The Cummins N14 is a popular diesel engine prevalently installed in commercial trucks, RVs and agricultural and construction equipment. Built on a basic 855 cubic inch Cummins engine, the N14 was produced from the late 1980s until 2000, when it was discontinued and replaced with the ISX line of engines. The N14 received some slight updates throughout its production years, but remained the same at its core.
The Cummins N14 is capable of producing between 310 and 525 horsepower, depending on the size of the turbo chosen by the vehicle manufacturer. It is also capable of generating 1,250 to 1,850 foot-pounds of torque at 1,200 RPM. As an OEM engine provider to vehicle manufacturers, Cummins offers a large number of turbo setups equipped for the diesel-powered N14 engine. The amount of engine power needed out of the N14 is typically dictated by the purpose of the vehicle that's receiving the N14 engine.
EPA and Fuel Updates
To conform to regulatory changes made by the Environmental Protection Agency, Cummins had to slightly change the N14's fuel system in the early 1990s. Cummins took this opportunity to brand its modified fuel system "Celect." It utilised an electronic control module to regulate the amount of fuel delivered to the new electronic fuel injectors.
The N14 engine's ignition fires off its cylinders in the order of 1, 5, 3, 6, 2, 4. It has an intake valve clearance of 0.014 inches and an exhaust valve clearance of 0.027 inches. Its engine brake clearance is 0.023 inches. The N14's operating oil pressure at idle is 4.54 Kilogram per square inch, rising to 11.3 Kilogram per square inch at 1,200 RPM. When cranking, the engine's operating fuel pressure is 11.3 Kilogram per square inch and 54.4 Kilogram per square inch at 1,200 RPM.