AGCO ST55 Tractors Repair Manual

$34.00

🚜 Equipment
Brand	AGCO
Type	Compact Tractors
Model	ST55
📄 Documents
Type	Repair Manual
Publication	79028168
Language	English
Format	PDF
No of Pages	557

Preface

INTRODUCTION
This service manual has been prepared with the latest service information available at the time of publication. Read the service manual carefully before performing any service on the compact tractor. This manual is one of the most important tools available to the service technician.

UNITS OF MEASUREMENT
Measurements are given in metric units followed by the equivalent in US units. Hardware sizes are provided in millimeters for metric hardware and in inches for U.S. hardware.

TABLE OF CONTENTS
A Table of Contents is located at the front of this manual. The Table of Contents shows the divisions, and each individual division also includes its own Table of Contents.

PAGE NUMBERS
All page numbers are composed of two numbers separated by a dash, such as 01-25. The number before the dash represents the division number, and the number following the dash is the page number within that division. Page numbers appear at the lower right or left corner of each page.

Table of Content

📙 Table of Contents

Cover

Cover

01 – General Information

01 – General Information

02 – Major Components

02 – Major Components
- ST55 Tractor Service Manual
  - 02 Major Components
    - General Precautions
      - General Precautions for Separation and Installation
        Before Operation
      - Precautions to be Followed When Installing Standardized Parts
        Roller or Ball Bearings
        Oil Seals
        O-Rings
        Snap Rings
        Spring (Roll) Pin
        Cotter Pins
        Bolts and Nuts
        Other Precautions
        Precautions for Applying Adhesives
        Component Sealant
    - Separation Of Major Components
      - Gear Train
      - Front Wheel Drive Shaft (4WD)
        Removal and Installation
      - Front Axle and Front Axle Bracket
        Removal
        Installation
      - Front Frame Separation From Engine
        Removal
        Installation
      - Splitting Tractor Between Engine and Front Transmission
        Removal
        Assembly
        Input Gear Removal From Front Transmission
        Assembly
      - Splitting Tractor Between The Front Housing and Spacer Housing
        Disassembly
        Main Change Gears
        Assembly
      - Splitting Tractor Between Spacer Transmission and Differential (8 x 8 Transmission Only)
        Disassembly
        Assembly
        Splitting Tractor Between Spacer Transmission and Differential (12 x 12 Transmission Only)
        Disassembly
        Assembly
    - Sheet Metal and Three-Point Hitch
      - Hood Side Panels
        Remove and Installation
      - Front Grill
        Remove and Installation
      - Hood
        Remove and Installation
      - Steering Column Cover
        Remove and Installation
        Instrument Panel
      - Shroud Around Instrument Panel
        Remove and Installation
      - ROPS Frame and Seat Belt
      - Fender
        Remove and Installation
      - Seat
        Remove and Installation
      - Seat Suspension
        Remove and Installation
      - Floor With Fenders
        Remove and Installation
      - Platform Mounts
        Remove and Installation
      - Muffler
        Remove and Installation
      - Drawbar
        Remove and Installation
      - Drawbar Bracket
        Remove and Installation
      - Category 1 Hitch Specifications
      - Top Link
        Remove and Installation
      - Lift Rod or Lower Link (One Side)
        Removal and Installation
      - Check Chain
        Remove and Installation
    - Index

03 – Cooling, Air Cleaner, And Fuel Systems

03 – Cooling, Air Cleaner, and Fuel Systems
- ST55 Tractor Service Manual
  - 03 Cooling, Air Cleaner, and Fuel Systems
    - Cooling System
      - General Description
      - Radiator
        Specifications
        Removal and Installation
        Inspection
        Leak Test with Compressed Air
        Leak Test with a Radiator Cap Tester
        Inspection for Radiator Clogging
        Cleaning the radiator inside
        Cleaning with a detergent
        Cleaning radiator exterior
        Cleaning radiator cores
        Visual Inspection of the Exterior Parts
        Radiator Cap Inspection
        Function Test
        Assembly
        Filling and Draining
        Daily Inspection
        Coolant level inspection and coolant replacement
        Antifreeze
        Precaution for Filling Antifreeze
        Radiator Hose
      - Fan Belt
        Removal and Installation
      - Water Pump
        Removal and Installation
        Overhaul
        Impeller and Seal Unit
      - Thermostat
        Removal and Installation
        Operating Test
      - Troubleshooting
    - Air Cleaning System
      - General Description
      - Engine air cleaner
        Servicing
    - Fuel System
      - General Description
        Fuel Filter
        Air-Bleeding Fuel System
        Fuel Pump
        Fuel Tank Filler Cap
        Throttle Lever
    - Index

