid Gear oil, SAE 90 EP As Required
11 Drive Shaft Joints Multi-purpose lithium-base grease As Required
12 Brake Pedal Linkage Pivots Multi-purpose lithium-base grease As Required
13 Steering Gear Box (Manual Steering) Hypoid Gear oil, SAE 90 EP As Required
14 Hydro-Boost DOT3, Extra Heavy Duty As Required
15 Power Steering, Hydraulic Reservoir Dexron VI0.158 US gal
(.6 L)
16Operator Seat, Adjusting Slides (Not shown)
Multi-purpose lithium-base grease As Required
17 Windshield Reservoir (Not shown) Peak Windshield Wash 50/50 As Required
WARNING:
BE SURE TO STOP THE ENGINE AND REMOVE THE KEY BEFORE CHECK-ING THE BELT TENSION.
BE SURE TO REINSTALL THE DETACHED SAFETY SHIELD AFTER MAIN-TENANCE OR CHECKING.
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4. Then use a lever placed between the alternator and the engine block and pull the alternator outuntil the deflection of the belt falls within acceptable limits.
5. Replace fan belt if it is damaged.
3.4.2ServiceBrakeAdjustment
1. Remove master cylinder
2. Measure the distance between the inner face of the piston to the tip of the push rod.
3. Adjust the length as required to be within tolerance by turning the screw on the end of the push rodin or out.
3.4.3ParkBrakeAdjustments
The park brake lever is connected by mechanical linkage to the parking brake caliper on the transmission output shaft. When the lever is in the “lock” position, the mechanism activates the caliper which squeezes the pads and holds the tractor from moving. Perform the following steps to adjust the park brake:
1. Turn the knob on the lever to the right (clockwise) to tighten the brakes.
2. Turn it to the left (counterclockwise) to slacken the brakes.
3. Rotate the knob on the parking brake handle counterclockwise so the adjustment arm is approxi-mately 1” (25.4 mm) from the end of the adjustment range.
4. Loosen the set screw on the brake module housing and thread in the brake module housing untilthe pad assembly contacts the disk completely.
5. Back off the brake module until a flat on the housing lines up with the set screw and tighten the setscrew securely.
6. When necessary, the arm on the park brake caliper can be pulled off the spline and clocked up ordown. Reinstall locknut once arm is at desired angle and torque locknut to 9-12 lb-ft (12.2-14.9Nm).
7. Adjust the parking brake yokes by removing the clevis pins and threading the yokes in or out ofeach other until the brake pads are just about to engage the caliper when the park brake handle isin the released position.
8. Install new cotter pins to secure the clevis pins.
9. Engage parking brake and un-chock the wheels.
CAUTION:If belt is loosen or damaged and the fan is damaged, it could result in overheats orinsufficient charging.
NOTE: This length should be 9/10 in (+ 3/50 in) or 2.28 cm (+0.1524cm).
NOTE:Ensure the proximity sensor activates properly. With ignition on, the amber light on the back ofthe sensor should turn on when the park brake is released and turn off when it is applied.Prop
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3.4.4SteeringGearBoxAdjustment
1. Locate the adjustment screw opposite the Pitman arm spline on the right hand side of the steeringgear box.
2. Remove the drag link from the Pitman arm.
3. Loosen the lock nut on the adjusting screw.
4. Turn the adjusting screw clockwise or counterclockwise until the Pitman arm does not have anyfree play in it at the straight ahead position.
5. Turn the adjusting screw an additional eighth to a quarter of a turn in the same direction used toadjust it.
6. Tighten lock nut on adjusting screw.
7. Reinstall drag link.
3.4.5Toe-InAdjustment
The toe-in adjustment must be performed on both the rear side and front sides of tires. A level stretch ofpavement is that is flat and smooth for at least twenty feet (20 ft. or 6 m), is required for this adjustment.
3.4.5.1FrontSideofTires
1. Drive slowly forward with the cross spoke of the steering wheel at center, and run the unit straightwithout touching the steering wheel.
2. Apply the parking brake to stop the unit at the end of the run.
3. Place the toe-in gauge in front of the front tires and between the outside edges of the tires.
4. Ensure that the gauge is placed halfway up the tire sidewall (aligned with center of wheel).
5. Observe the number the needle is pointing to on the gauge. If the needle points to the number 2,the toe-in does not need any adjustment. If not, then continue to next step.
6. Remove the cotter pin and castellated nut from the tie rod end at the steering knuckle.
7. Adjust tie rod length as needed to achieve the needle pointing to the number 2 (1/8" or 3.175 mm)toe-in measurement.
8. Reinstall rod end, nut and new cotter pin once the needle points to the number 2 (1/8" or 3.175mm) and the appropriate toe-in is achieved.
9. Reconnect the rod.
10. Set toe-in gauge to the number 0 (90°).
3.4.5.2RearSideofTires
In order to properly adjust the rear toe-in, perform the same steps as the front toe-in adjustment on therear side tires.
3.4.6CabDoorAdjustment
To adjust a cab door:
NOTE: The needle should be pointing to number 2 (1/8" or 3.175 mm) on the toe-in side of the gauge.
NOTE: To decrease toe-in, turn the tie rod end clockwise and counter-clockwise to increase toe-in.
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1. Loosen the bolts on the hinges (2 per hinge).
2. Hold door in desired position
3. Tighten bolts to secure.
3.4.7VerticalHeadlightAdjustment
1. Loosen the nut on the horizontal bolt.
2. Aim headlight in desired position.
3. Tighten the nut.
3.4.8HorizontalHeadlightAdjustment
1. Loosen the nut on the vertical shaft that holds the entire headlight assembly to the rail.
2. Aim headlight in desired direction.
3. Tighten the nut.
3.4.9ShifterAdjustment
1. Place transmission in neutral and adjust the length of the cable to fit loosely in the transmission shiftcontrol lever.
2. Move hand lever to forward and reverse position.
3. Adjust the cable for best fit in all three positions.
3.5ServiceProcedures
3.5.1EngineOilandFilterChange
Change the engine oil just after the engine has been operated and it is still warm.
