Allis Chalmers Crawler Hd21a Parts Manual

Allis Chalmers

Allis Chalmers Crawler Tractor Hd21a Sn 12801 Up Parts Manual

HD21A Service Manual – Table of Contents

1. General Information / Chassis

• Safety Instructions
• Machine Overview and Specifications
• Identification and Serial Number Locations
• Chassis Structure and Description

2. Engine Assembly

• Cylinder Block
• Cylinder Head
• Crankshaft and Bearings
• Pistons, Rings, and Connecting Rods
• Camshaft and Valve Mechanism

3. Fuel System

• Fuel Tank
• Fuel Lines
• Fuel Filters
• Fuel Injectors and Injection Pump

4. Lubricating System

• Oil Pump
• Oil Cooler
• Lubrication Filters
• Oil Lines and Fittings

5. Cooling System

• Radiator
• Cooling Fan and Belts
• Water Pump
• Thermostat and Coolant Passages

6. Air Intake & Exhaust System

• Air Cleaner
• Turbocharger (if equipped)
• Intake Manifold
• Exhaust Manifold and Muffler

7. Engine Clutch and Torque Converter

• Engine Clutch Assembly
• Torque Converter Description and Servicing

8. Transmission

• Transmission Case and Gears
• Gear Shift Linkage
• Transmission Servicing Procedures

9. Bevel Gear

• Bevel Gear Inspection and Adjustment
• Gear Housing Components

10. Steering Clutches & Controls

• Steering Clutch Operation
• Control Linkages
• Disassembly and Adjustment

11. Final Drives

• Final Drive Gears and Bearings
• Housings and Seals
• Lubrication Procedures

12. Truck Frames / Track Frames

• Structural Overview
• Mounting Points and Alignment

13. Tracks

• Track Shoes
• Pins and Bushings
• Track Chain Maintenance

14. Track Idlers & Rollers

• Track Idlers
• Carrier (Support) Rollers
• Truck Wheels (Bottom Rollers)
• Drive Sprockets

15. Main Frame & Equalizing Spring

• Frame Layout and Maintenance
• Equalizer Spring Inspection and Adjustment

16. Drawbar

• Drawbar Assembly and Mounting
• Wear and Alignment Checks

17. Brake System

• Brake Pedal and Linkage
• Brake Bands or Discs
• Hydraulic or Mechanical Brake Components

18. Steering System

• Steering Wheel and Columns
• Hydraulic Steering Components (if equipped)
• Mechanical Linkages

19. Hydraulic System

• Working Hydraulics
• Hydraulic Pumps and Control Valves
• Reservoirs, Filters, and Cylinders

20. Electrical System

• Battery and Cables
• Alternator and Charging System
• Starter Motor
• Wiring Harness and Connectors
• Lighting and Instrumentation

21. Operator’s Compartment

• Cab Structure (if applicable)
• Operator Seat and Controls
• Fenders and Floor Panels

22. Guards

• Crankcase Guard
• Radiator Guard
• Miscellaneous Shields and Covers

23. Attachments / Special Equipment

• Dozer Blade Components
• Rippers and Mounting Brackets
• Auxiliary Hydraulic Attachments