04 – Engine

04 – Engine
- ST55 Tractor Service Manual
  - 04 Engine
    - General Information and Specifications
      - Introduction
      - Specifications
    - Service Standards
      - Precautions for Service Operation
      - Preparation for Operation
      - Precautions During Operation
      - Service Standards Chart
        Tightening Torque Table
        Troubleshooting
      - Keys to Inspection and Servicing Engine
        Operational Precautions for New Engines
        Inspection and Preparation
        Engine Oil
        Fan Belt Tension
        Fuel
        Coolant
        Engine Starting
        Operation
        Oil Pressure
        Coolant Temperature
        Battery Charging
        Stopping
        Long Term Storage
        Air Bleeding
        Periodical Inspection
        Changing Engine Oil
        Changing Oil Filter Cartridge
      - Inspection and Service of Main Components
        Cylinder Head
        Combustion Process
        Valve Seat
        Valve Guide
        Valves
        Valve Head Thickness
        Valve Springs
        Cylinder Head
        Rocker Arm Shaft Assembly
        Breather
        Cylinder Head Gasket
        Cylinders, Pistons And Connecting Rods
        Cylinder Block
        Pistons and Connecting Rods
        Crankshaft
        Intake & Exhaust Valve Mechanism
        Valve Operation
        Valve Timing
        Tuning Valve Timing
        Valve Clearance
        Adjusting Valve Clearance
        Inspecting Camshaft
    - Disassembly and Assembly
      - Disassembly
        Draining of Engine Oil
        Removal of Fan Belt
        Removal of Solenoid, Alternator and Starter
        Removal of Intake and Exhaust Manifolds
        Removal of Cylinder Head Cover
        Removal of Injection Nozzles and Related Parts
        Removal of the Crankshaft Pulley and Water Pump
        Removal of Cylinder Head
        Removal of Gear Case
        Removal of Injection Pump
        Removal of Gears and Front Plate
        Removal of Flywheel and Rear Plate
        Removal of Oil Pan and Strainer
        Removal of Connecting Rods and Pistons
        Removal of Crankshaft
      - Assembly
        Installation of Crankshaft
        Installation of Pistons and Connecting Rods
        Installation of Strainer and Oil Pan
        Installation of Rear Plate and Flywheel
        Installation of Front Plate and Gears
        Installation of the Injection Pump
        Install the Gear Case
        Installation of Crankshaft Pulley and Water Pump
        Installation of Cylinder Head
        Installation of Nozzles and Related Parts
        Installation of Cylinder Head Cover
        Installation of Intake and Exhaust Manifolds
        Installation of Injection Piping
        Installation of Solenoid and Alternator
        Installation of Cooling Fan
    - Lubrication
      - Lubrication System
        Lubrication Diagram
        Oil Pump
        Specifications
        Oil Filter
        Specifications
        Construction and Operation
        Relief Valve
    - Cooling System
      - Coolant System
        Water Pump
        Specifications
        Thermostat
        Specifications
        Construction and Operation
        Adjustment of Fan Belt
        Anti-Freeze
    - Fuel System
      - Fuel System Diagram
        Injection Pump
        Construction
        Basic Operation
        Details of Construction
        Construction and Operation of Delivery Valve
        Injection Pump Timing
        Precautions
        Adjusting Method of Fuel Injection Timing
        CTD Pump
        Construction
        Functions
        Removal, Disassembly, Inspection, Assembly, and Installation
        Removal Of Injection Pump
        Disassembly Of Injection Pump
        Inspection Of Injection Pump
        Assembly Of Injection Pump
        Adjustment Of Injection Volume And Adjustment Conditions
        Nozzle And Nozzle Holder
        Precautions
        Inspection by Sight
        Test for Smooth Movement of Needle Valve
        New Nozzle Installation
        Governor
        Operation Principle
        Governor Operation
        Function of Adapter (Angleichung) Unit
        Angleichung Function at Low Speed Under Full Load
        Features of the Governor on This Engine
    - Alternator
      - Specifications And Construction
      - Removal, Disassembly, and Assembly
        Removal
        Disassembly
        Inspection
        Assembly
      - Troubleshooting
    - Glow Plugs
      - Construction and Operation
        Specifications
      - Inspection
    - Engine Shut-Off Solenoid
      - General Information
        Specifications
    - Tachometer
      - Tachometer Speed Pick-Up
    - Starter
      - Construction
      - Removal, Inspection, and Installation
        Removal of Starter
        Inspection Of Components
        Assembly of Starter
        Inspection of the Starter After Removal from the Tractor
        Performance Test
        Installation of Starter
        Other Information
        Service Standards
    - Index