1. Place the unit on level ground.
2. Apply the parking brake and chock the wheels.
3. Place a warning tag on the control panel stating: “UNIT OUT OF SERVICE”
4. Place a catch pan below the engine oil drain plug.
5. Clean the area around the oil filter head.
6. Loosen and remove the engine oil drain plug.
7. Allow the oil to drain.
8. Install and tighten the drain plug.
9. Place a catch pan under the engine oil filter.
CAUTION:Oil could be very hot. Protect yourself when performing an oil change by wearing rub-ber gloves.
NOTE:Most contaminants are still suspended in the oil and will be carried out when the warm oildrains
NOTE: Oil will drain easier when the oil is warm.
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10. Use an oil filter wrench to loosen the oil filter for removal.
11. Remove the filter and empty its oil into the catch pan.
12. Inspect the filter mounting base assembly for deposits or dirt.
13. Remove any deposits on the filter gasket sealing surface and wipe the filter gasket sealing sur-face clean.
14. Apply thin coat of clean engine oil to the new filter gasket.
15. Screw in the cartridge by hand.
16. When the gasket contacts the seal surface, tighten the cartridge by hand.
17. Fill the engine crankcase as necessary to bring the oil level to the “H” mark on the dipstick.
18. Check the crankcase level with dipstick and remove the warning tag once the crankcase is full.
19. Start the unit.
20. After the new cartridge has been replaced, the engine oil level normally decreases a little. Thus,run the engine for a while and check the engine oil level.
21. Add oil if necessary.
22. Check the engine oil filter for leakage.
23. When needed, tighten the filter element with a strap wrench to stop any leaks
24. Return the unit to service.
3.5.2EngineAirFilterReplacement
1. Park the unit on level ground.
2. Apply the park brake.
3. Place a warning tag on the control panel stating: “UNIT OUT OF SERVICE”.
NOTE: If you tighten the cartridge with a wrench, it will be tightened too much.
CAUTION:Do not mix oils from different refiners or of different viscosities. To prevent over-fillingthe crank case, check the oil level frequently during filling. Oil leaks and bearing dam-age could otherwise result.
NOTE: Refer to the Kubota Manual provided in Chapter 5 for engine oil specifications.
NOTE: Engine oil pressure must be indicated on the gauge within 15 seconds after starting.
CAUTION:Shut off the engine immediately to avoid engine damage if oil pressure is not registeredwithin 15 seconds.
CAUTION:Ensure no debris or dirt enters the air filter housing while it is open. Dirt or debris lateringested into the engine can cause serious engine damage.
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4. Open the driver side enclosure to access the air filter assembly.
5. Release the cover latches and remove the service cover.
6. Remove and clean out the dust cup before it becomes half full with dust; usually once a week, orevery day if the working surroundings are dusty.
7. Remove the primary filter.
8. Wipe the inside air cleaner clean with cloth if it is dirty or wet.
9. When dry dust adheres to the filter, blow compressed air from the inside turning the filter. Pressureof compressed air must be under 30 psi (205 kPa).
10. Remove any accumulated dirt or debris from the filter housing.
11. Wipe the housing clean to ensure an air-tight seal to a new filter element.
12. Install the new primary filter.
13. Install the air cleaner dust cup with "TOP" indicated on the rear of the cup in the up position.
14. Re-install the service cover and fasten the four (4) cover latches.
15. Remove the warning tag and return the unit to service.
3.5.3TransmissionOilandFilterChange
1. Park the unit on level ground.
2. Apply the parking brake and chock the wheels.
3. Disconnect the battery from the vehicle.
CAUTION:
Since the air cleaner employed on this engine is a dry type, never apply oil to it.
Open the evacuator valve once a week under ordinary conditions or daily when used ina dusty place. This will get rid of large particles of dust and dirt.
CAUTION: Avoid touching the primary filter except when cleaning.
NOTE: Maintain reasonable distance between the nozzle and the filter.
NOTE:Replace the primary filter every year or every 6 cleanings. If the primary filter is stained heav-ily, replace it soon. At this time, replace the inner element too.
CAUTION: To protect the engine, do not remove the inner element in servicing the primary filter.
CAUTION:If the dust cup is mounted incorrectly, dust or dirt does not collect in the cup, anddirect attachments of the dust to the element will cause its lifetime to shorten to a greatextent.
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4. Place a warning tag on the control panel stating, “Unit is Out of Service.”
5. Jack up the unit at jack points and place jack stands under the unit as required.
6. Place a catch pan under the transmission drain plug located in the lower front of the transmissioncase.
7. Refer to the General Motor’s technician’s guide in (1.1 "Vendor Information") and perform detailedsteps as outlined.
8. Remove the warning tag from the control panel.
9. Remove the unit from the jack stands.
10. Start the engine and operate the unit for 15 minutes or until transmission fluid reaches an operat-ing temperature of 180-200ºF (82-93ºC).
11. Park Vehicle on a level surface.
12. Cycle through the gears every 3 seconds to allow the fluid to circulate stop on neutral (N).
13. Apply parking brake and let engine idle for 3 minutes.
14. Check the fluid level with the dipstick.
15. Add fluid as required to maintain the level in the safe operating zone.
16. Check the system for leaks before returning the unit to service.
3.5.4AxleGearBox
1. Park the unit on level ground.
WARNING:
TO AVOID INJURY TO PERSONNEL OR DAMAGE TO EQUIPMENT, ALWAYSUSE LIFTING EQUIPMENT, SAFETY JACKS AND CHAINS WITH A SAFEMINIMUM CAPACITY OF ONE AND A HALF (1.5)TIMES THE WEIGHT OFTHE VEHICLE BEING LIFTED.
TO AVOID INJURY TO PERSONNEL, NEVER WORK UNDER UNIT WHENUNIT IS SUPPORTED ONLY BY JACKS.
NOTE: The fluid must be within the hot cross-hatched area using the lowest level reading.
WARNING:
BEFORE CARRYING OUT ANY SERVICE WORK ALWAYS ENSURE THATTHE ENGINE IS SWITCHED OFF.
