Ford 550/555 Tractor Backhoe Loader Service Manual (P/N C4077-90960)

• Covers the 1975–1981 Ford 550 and 555 tractor-loader-backhoe models, documenting both diesel and gasoline engine configurations
• Official Ford Tractor Operations publication P/N C4077-90960
• Contains 97 pages of technical specifications, exploded-view diagrams, and specialized tooling requirements
• Serves as the foundational reference detailing engine, cooling, and fuel injection systems for the entire production run

Engine System and Fuel Documentation

This publication provides the factory technical data required for engine overhaul and routine maintenance. It outlines exact procedures for cylinder head disassembly, valve train inspection, and piston ring replacement. You will find exploded views illustrating component orientation, which removes the guesswork during reassembly in the shop. The documentation breaks down the lubrication system, detailing rotor-type oil pump function and main gallery oil flow. It also covers cooling system service, notably addressing the water pump assembly modifications implemented for units built after March 23, 1981.

Specification Highlights

Having the exact numbers on hand is critical for heavy equipment repair. This reference documents engine specifications for both fuel types, listing compression ratios, bore and stroke dimensions, and precise assembly torque sequences. For fuel system work, it provides detailed injector testing parameters, including nozzle opening pressure and spray pattern verification.

Rated torque for main bearing bolts is set at 115–125 lb-ft (156–159 Nm). Diesel compression pressure must read 340 ± 50 psi at 200 rpm. Valve stem-to-guide clearance for intake valves is specified at 0.0010–0.0027 in (0.025–0.069 mm). The manual emphasizes these specific factory tolerances and safety protocols that must be strictly maintained during equipment servicing to prevent component failure and ensure workplace safety.