05 – Clutch

05 – Clutch
- ST55 Tractor Service Manual
  - 05 Clutch
    - General
      - General Description
    - Specifications
    - Main Clutch
      - Removal and Installation
      - Overhaul
      - Inspection
      - Inspection of Pressure Plate
      - Adjustment of Pressure Springs
      - Inspection of Pressure Springs
      - Inspection of Other Parts
      - Assembly
    - Clutch Cross Shaft
      - Clutch Cross Shaft and Related Parts
        Removal and Installation
        Disassembly
        Inspection
        Assembly
    - Clutch Pedal and Linkage
      - Clutch Pedal Free-Play
        Adjustment
      - Clutch Rod Linkage
        Removal and Installation
    - Troubleshooting
    - Index

06 – Transmission

06 – Transmission
- ST55 Tractor Service Manual
  - 06 Transmission
    - General Information
      - General Description
        Wheel Driving System
        Ground Speed Selection (4WD Model)
        Ground Speed Selection (2WD Model)
        PTO Drive System
      - Specifications
        Wheel Drive System
        PTO Drive System
    - Power Flow Diagrams
      - Speed Shift Patterns and Gear Train Diagrams
    - Input Gears
      - Construction
      - PTO Clutch
      - Oil Supply to Clutch Packs
      - Specified Tightening Torques of Pipe Joints
      - Location of Reducing Valve and Piping
      - Reducing Valve Operation
    - PTO Solenoid
      - Operation of PTO Solenoid
    - Timer Unit
      - Control of Timer Unit
      - Location of PTO Timer Relay
    - PTO Clutch
      - Overhaul
      - Disassembly
      - Inspection
      - Disc Assembly
      - Driven Plate
      - Brake Disc
      - Assembly
    - Shuttle System
      - Mechanical Shuttle Clutch Pack
        General
      - Forward / Reverse Shuttle Synchronizer
        Function Principles (Operating Procedures)
        First Stage
        Second Stage
        Third Stage
        Fourth Stage
      - Forward Reverse Shift Linkage
        Removal and Installation
        Assembly
      - Shuttle Cable
        Removal and Installation
    - Input and Output Gears
      - Input Housing and Gears
        Removal and Installation
        Installation of Input Shaft and Related Parts
      - Main Change Gears Shift and 4WD
        Main Transmission Gears
        Disassembly of Main Change Gears
        Inspection
        Assembly
        Main Transmission Shift Linkage
      - Range Change Gears
        Removal and Installation
        Overhaul
        Overhaul
      - Rear Differential
      - Ring Gear and Pinion
        Removal and Installation
        Overhaul
        Inspection
        Assembly
      - Inspection of Tooth Contact
        Correct Contact
        Assembly Information
      - PTO Shaft and Related Parts
        Removal and Installation
        Disassembly
        Assembly
        Disassembly
        PTO Shift Linkage
      - Frontwheel Drive Gears
        Removal and Installation
        Disassembly
        Assembly
    - Troubleshooting
      - Wheel Drive System
      - PTO Drive System
    - Index