REMEMBER HOT OIL CAN CAUSE BURNS - WORK SAFELY - USE COM-MON SENSE.
CAUTION:
Before removal of the Axle for repair or overhaul carefully study the following proce-dures. Use Proper hand tools, slings and hoists for the job.
Keep all work areas, tools, and axle clean. All oil should be drained into a suitable con-tainer. Wipe up any spilled oil or fluids to prevent accidents. Wear correct safety equip-ment i. e. safety glasses and safety shoes to guard against personal injury.
All operations should be carried out by suitably qualified personnel and strictly inaccordance with the procedures detailed in the Newage or Axletech workshop manual.
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2. Apply the park brake.
3. Place a warning tag on the control panel stating: “UNIT OUT OF SERVICE”.
4. Place a container underneath to catch any escaping oil and drain.
5. Remove oil seals carefully to prevent damage if to be re-used, however to prolong the life of theaxle, it is best to replace these items.
6. If removing taper roller bearings for re-use keep them in matched set.
7. Protect all bearings from contamination.
8. Rinse all metal parts in solvent to remove dirt, grease, and oil.
9. Be careful to remove solvent from items before re-fitting.
3.5.5BrakeAssembly:WheelCylinderBleed
1. Park the unit on level ground.
2. Chock the wheels and apply park brake.
3. Jack the unit up and place jack stands under the unit.
4. Place a warning tag on the control panel stating: “UNIT OUT OF SERVICE”.
5. Disconnect the batter cables of the batteries.
6. Refer to the Newage service manual in Chapter 5 and perform detailed steps as outlined.
7. Check the brake fluid level in the hydraulic system reservoir; and add fluid as needed.
8. Reconnect the battery cables to the battery.
9. Remove the unit from jack stands.
10. Remove warning tag.
11. Drive unit under no load conditions to ensure brake system is operating properly.
12. Place unit back in to service.
3.5.6FuelFilterChange
1. Park the unit on level ground.
2. Turn off the engine.
3. Apply the parking brake.
4. Place a warning tag on the control panel stating: “UNIT OUT OF SERVICE”.
5. Close the fuel shutoff valve located on the underside of the fuel tank.
6. Place a container under the fuel filter to catch any escaping fuel.
7. Loosen p-clamp and hose clamps on the fuel Filter.
8. Replace filter.
9. Secure p-clamps and hoses on the filter.
WARNING:
IF USING CLEANING SOLVENTS THESE CAN BE TOXIC, FLAMMABLE, ASKIN IRRITANT OR GIVE OFF HARMFUL FUMES. AVOID PROLONGEDCONTACT, VAPOR INHALATION, OR SMOKING. FAILURE TO TAKE CARECAN RESULT IN INJURY OR DEATH.
WARNING: INSTALL THE POSITIVE BATTERY CABLE BEFORE THE NEGATIVE(GROUND) CABLE TO AVOID ELECTRICAL SPARKS AND BURNS.
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10. If the accumulation of dirt and water in the filter is excessive, remove the fuel tank.
11. Flush the Tank.
12. Blow out the line from the fuel pump to the tank.
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Chapter 2 Tow Tractor Model MA-38Section 4 Maintenance Manual
Section4:Troubleshooting
The following troubleshooting tables provide information for diagnosis and correcting problems with theMA-28 Tow Tractor. These tables should be used as quick reference guide to resolving minor commonerrors.
4.1EngineandTransmission
Table2-4-1:EngineandTransmissionTroubleshooting
WARNING:
TO AVOID INJURY TO PERSONNEL OR DAMAGE TO EQUIPMENT, ALWAYSUSE LIFTING EQUIPMENT, SAFETY JACKS AND CHAINS WITH A SAFEMINIMUM CAPACITY OF ONE AND A HALF (1.5)TIMES THE WEIGHT OFTHE VEHICLE BEING LIFTED.
TO AVOID INJURY TO PERSONNEL, NEVER WORK UNDER UNIT WHENUNIT IS SUPPORTED ONLY BY JACKS.
Problem Cause Correction
1 Loss of power
Reduction in pulling power. Check transmission per appendix.
Engine power is reduced. Check engine per appendix.
Rear axle is damaged.Check rear axle for damage and proper oil level.
Brakes are dragging.Check for stuck service and park brake pads.
2White exhaust gas
is observed
Excessive engine oil. Reduce to specified level.
Piston ring and liner worn or stuck.
Replace.
Defective valve stem seal. Replace.
3Excessive black exhaust gas is
observed
Fuel system is bad. Check the fuel system.
Fuel is extremely poor quality. Replace fuel.
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Tow Tractor Model MA-38 Chapter 2 Maintenance Manual Section 4
4
4Difficult to Start
Engine
Fuel doesn't flow.
Check the fuel tank, fuel filter, fuel hoses and fuel pump.
As fuel will be filtered by the filter, if there should be water or other for-eign matters on the filter, clean the filter.
Valve clearance is not as speci-fied.
Adjust valve clearance when the engine is cold.
Engine oil becomes thick in cold weather and engine cranks slow.
Change grade of oil according to the weather (temperature).
Low compression
Bad valve or excessive wear of rings, pistons and liners cause insuf-ficient compression. Replace with new parts.
Battery is discharged and the engine will not crank.
Charge battery.
In winter, always remove battery from machine, charge fully and keep indoors. Install in machine at time of use.
Clogged air cleaner Clean or replace.
Spark plug electrodes are wet with gasoline.
Dry electrode and restart.
Defective starter. Repair or replace.
Defective main switch. Repair or replace.
Vapor LockCheck fuel hose plumbing is correct and fuel hoses are not routed next to hot components.
Disconnection Check the wire harness.
Problem Cause Correction
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Chapter 2 Tow Tractor Model MA-38Section 4 Maintenance Manual
5When output is
insufficient
Compression is insufficient.
Bad valve or excessive wear of rings, pistons and liners cause insuf-ficient compression. Replace with new parts.
Fuel is insufficient. Check fuel system.
Overheating of moving parts.
Check lubricating oil system.
