Cummins N14 Engine Shop Manual, 1991 (P/N 3810487)

• Applies to 1991 Cummins N14 Diesel Engines, including CELECT and STC fuel systems.
• Official OEM publication Bulletin No. 3810487, printed February 1991.
• Features over 100 exploded-view diagrams, precise torque value tables, and component maintenance specs across 587 pages.
• Remains the definitive reference for the N14 engine launch build, delivering essential rebuild data for the cylinder block, head, and fuel network.

Component Teardown and Rebuild

This manual outlines the exact factory workflows for engine disassembly, cleaning, and assembly. It breaks down all 22 major component groups, from the cylinder block and crankshaft up to the fuel injectors and turbochargers. The guide provides specific torque sequences for every major fastener and highlights exactly which service tools you need—like the ST-125 lifting fixture and specialized torque wrench adapters. Because heavy-duty diesel service involves substantial weight and high pressures, always ensure you are properly equipped or consulting a certified technician before performing these procedures to avoid component damage or personal injury.

Engine Specifications and Factory Tolerances

Get the exact technical data required to restore peak performance. The publication documents critical tolerances, including cylinder liner protrusion measurements and crankshaft end clearance limits. You will find complete torque tables, such as the final-stage 346 N.m [255 ft-lb] for main bearing caps and the multi-stage 90-degree rotations for cylinder head bolts. Intake valve clearances are clearly detailed in the timing section, giving you the exact layout and depth expected when utilizing OEM service publications for major overhauls.