Bobcat 843, 843B Skid-Steer Loader Repair Manual

The Bobcat 843 and 843B skid-steer loaders were produced from 1985 through 1992 and remain widely respected for their robust design, versatile performance, and ease of maintenance. Powered by either Isuzu or Perkins 4-cylinder liquid-cooled diesel engines producing 54 horsepower, these loaders deliver a rated operating capacity of 1,700 lbs with a tipping load of 3,420 lbs, making them ideal for a wide range of construction, agricultural, and industrial applications.

With an operating weight of 6,480 lbs, the Bobcat 843 / 843B combines stability with maneuverability, featuring a standard 60-inch bucket capable of holding up to 11.5 cubic feet of material. The auxiliary hydraulics provide a high-flow output of 16.1 gallons per minute, ensuring compatibility with demanding attachments.

Maintenance & Safety

This comprehensive manual begins with a thorough MAINTENANCE SAFETY section, emphasizing best practices for preventing accidents during repairs, followed by detailed FIRE PREVENTION guidance, SERIAL NUMBER LOCATIONS, and proper identification of loader and engine serial numbers for accurate service and parts ordering.

Preventive Maintenance

The PREVENTIVE MAINTENANCE chapters provide illustrated procedures covering:

• Service schedules for routine checks,

• Proper methods for lifting and blocking the loader,

• Transportation guidelines,

• The use of critical safety features such as the lift arm stop,

• Operator cab maintenance, including inspection and servicing of the seat bar system.

These sections also include step-by-step instructions for jump-starting using an external battery and using a remote start switch safely.

Hydraulic & Hydrostatic Systems

The HYDRAULIC SYSTEM and HYDROSTATIC SYSTEM sections cover in-depth schematics, troubleshooting charts, and detailed component-level service instructions for lift and tilt cylinders, control valves (Cessna and Melroe), hydraulic pumps, pedal assemblies, and hydrostatic motors and pumps. Procedures include removal, disassembly, inspection, and reassembly, providing technicians with everything needed to fully overhaul these systems.

Drive, Frame, & Electrical Systems

Coverage continues with the DRIVE SYSTEM, including parking brake adjustments, axle service, final drive chains, and the reduction gearcase. The MAIN FRAME section addresses removal and installation of the operator cab, lift arms, Bob-Tach system, rear door, and fuel tank variations based on serial number.

The ELECTRICAL SYSTEM details schematics, diagnostics, and comprehensive repair procedures for the battery, alternators (Melroe and Mando), and starter, along with checks for regulators, wiring, and adjustment of electrical components.

Engine Service

Three engine-specific service sections are included:

• Perkins Engine,

• Perkins 200 Series Engine, and

• Isuzu Engine,
  each providing exhaustive coverage from troubleshooting and valve adjustments to full teardown and rebuild procedures. Topics range from compression tests, fuel system bleeding, timing the injection pump, cylinder head and valve work, pistons and liners, to crankshaft and camshaft service.

Technical Data & Specifications

The TECHNICAL DATA chapters conclude the manual with torque specifications, hydraulic fluid specs, conversion charts, and complete engine technical data for all supported engine configurations. Specifications such as 54 hp power output, 1,700 lb rated capacity, 131.4 in overall length, 62.4 in width, 80.4 in cab height, and 119.6 in bucket hinge pin height give a complete picture of the machine’s capabilities.

Manual Revisions

Finally, the manual includes a SERVICE MANUAL REVISIONS section, documenting updates from 843-1 through 843-17, ensuring technicians always have the most current service information.

This manual is essential for owners, operators, and technicians servicing the Bobcat 843 and 843B, providing detailed instructions and specifications for maintaining peak performance and reliability.