Check to see if lubricating oil filter is working properly.
Filter element deposited with impuri-ties would cause poor lubrication. Change element.
Check to see if the clearance of bearing is within factory specs.
Valve clearance is not as speci-fied.
Adjust valve clearance when the engine is cold.
Air cleaner is dirty. Clean or replace.
Defective spark plug. Clean or replace.
Defective ignition coil. Replace.
Disconnection Check the wire harness.
6Engine suddenly
stops
Lack of fuel.
Check the fuel tank and refill the fuel, if necessary.
Also check the fuel system for air or leaks.
Moving parts are overheated due to shortage of lubrication oil or improper lubrication.
Check amount of engine oil with oil level gauge.
Check lubricating oil system.
Replace oil filter cartridge.
Vapor LockCheck fuel hose plumbing is correct and fuel hoses are not routed next to hot components.
Clogged air cleaner Clean or replace.
Disconnection Check the wire harness.
7Lubricant oil con-
sumption is exces-sive.
Oil leaking from oil seal, gasket, etc.
Replace.
Defective valve stem seal. Replace.
Piston ring and liner worn or stuck.
Replace.
Problem Cause Correction
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Tow Tractor Model MA-38 Chapter 2 Maintenance Manual Section 4
4
4.2AlternatorTable2-4-2:AlternatorTroubleshooting
8 Engine overheats
Engine oil insufficient.Check oil level. Replenish oil as required.
Fan belt broken or elongated. Change belt or adjust belt tension.
Coolant insufficient. Replenish coolant.
Excessive concentration of anti-freeze.
Use only specified pre-mixed cool-ant.
Radiator net or radiator fin clogged with dust.
Clean net or fin carefully.
Inside of radiator or coolant flow route corroded.
Clean or replace radiator and parts.
Defective fan or radiator or radia-tor cap.
Replace defective parts.
Defective thermostat.Check thermostat and replace if necessary.
Defective temperature sensor.Check temperature with thermome-ter and replace if necessary.
Overload running. Reduce load.
Head gasket defective or water leakage.
Replace parts.
No. Problem Cause Correction
1 Noisy alternator
Loose alternator belt.Check mounting, pulleys, and belts for correct tension and tightness.
Alternator bearings worn or dam-aged.
Replace alternator.
2Alternator output consistently high
Incorrect wiring.Check wiring connections at alter-nator and battery.
High electrical system load.Check for high current draws in electrical system.
Problem Cause Correction
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Chapter 2 Tow Tractor Model MA-38Section 4 Maintenance Manual
4.3RearAxleTable2-4-3:DriveAxleTroubleshooting
4.4SteeringTable2-4-4:SteeringTroubleshooting
Problem Cause Correction
Rear axle noise
Low oil.Check lubrication level. Top off as needed.
Dirty drop box oil.Check drop box magnetic plugs for metal chips.
Dirty axle oil.Check axle magnetic plugs for metal chips.
Damaged wheel bearings.Check bearings for damage and proper lubrication.
Damaged internal axle components.Tear down and inspect axle and drop box. Repair or replace damaged parts.
No. Problem Cause Correction
1Manual steering
difficult
Steering gearbox not lubricated. Check lubrication.
Drag link joints not greased. Add grease to joints.
King pins not greased. Add grease to kin pin.
2Power steering
difficult
King pins not greased. Add grease to kin pin.
Hydraulic system contaminated.Flush hydraulic system and replace fluid with clean fluid.
Damaged steer valve.Check valve, replace if damaged or faulty.
Worn/damaged steer cylinder.Replace steer cylinder or repair seals.
3Front wheel
appears to wobble
Lug nuts loose. Torque lugs to proper value.
King pin worn. Check studs and king pins.
Wheel bearing worn.Check bearings and hubs. Repair or replace as required.
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Tow Tractor Model MA-38 Chapter 2 Maintenance Manual Section 4
4
4.5BrakeSystemTable2-4-5:BrakeSystemTroubleshooting
4Steering wanders
or weaves
Wheel bearings worn or not lubri-cated.
Replace wheel bearings or lubricate as necessary.
Toe-in mis-adjusted. Check toe-in and adjust.
Steering gearbox loose.Check steering gearbox mountings and tighten as necessary.
Steering gearbox has too much backlash.
Check steering gear box for back-lash adjustments or replace gear-box if gears are worn.
5Vehicle pulls to one
side
Brakes are dragging.Check brakes and replace calipers as necessary.
Wheel bearings seized. Check wheel bearings.
Tires are mis-matched, mis-inflated, or differently worn.
Check tire “match” and inflation.
No. Problem Cause Correction
1Excessive stopping
distance
Brake pads worn.Check brakes pads for glazing or excessive wear. Place as neces-sary
Brake fluid under-filled or bad.Check fluid level and refill if neces-sary. Flush and replace fluid if past PM cycle.
Air in brake circuit. Bleed Brakes.
2Brakes drag or
uneven pullBrake pad dragging.
Check pads and rotor for damage or incorrect parts. Check for seized pistons.
3Brake spongy or excessive travel
Brake system fluid leak.Check fluid lines, fittings, and mas-ter cylinder for leaks.
Air in brake circuit. Bleed brake system.
4 Hard pedal
Brake booster (where applicable) not getting adequate hydraulic flow.
Check hydraulic pressure relief valve is adjusted to 850 PSI (5.86e+6 kPa).
Brake booster (where applicable) is damaged.
Check booster for pressure or leak-ing.
Seized brake pedal. Inspect brake pads and rotor.
No. Problem Cause Correction
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Chapter 2 Tow Tractor Model MA-38Section 4 Maintenance Manual
4.6ElectricalSystem4.6.1Battery
Table2-4-6:BatteryTroubleshooting
4.6.2Lights(12VoltSystem)
Table2-4-7:LightsTroubleshooting
Problem Cause Correction
Battery will not stay charged
Battery is worn out.Check for low battery voltage (indicat-ing dead battery). Replace battery.
Alternator is not charging battery. Check alternator output & belts.
Wire is broken. Check for breaks in wiring.
