1978 John Deere JD300-B Loader & Backhoe Technical Service Manual TM-1087

Technical Scope for the 1978–1979 John Deere JD300-B Loader and Backhoe

• Built for service technicians and workshop environments maintaining the 1978–1979 John Deere JD300-B Loader and Backhoe
• Official John Deere publication TM-1087, revision dated December 1978
• Contains 47 exploded-view diagrams, 16 maintenance and adjustment charts, and 4 specialized torque-specification tables
• Accessible from your device as soon as the order is placed
• Suitable for printing individual sections for shop-floor use
• Indexed PDF search covers every chapter and appendix
• Full-text search finds any part number in seconds
• This 1978 technical manual is the primary reference for the JD300-B build, detailing system diagnostics and disassembly for the 3-cylinder diesel engine, hydraulic backhoe controls, and mechanical power train

Engine and Hydraulic System Documentation

This manual provides a detailed technical overview of the John Deere JD300-B machine. The documentation covers the mechanical engine, including the cylinder head, valve train, and timing gear train assembly. The manual also outlines the hydraulic system operation, covering the transmission-hydraulic pump, steering valve, and brake valve components. Each section provides system diagnostic tests, ensuring accurate identification of operating issues through visual inspections and measured pressure checks. The service information assists in teardown and reassembly processes, including specific torque values for engine fasteners and hardware.

Specification Highlights

The 1978–1979 John Deere JD300-B technical data preview includes critical operating parameters and wear limits. Cylinder head bolt torque is specified at 95 lb-ft in the engine assembly data. The maximum hydraulic system operating pressure is documented at 2350 psi in the hydraulic system specification chart. Main bearing bore I.D. for the John Deere JD300-B is specified at 3.3250 to 3.3260 inches in the basic engine service tables. All service data shown here is for reference only — qualified technicians and the original OEM documentation remain the authoritative source for any hands-on work.

This 596-page technical manual provides factory-authorized specifications for the 1978–1979 John Deere JD300-B, covering the engine, power train, electrical, and hydraulic systems required for maintenance and repair of this specific loader and backhoe model.