07 – Front Axle

07 – Front Axle
- ST55 Tractor Service Manual
  - 07 Front Axle
    - General Information
      - General Description
      - Specifications
    - Front Wheel Drive Shaft
      - Front Wheel Drive Shaft (4WD)
        Removal and Installation
    - Pivot Bracket Bushing
      - Removal and Installation
        Disassembly
        Inspection
        Inspection – Bevel Gear Housing Shaft Diameter
        Inspection – Bevel Case Bushing Bore
        Inspection – Front Axle Shaft Diameter
        Inspection – Front Axle Bushing Bore Diameter
        Assembly
    - Front Differential
      - Components
        Removal and Installation Pinion Carrier Assembly
        Disassembly
        Overhaul
        Inspection
        Assembly
        Disassembly Differential Gears
        Inspection
    - Final Drive and Wheel Shaft
      - Final Drive – Wheel
      - Wheel Shaft Seal or Cover
        Removal and Installation
    - Final Drive Housing
      - Overhaul
        Inpsection Prior to Disassembly of Drive Housing
        Disassembly
      - Inspection
        Bearing Cover Shaft
        Drag Arm Bushing Bore Diameter
        Final Housing Shaft Diameter
        Final Housing Bushing Bore Diameter
        Assembly
        Tie Rod System (4WD)
      - Front Axle (2WD)
      - Axle Removal and Installation
        Removal
        Installation
        Front and Rear Endplay Adjustment
        Inspection
    - Knuckle Spindle
      - Removal
      - Installation of the Knuckle Spindle
      - Inspection
    - Front Wheel Hub
      - Removal
      - Installation
    - Troubleshooting
      - Tire Inflation Pressures
      - Wheel Bolt Torque
      - Front Wheel Alignment
        Toe in Adjustment – 4WD
        Toe in Adjustment – 2WD
      - Wheel Spacing
      - Steering Free-Play
    - Index

08 – Rear Axle

08 – Rear Axle
- ST55 Tractor Service Manual
  - 08 Rear Axle
    - General Information
      - General Description
      - Specifications
    - Brakes
      - Final Drive Gear
        Removal and Installation
      - Axle / Axle Seal or Bearing (One Side)
        Removal and Installation
      - Brake Disc
        Removal and Installation
      - Brake Overhaul
      - Inspection
        Friction Plates
        Actuator
        Separator Plate
        Assembly
      - Differential Lock Clutch
        Removal and Installation
      - Rear Axle Housing (One) Replace
      - Brake Boot (One)
        Removal and Installation
      - Brake Adjustment
      - Brake Rod (One)
        Removal and Installation
      - Brake Pedal (One)
        Removal and Installation
      - Parking Brake
        Removal and Installation
      - Rear Axle Assembly Guidelines
    - Troubleshooting
    - Index

09 – Power Steering System

09 – Power Steering System
- ST55 Tractor Service Manual
  - 09 Power Steering
    - Construction
    - Steering Orbital
      - Components
    - Disassembly and Assembly
      - Disassembly
        Disassembly of Rotor Side
        Disassembly of Control Side
        Inspection
      - Assembly
        Assembly of Control Side
        Assembly of Gerotor Side
        Steering Free Play
    - Troubleshooting
    - Index