Component is draining battery with ignition off.
Check for large current draw with vehi-cle off.
No. Problem Cause Correction
1Poor, intermittent, or
no headlight
Blown fuse or tripped circuit breaker.
Check fuse or circuit breaker.
Headlight burned out. Replace LED Bulb.
Switch damaged.
Check headlight switch (or pres-sure switch on transmission if headlights are wired through trans-mission).
Wired incorrectly.Check wiring & ground connec-tions.
2Poor, intermittent, or
no stop lights
Blown fuse or tripped circuit breaker.
Check fuse or circuit breaker.
Taillight burned out. Check bulbs or lamps.
Brake pressure switch damaged. Check brake light switch.
Wired incorrectly.Check wiring and ground connec-tions.
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Tow Tractor Model MA-38 Chapter 2 Maintenance Manual Section 4
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4.6.3WiperMotor
Table2-4-8:WiperMotorTroubleshooting
3Poor, intermittent, or
no back-up lights
Blown fuse or tripped circuit breaker.
Check fuse or circuit breaker.
Back-up light burned out. Check bulbs or lamps.
Mis-adjusted switch or bad relay.Check reverse switch under shifter or reverse relay.
Transmission software incorrect.
Check that TCM is grounding when vehicle is in reverse (if reverse wired through TCM and reverse relay. Check schematic to confirm).
Wired incorrectly.Check wiring and ground connec-tions.
4Poor, intermittent, or no turn signal lights
Blown fuse or tripped circuit breaker.
Check fuse or circuit breaker.
Bad flasher relay. Check relay.
Turn signal light burned out. Check bulbs or lamps.
Wired incorrectly.Check wiring, connections, and grounds.
5Poor, intermittent, or no cab marker lights
Blown fuse or tripped circuit breaker.
Check fuse or circuit breaker.
Broken switch. Check relay or switch.
Wired incorrectly. Check wiring & connections.
Cab marker lights burned out.Check sockets, bulbs, or lamps. Replace bulb/lamps as required.
Problem Cause Correction
Wiper motor works intermittently, or will
not work
Blown fuse or tripped circuit breaker.
Check fuse or circuit breaker.
Wired incorrectly.Check wiring and ground connec-tions.
Broken switch. Check wiper control switch.
Burned out motor. Check motor.
No. Problem Cause Correction
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Chapter 2 Tow Tractor Model MA-38Section 4 Maintenance Manual
4.6.4Horn
Table2-4-9:HornTroubleshooting
No. Problem Cause Correction
1Horn work intermit-tently, or no sound
Blown fuse or tripped circuit breaker.
Check fuse or circuit breaker.
Bad horn relay. Check relay.
Wired incorrectly.Check wiring, horn button, and grounds for horn button and switch.
Burned out speaker. Check horn speaker.
2Horn sounds contin-
uously
Wiring short.Check for shorted wire between horn button and relay.
Damaged horn button. Check for a stuck horn button.
Relay stuck closed. Check relay.
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Tow Tractor Model MA-38 Maintenance Manual
Chapter 2Section 4
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CD444-38M 2 - 5 - 1July 2019 (Rev A)
Chapter 2 Tow Tractor Model MA-38Section 5 Maintenance Manual
Section5:SystemSchematics
This section provides electrical and hydraulic information for diagnosing and correcting problems with theMA-38 Tow Tractor.The following pages display schematics to assist in the location of electrical wiringand hydraulic routing.
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Chapter 2Section 5
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Chapter 2 Tow Tractor Model MA-38Section 5 Maintenance Manual
CD444-38M 2 - 5 -3July 2019 (Rev A)
5.1ElectricalSchematics
Figure2-5-1:MA-38StandardElectricalSchematic7188829_RevB(Page1of6)
118
80
12 VOLTBATTERY
93
G7
HORN
SWITCHHORN
NEUTRALRELAY
85
86
104
87
3090
SWITCHIGNITION
6
2
1
5
3 4
P19
(D27)
MASTERRELAY
87
30
86
85
(D10)
(D25)
80 REVERSERELAY
85
86
87
30
HORNRELAY
85
86
87
30
F6 15 AMP
F5 10 AMP
F3 15 AMP
F8 CIRCUIT BREAKER 15 AMP
F9 15 AMP
F7 15 AMP
F2 15 AMP
F1 CIRCUIT BREAKER 15 AMP
FUSE BOX
GROUND BUSBAR (D23)
12
11
10
98
7654321
-
117
93
N
93
IGN2
12
IGN
2
R
IGN15
117
HORN PWR
HORN PWR
HO
RN P
WR
HO
RN P
WR
HO
RN P
WR
HORN PWR
104
IGN3
103
IGN8
IGN8
103
13 SHEET 2
SHEET 6IGN1
114P SHEET 2
IGN4
IGN
7
112 SHEET 2IGN4
IGN11
IGN7 IGN7
IGN11 66 SHEET 4
115 115 SHEET 3
IGN10 IGN10
TCU BAT SHEET 3BA
T1
BAT1
BAT1
TCU IGN SHEET 3
IGN5
F4 15 AMP
113 113
IGN6
63
IGN9
P2
IGN
1
IGN2
SHEET 2
SP1114
P2
SP36
SHEET 5
MVP1
ECM
P266
114
P2
P2
P263
IGN1
IGN3
D27
P2
103
P2
IGN
15
G1 SHEET 3G2 SHEET 3G3 SHEET 2G4 SHEET 2G5 SHEET 3
G6 SHEET 4
G7
G7
G7
G7
G8 SHEET 4
G9 SHEET 3
P212
SHEET 213
(OPTION)
P2112
P2
NP2
P2
TCM BATP2
TCM IGNP2
POWERSTUD
ENGINESHEET 6
SHEET 6
R
G10 SHEET 2
ALL
IGN
WIR
ES
ALL IGN WIRES
SPL
SPL
HBAT
(HALL SYSTEM)SHEET 2
(BOTTOMOF STARTER)
NOT USED
NOT USED
ORHALL SYSTEM
(OPTION)
1, 2, 4, 5, AND 6ARE CONNECTED
DURING START
1, 3, 4, 5, AND 6ARE CONNECTEDDURING IGNITION
SHEET 6
SHEET 6
GROUNDSTUD
ENGINETO
1
11
14
13
10
12
6
7
5
8
32
4
15
9
SHT 3
SHT 3
SHEET 5
SHEET 5
SHT 6
TO STARTER
12
7
4
9
5 21
6
1122
20
14
28
26
30
16
18
24
8
3
10
12
19
13
27
25
29
15
17
23
CB
CB
CB
CB
CB
CB
CB
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Tow Tractor Model MA-38 Chapter 2Maintenance Manual Section 5
Figure2-5-2:MA-38StandardElectricalSchematic7188829_RevB(Page2of6)
RIGHT FRONTHEAD LIGHT
LEFT FRONTHEAD LIGHT
PSWITCH
BRAKE LIGHTPRESSURE
BRAKE/TAIL LIGHTRIGHT REAR
BRAKE/TAIL LIGHTLEFT REAR
54
53
106
107
- +
SHIFTERBACK LIGHT
83
D5
D3
D5
D3
D8
D8
D7
D7
(D1)
-+
BRAKE WARNING PRESSURE SWITCH
10
BRAKE WARNING LIGHT
BRKWRN
BRKWRN
P
1
2
110
FUELSENDER
PRESSURE
P
SWITCHPRESSURE
TRANSMISSIONNO
(N.O.)
