Written By, Mike McGlothlin
Cummins N14
History
Cummins introduced the N14 in 1987 to replace the 855 Big Cam. As part of Cummins N14 history, the engine incorporated, a fair share of revisions into its design, it shares the same block, oil pan, bore, stroke, and modular (4-valve) cylinder heads with its predecessor. The cast-iron block and head N14 features a 5.50-inch bore and a 6.00-inch stroke to arrive at its 855 cubic inch (14.0L) displacement. Early N14’s produced from 1987 to 1989 are fully mechanical (no ECM) and make use of a Pressure-Time (“PT”) injection system. However, beginning in 1990 the CELECT acronym entered the picture, which stood for Cummins Electronic Engine Control, and brought precise fuel metering and unit injection into the fold. These early design elements remain a major part of Cummins N14 specs.
Common Applications
In road-going vehicles, the Cummins N14 engine was a hit in the Class 7 and 8 truck segments, where they often powered semitrucks and multi-axle dump trucks. The N14 was also offered in fire trucks and emergency equipment, as well as luxury motor coaches. In off-road applications, the N14 earns its keep in heavy tillage farm tractors, wheel loaders, excavators, and gen-sets, but is also widely used in industrial applications such as compressors, pumps, and G-drives. Marine vessels such as tugboats, commercial fishing boats, work boats, and pleasure craft also benefit from N14 propulsion. Power ratings range from 310 hp to 525 hp, and 1,250 lb-ft to 1,850 lb-ft of torque.
Production Run
Cummins N14 was produced from 1987 to 2002, and in that time three distinct versions were manufactured: the N14, N14 CELECT, and N14 CELECT Plus. Unlike the ISX series that would follow it, and be built at a single location, the N14 was produced at various plants globally. Columbus, Indiana, Japan, China, Indian, Mexico, and Brazil were among the production locations, in one capacity or another. The N14’s reputation for durability and above-average fuel efficiency (especially in over-the-road Class 8 applications) drove demand, allowing it to compete with other highly popular engines of the day, including CAT’s 3406E and Detroit Diesel’s Series 60. This long production timeline is a key part of Cummins N14 history.
Still Remembered, Still In Demand
The Cummins N14 engine might developed a few leaks with age (what diesel engine doesn’t?), but it is a highly durable workhorse. With the N14, the question is never “if” the engine would go a million miles or not, but “how far” beyond 1 million miles it will go. Combine durability with ample power output and then sprinkle in high fuel efficiency and you can see why many veteran truck drivers consider the N14 the best engine they’ve ever operated. And this is exactly why the engine is still well supported today. Replacement parts and rebuildable cores can still be sourced with relative ease, and Cummins even manufactures ECM upfit kits for customers with failed or failing original ECM’s.
Sources:
Big Bear Engine Company
https://www.4btengines.com/cummins-n14-engine/
CM876 Upfit ECM Kit
https://mart.cummins.com/imagelibrary/Asset/5600659_0325.pdf.ashx
https://www.capitalremanexchange.com/cummins-n14-specs-history-problems/
N14 History and Specs Corroboration
