Only 16 months ago, JCB began manufacturing its own 4.4-liter diesel engine at its new Dove Valley factory in Derbyshire, England, where production now stands at 100 units per day. At present, the new engine, Model 444, is used in more than half of the company's 220 different machines. According to JCB, the 444-engine project represents the largest single investment made by the company in its 60-year history — an estimated $140 million. The new engine was five years in development, says JCB, which included 100,000 hours of testing before its launch.
The production process at the Dove Valley facility, in fact, was developed simultaneously with the engine and is based on a "no faults forward" philosophy. This means, says JCB, that computerized control systems in the highly automated factory prevent an engine from moving to the next production station if a missing part or defective process is detected. In addition, every engine is "hot-tested" before shipment.
The design of the four-cylinder, four-valves-per-cylinder 444 is based on a 1.1-liter (67-cubic-inch) displacement per cylinder, with a bore of 103 millimeters (4 inches) and a stroke of 132 millimeters (5.2 inches). The performance range of the new engine includes 74- and 84-hp naturally aspirated versions, up to 100 horsepower in turbocharged trim, and 125 horsepower when a charge-air cooler is used with the turbo. Peak torque at 1,300 rpm is, respectively, 320, 425 and 525 Newton meters (236, 314 and 387 pounds-feet).
According to JCB, major design targets for the 444 included robust construction, high torque at low speeds, reduced sound levels and a basic architecture that would facilitate the next steps in emissions regulations. The 444, says JCB, uses a large crankshaft and an exceptionally stiff cylinder block, which is mated to a cast-iron "bedplate" that encloses the bottom of the block and accommodates the bottom half of the main bearings. The engine's structural stiffness reduces radiated noise, says the company, and the engine has an overall sound level of 89 dB(A) at one meter's distance at full load, and 78 dB(A) at idle. Further sound reduction results from rear-mounted timing gears and a specially designed oil pan.
Partners in the 444's development included Ricardo Consulting Engineers, AVL for combustion and emissions, and Cosworth (now Mahle Powertrain) for block and head machining. In due course, says JCB, an anticipated 20 percent of the 444's production may be marketed to third parties.