P25
1 2 3 4 5 6 1 2 3 4 5 6
P24
MVP1
MVP
1
CAN
H+
SHEET 3
CAN
L-
SHEET 3
G4
P88
FOOT
5+VD
C
5+VD
C1
5+VDC2
5+VD
C2
APS
2
APS2
APS
2
APS2
111
111
APS
1 SI
G
GN
D
GND
SP30
APS
1 G
ND
APS2 GND
APS
2 G
ND
84
114SHEET 1
SP2
RIGHTREV LIGHT
SP5LEFT
REV LIGHT
12
SHEET 1
OR(OPTION)
(OPTION)
(D11)
D7
D7
REVERSEALARM
D28
SP8
SP37
95
7189
84
101
83A
D7
HEADLIGHT SWITCH OPTIONS(D20)
THROTTLE
78
77
D7
G3
MVP DISPLAY
SP4
D7
D7
(SHEET 4)
(SHEET 4)
G6
G6
12
83D8
(TURN SIGNAL OPTION SHEET 4)
1
2
APS1
G6
95 G6
STD
(OPTION)
95
WIRED TO IGN)(HEADLIGHTSNO SWITCH
(OPTION)
BOTTOM OF PAGESEE OPTIONS
(D20)
(OPTION)
CN12A CN12B
NC
NC NC
(LOCATION: DASH)
G6
SHEET 4G6
G6 SHEET 4
G6 SHEET 4
12
12
120 OHMS
D
E
F
B
A
C
13
OR
95
WIRED TO IGN)(HEADLIGHTSNO SWITCH
(OPTION)
AND
89
101
71 89
101
71 89
101
71
+
-
BATT
ERY
STA
RT
IGN
/ACC
HALL 12V CONTROLLER
4-PIN TWIST LOCK CONNECTOR
GREEN ILLUMINATED PUSH BUTTON IGNITION
G10
OUT OF FUEL SIGNAL
2
3
1
4
5
6
GRA
Y
RED
BLU
E
GLOW PLUG SIGNAL
ORANGE
BLACK
PURPLE
SHEET 1
NOT USED NOT USED
CONNECT TO P19
(OPTION)
P31P5
P31P5
NORMAL OPERATION:LOW FUEL(240 OHMS)-HIGH FUEL(33 OHMS)APS1 MIN(0.9V)-MAX(3.6V)APS2 MIN(0.5V)-MAX(1.7V)
1
1
2
2
4
5
9
9
2
1
12
74
3
6
1
2
SHT 1
SHT 4
SHT 1
SHT 1
SHT 1
SHT 4
SP31
SP28
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CD444-38M 2 - 5 -5July 2019 (Rev A)
Figure2-5-3:MA-38StandardElectricalSchematic7188829_RevB(Page3of6)
1
18 A
WG
YEL
+12
V
3
20 A
WG
BLK
GN
D
4 8 2
GRY
/ORN
SIG
NA
L BE
LT U
P SE
NSO
R
7
7
BRN
/BLK
SIG
NA
L
29
5
8
S5
123 4
18 A
WG
YEL
+12
V
20 A
WG
BLK
GN
D
20 A
WG
BLK
GN
D
S6
GRY
/YEL
SIG
NA
L
20 A
WG
BLK
GN
D
PC5ATH
MHTH
WH
T/RE
D C
AN
1 H
TWISTEDPAIR
18 AWG BLK GROUND
6
18 A
WG
YEL
+12
V
TCU
TWISTEDPAIR
TWISTEDPAIR
TWISTEDPAIR
WH
T/BL
K CA
N1-
LTWISTED
PAIRTWISTED
PAIR
WHT/BLK CAN1-L
WHT/RED CAN1 H
18 AWG YEL +12V
4L70E 2010 SPECIAL TRANSMISSION (INCHING) TCU MODULE 2800
C6 PC5A
C5C61C8 2 3 4 5 6 7 8
YEL/
RED
AN
A IN
2
YEL/
LT.G
RN A
NA
IN 3
YEL/
LT.B
LU A
NA
IN 4
YEL/
WH
T A
NA
IN 5
VIO
/WH
Y PW
M 5
VIO
/ORN
PW
M 6
PNK/
WH
T D
IG O
UT
5
PNK/
ORN
DIG
OU
T 6
1C7 2 3 4 5 6 7 8
46 47 48 49 51 52 55 56 10 30 31 32 33 34 35 36
GRY
/PN
K D
IG IN
8
BRN
/RED
DIG
IN 1
0
BRN
/LT.
BRN
DIG
IN 1
1
BRN
/LT.