10 – Hydraulics

10 – Hydraulics
- ST55 Tractor Service Manual
  - 10 Hydraulics
    - General Information
      - General Description
      - Specifications
      - Transmission Oil (Hydraulic Oil) Replace
      - Transmission Cartridge Filter (Includes Oil Change)
        Removal and Installation
        Bleeding Air
    - Hydraulic Pump
      - General
      - Hydraulic Pumps
      - Removal and Installation
      - Disassembly
      - Inspection and Repair
      - Pump Gears
      - O-rings
      - Oil Seal
      - Assembly
      - Inspection After Assembly
      - Hydraulic Lift Housing
      - Lift Shaft and Crank
        Removal and Installation
        Assembly
      - Hydraulic Cylinder and Piston
        Removal and Installation
        Hydraulic Linkage System Adjustment
        Position Control Adjustment
        Step 1
        Step 2
        Step 3
        Step 4
        Step 5
        Step 6
        Step 7
        Summary of Position Control Adjustments
    - Hydraulic Valves
      - Main THREE-POINT Control Valve
        General Description
        Specifications
        Main Spool
        Unloading Valve (Compensator)
        Unloading Valve
        Holding Check Valve
        Pilot Spool
      - Operation
        Neutral Position
        Lifting Position
        Lowering Position
        Lifting to Neutral to Shifting (Unloading Process)
      - Control Valve
        Removal and Installation
        Overhaul Tightening Torque
      - Disassembly
        Main Spool and Related Parts
        Holding Check Valve B and Related Parts
        Unloading Valve C (Compensator)
        Unloading Valve D
        Pilot Spool E and Related Parts
      - Assembly
        Inspection of Disassembled Parts
        Main Spool A and Related Parts
        Holding Check Valve B and Related Parts
        Unloading Valve C (Compensator) and Related Parts
        Unloading Valve D and Related Parts
        Pilot Spool E and Related Parts
      - Main Relief Valve
        General Description
        Removal and Installation
        Overhaul
        Pressure Check Main Relief
      - Relief Valve (SAFETY VALVE)
        General Description
        Operations
        Removal and Installation
      - Flow Control Valve (Slow Return Check Valve)
        General Description
        Control Valve Detail
        Down Position
      - Slow Lowering Check Valve
        Removal and Installation
    - Hydraulic Cylinder
      - Hydraulic Cylinder Cover
        Replace
      - Piston Lift Rod
        Removal and Installation
      - Remote Hydraulic Control (Optional)
        General Description / Functions
      - Remote Hydraulic Control Valve
        Specifications
      - Oil Flow (Single/Double) Action
      - Switch Between Single Acting and Double Acting
      - Remote Hydraulic Control Ports
      - Remote Control Valve (Accessories)
        Removal and Installation
        Overhaul
    - Troubleshooting
    - Index

11 – Electrical

11 – Electrical
- ST55 Tractor Service Manual
  - 11 Electrical
    - General Information
      - Electrical Formulas
      - General
      - Specifications
    - Battery
      - Removal and Installation
      - Inspection
        Inspection of Electrolyte Level
        Inspection of Electrolyte Specific Gravity
        Temperature Correction of the Hydrometer Reading
        Battery Charging
    - Instrument Panel and Sensors
      - Instrument Panel
        Removal and Installation
      - Tachometer
        Removal and Installation
        Inspection
      - Fuel Gauge and Sensor
        Fuel Gauge and Sensor Testing
        Gauge Checking
        Sensor Checking
      - Fuel Gauge
        Removal and installation
      - Fuel Sensor
        Removal and Installation
      - Coolant Temperature Gauge
        Removal and Installation
      - Coolant Sensor
        Removal and Installation
      - Start Switch
        Removal and Installation
        Inspection
      - Light Turn Signal
        Removal
        Inspection
      - Safety Switch and PTO safety Relay
        Neutral Start Switch Caps
      - PTO Safety – Relay
        Removal and Installation
      - PTO Switch
        Removal and Installation
    - Engine
      - Engine Shut Off Solenoid
        Removal, Installation and Testing
      - Wiring Harness
        Removal and Installation
        Electrical
        Battery
      - Front Light Bulbs
        Removal and Installation
      - Signal Light / Tail Light Bulbs
        Removal and Installation
      - Instrument Light Bulbs
        Removal and Installation
        Indicator Light Strip
      - Glow Plugs
        General
        Specifications
        Construction
        Circuit – Testing
        Quick Check
        Glow Indicator Checks
      - Glow Plug Indicator
        Replace
      - Engine Glow Plugs
        Replace
        Main Fuse Box A
        Slow-Blow Fuses B and C
        Trailer Harness Connector D
        Rear Work Light Connectors E
        Unused Wire leads F
    - Troubleshooting
      - Lighting System
      - Instrumentation
      - Glow System
    - Index

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