BLU
DIG
IN 1
2
BRN
/WH
T D
IG IN
13
BRN
/ORG
DIG
IN 1
4
BRN
/YEL
DIG
IN 1
5
BRN
/PN
K D
IG IN
16
92
17 G2
V-
V+
SIG
PX
1 2 34
NO
T U
SED
P30
90
PX
PARK BRAKEPROXIMITY SENSOR
(PNP)+12V W/ BRAKEDISENGAGED
G2
NO
TU
SED
NO
TU
SED
NO
TU
SED
NO
TU
SED
NO
TU
SED
NO
TU
SED
SWITCH
SHIFT
PRESSUREP
G5
INHIBIT
(D2)
BRAKE
NO
TU
SED
ENABLESHIFT
LIGHT
18
SPL 34
(INDICATES SHIFTING ABILITY)
(SEL)
1
2
17
17115SHEET 1
NSHEET 1
RSHEET 1
NO
TU
SED
NO
TU
SED
NO
TU
SED
NO
TU
SED
NO
TU
SED
NO
TU
SED
NO
TU
SED
BAC5
CAN INTERFACE DIAGNOSTIC PLUG
CA
N H
I +
CAN
LO
W -
SHIE
LD G
ND
G9
C
SP 22
SP 23
CANL-
CAN
H+
CANL-
CAN
L-
(LOCATION: LH RAIL FRAME)
SHEET 4
SHEET 4CANH+ CANH+SHEET 2
SHEET 2
CAN
H+
CAN
L-
SHEET 4
SHEET 4
SHEET 4
SHEET 4
MAIN HRN
SHT 1
SHT 1
SHT 1
SHT 5 SHT 5
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Tow Tractor Model MA-38 Chapter 2Maintenance Manual Section 5
Figure2-5-4:MA-38StandardElectricalSchematic7188829_RevB(Page4of6)
8
WH
T/RE
D C
AN
1 H
S3
15
12
42
S2
18 A
WG
BLK
GRO
UN
D
GRY
/WH
T D
I-5
PNK/
LT G
RN C
K TR
AN
S LT
40
5
1P3
11
TCU
IGN
TCU
IGN
YEL
12VO
LTS
IGN
10
20
RED
+12
V BA
TTTC
U B
AT
2 3
ORG
/BLK
TACH
IN
G1
1
WH
T/BL
K CA
N1-
L
16
S4
7
6
MAIN HRN
TRANS
24
TCU BAT
TCU IGN
C4
ORG
+5V
SEN
S
21 45
WH
T TP
S SI
G
BLK
SIG
GN
D
9 46
DHMH
C4A
OUTPUTSHAFTSPEED
SENSOR
B
ORG
/RED
TO
SS +
BLK/
WH
T SE
NSO
R G
ND
2523
AC3
OPTIONALCOM
NOT REQUIREDFOR USE
B
RED
SER
IAL
RX
WH
T RS
232
GN
D
2728
C
BLK
SERI
AL
TX
26
C2
53
A
4L70E TRANSMISSION (INCHING)
B
PWM
8-PN
K/RE
D-S
HIF
T SO
L B
PWM
7-PN
K/BL
K-SH
IFT
SOL
A
C
18 A
WG
-YEL
-LIIN
E PR
ESS
+
PWM
1-VI
O/B
LK-L
INE
PRES
S -
E
18 A
WG
-YEL
-PO
WER
F
DN
1-G
RY/B
LK-IM
S A
G
DN
2-G
RY/R
ED-IM
S C
H
DN
3-G
RY/L
T G
RN-IM
S B
JK L
DN
4-G
RY/L
T BL
U-IM
S P
ORN
/LT
GRN
-TU
RB S
PEED
+
AD
6-YE
L/O
RN-T
FT
M R S T
BLK/
WH
T-SE
NSO
R G
ND
VIO
/LT
GRN
-FW
D-C
L
VIO
/BLU
-REV
-CL
VIO
/WH
T-TC
C O
N/O
FF
VIO
/RED
-TCC
PW
M P
RESS
U
1119 2 3 4 538 50 9 13 14 41 12BL
K/W
HT-
IMS
GN
D
BLK/
WH
T TU
RBO
SPE
ED -
37
NV
S7
S1
54 18
DP W
4L70E TRANSMISSION (INCHING) TCU MODULE 2800
TWISTEDPAIR
TWISTEDPAIR
C1
YEL 12VOLTS IGN
18 AWG YEL +12V
BLK SIG GND
CANL-
CANH+
18 AWG YEL +12V
BLK SIG GND
CAN1-H
CAN1-L
GND
+12V
NO
TU
SED N
OT
USE
D
NO
TU
SED
NO
TU
SED
NO
TU
SED
NO
TU
SED
NO
TU
SED
SHEET 1
SHEET 1
SHEET 1
APS
1 SI
G
APS1 SIGSHEET 2
SHEET 3
SHEET 3
SHEET 3
SHEET 3
SHEET 3
SHEET 3
NO
TU
SED
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Chapter 2 Tow Tractor Model MA-38Section 5 Maintenance Manual
CD444-38M 2 - 5 -7July 2019 (Rev A)
Figure2-5-5:MA-38StandardElectricalSchematic7188829_RevB(Page5of6)
FRONTWIPERMOTOR
FRONTWIPER
SWITCH
66W
HT
BLK
62 G8
CABHEATERMOTOR
M
M
6365
HEATERSWITCH
SWITCH
DOMELIGHT
DOMELIGHT
D7
(D17)
113SHEET 1
LED LIGHTBEACON
FLASHING/
LT20
FLASHUNIT
YEL
BEACONPROGRAMING
WIRE
+
-
ROTATING
63SHEET 1
HL
M FANVENTILATION
(OPTION)
CAB
M4
G8
68
C
WORKLIGHTSWITCH(D29)
116
OPTION
+
-WORKLIGHT
8383
54
56
53
5451
+
PILOT LT
CONTROL SWITCHTURN SIGNAL
83
58
-52
51
53
LEFT FRONTTURN LT
RIGHT FRONTTURN LT
5556
LED TURN
FLASHERSIGNAL
XL
1N5406DIODE
1N5406DIODE
SHEET 2
SHEET 2
SP6
(D8)
OPTIONAL LED TURN SIGNAL CONTROLLER WIRING
(D6)
RIGHT REARTURN LT
(D7)
55A
SP 7
55
(D4)
10
LEFT REARTURN LT
(D7)
56A11
83SHEET 2
D7
D7
G6
SHEET 2
SHEET 2
SP3
G6
SHEET 1 G6
SHEET 2
G6
G6
G6
G6
G6
G6
G6
G6
(D9)
1
7
5
4
3
1
2
12
2
58
58
58
(D26)
(D21)
6
8 G6
CAB HRN
MAIN HRN
(OPTION)
(OPTION)
+
-
MAIN HRN
CAB HRN
G6
G6
63
113
G6
68
5
9
9
9
SHT 1SHT 1SP35
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2 - 5 -8 CD444-38MJuly 2019 (Rev A)
Tow Tractor Model MA-38 Chapter 2Maintenance Manual Section 5
Figure2-5-6:MA-38StandardElectricalSchematic7188829_RevB(Page6of6)
ENGINE VIC1
(RED) 109
PUMPFUEL
M (WHT) 108
(P1)
117SHEET 1
ECMSHEET 1
ALL SWITCHES, RELAYS SHOWN IN DE-ENERGIZED POSITIONSALL SWITCHES, RELAYS SHOWN IN DE-ENERGIZED POSITIONS
C
D
F
A
P
N
(D30)
SHEET 3
SHEET 3
CANL-
CANH+
MANIFOLD
FUELPRESSURE
(TO ENGINE POWER STUD)
(TO ENGINE POWER STUD)
+ -
TWISTED PAIR
R
E
G
H
B
L
J
S
M
K
NOT USED
NOT USED
NOT USED
NOT USED
NOT USED
NOT USED
NOT USED
NOT USED
NOT USED
NOT USED
NOT USEDNOT USEDNOT USED
NOT USEDNOT USED
NOT USED
NOT USED
NOT USED
NOT USED
NOT USEDNOT USEDNOT USED
NOT USED
ENGINE HARNESS
NOT USED
ALL FUSES AND RELAYS LOCATED IN ENGINE FUSEBOX ON SHEET 1
1 2
2 1
SHEET 1
GROUNDSTUD
ENGINE
SHEET 1(TO BATTERY GROUND)
(TO BATTERY GROUND)
SHT 1
SHT 1
SPK_COIL1A
SPK_COIL2B
SPK_COIL2A
SPK_COIL1B
INJ1_LS
INJ4_LS
INJ2_LS
INJ3_LS
KNK1-
KNK1+
CAM-
CAM+
CRANK+
MAP
STARTER
AUX_PWM5 REC
DBW-
TPS1
AUX_ANA_PU3
DBW+
GOV1
EGOH_1
EGO2
EGOH_2
CAN1-
5V_EXT1
GND
ECT
OIL PRESS
AUX_ANA_PD2
AUX_PWM2
GND
5VRTN1
SPK_GND
AUX_ANA_PD1
CAN1+
SPEED+
AUX_DIG3
AUX_DIG2
TPS2
AUX_PWM5
SPEED-
EGO1
AUX_DIG4
AUX_ANA_PU2
IAT
AUX_PWM6
VSW
AUX_PWM3
RELAY
MIL
5V_RTN2
5V_EXT2
FPP1
AUX_ANA_PU1
AUX PWM3_REC
TACH
1 2
1 2
1 2
1 2
21
21
21
1 2
1 2
1 2
21
CRANK-
ABCD
1 2 3
4 5 6
A C
B D
B D
A C
1
1
Joint A
FPP2_IVS
VBAT
AUX PWM1
A
B
C
D
5A FUSE
30A FUSE
15A FUSE
15A FUSE
1
5
3
2
64
67
65
66
52
5126
25
27
28
23
36
82
80
48
47
21
62
22
61
14
15
19
20
35
37
38
13
53
31
54
32
87
74
79
73
90
44
78
89
72
83
84
43
85
39
40
42
34
50
41
29
30
12
469
81
ECM(2/2)
COIL_CYL_#1
COIL_CYL_#2
COIL_CYL_#3
COIL_CYL_#4
INJ_CYL_#1
INJ_CYL_#2
INJ_CYL_#3
INJ_CYL_#4
Joint A
Knock sensor
Crank sensor
Cam sensor
Joint CJoint D
TMAP(BOOST)
Joint CJoint D
Joint A
Joint DJoint A
Joint D
Throttle actuator
O2 sensorPost Catalyst
O2 sensorPre Catalyst
DIAG_TOOL Connector
CAN Tool
Coolant Temperature Sensor
Oil Switch
Joint C
Joint D
Joint A
Alternator
Starter
STARTER
Starter Relay
VSW
Fuel Pump Relay
FUEL PUMP
Power Relay
ECM
ECM(1/2)
Joint D
Joint C
2
Joint D
10A FUSE
Joint A
IGNITION
A
B
C
D
60A FUSE
Joint C
Joint D
50A FUSE
POWR_FMOLEX 19432-0013
POWR_MMOLEX 19433-0013
EFFECTIVE ON SERIALNUMBER 2023056
Propert
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Chapter 2 Tow Tractor Model MA-38Section 5 Maintenance Manual
CD444-38M 2 - 5 -9July 2019 (Rev A)
5.2HydraulicSchematics
Figure2-5-7:MA-38HydraulicSchematicHYD-MA-28
2
1
ENGINE
1300 PSI
PT
L
R
3
4
1 1
2 ENG-MA-27-PS-2 HYDRAULIC PUMP 1
4
ENG-MA-27-PS-1
STEER CYLINDER 1
3 660-1-3028 CHARLYNN POWER STEERING VALVE 1
RESERVOIR
TM1-2-8032
Propert
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THIS PAGE INTENTIONALLY BLANK
Tow Tractor Model MA-38 Chapter 2Maintenance Manual Section 5
2 - 5 -10 CD444-38M July 2019 (Rev A)
Propert
y of A
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