The Challenger name has become synonymous with performance, versatility and reliable power in the agricultural tractor market. So, customers shouldn't expect anything less from a new series of Challenger Endurance diesel engines, which are among the exciting and innovative features found on the redesigned MT600B Series tractors.

“The first two models to premiere under the Challenger brand name are an Endurance 74ETA 7.4 liter (451 cu. in.) diesel, which is used in the 180-hp MT635B and 200-hp MT645B, and the Endurance 84ETA 8.4 liter (512 cu. in.) unit, which showcases in the 220-hp MT655B and the 240-hp MT665B.” said Adrian Crisp, general marketing manager for Challenger high-horsepower wheel tractors. “Both six-cylinder models feature an electronic engine management (EEM) system that works in perfect harmony with the Bosch electronic fuel injector to provide quick and precise response to throttle movement.”

Constant communication

The EEM system is also in constant communication with the MT600B Series' standard-equipment TechStar CVT (Continuously Variable Transmission) to maintain a consistent ground speed, regardless of engine speed or vice versa. EEM input allows the operator to program or recall two specific engine speeds with the touch of a button on the right-hand console. A second switch permits engine speeds to be adjusted in increments of 10 rpm independent of hand throttle position.

Boast unique features

According to Barry O'Shea, sales engineer for Challenger tractors, Endurance engines also boast unique features that provide up to 12 percent more PTO horsepower and up to 40 percent torque backup. Both models feature a turbocharger and aftercooler, as well as four valves per cylinder for exceptional power and efficiency across a wide range of applications.

Built exclusively for Challenger by Sisu Diesel, a wholly owned division of AGCO Corporation, Endurance engines are based on a single-piece cast-iron block that provides maximum strength and durability. Wet cylinder liners and charge air-cooling combine for more effective cooling at the top of the cylinder. Unlike most sleeved cylinder engines, however, Challenger Endurance models feature mid-support of the cylinder liners to reduce vibration by up to 75 percent. This, in turn, reduces overall engine wear and noise.

Other innovations

Other design innovations include piston connecting rods that are individually balanced for smoother operation and longer life, and a circular head bolt pattern, for greater strength around the top of each cylinder. Each Challenger engine is even assembled by one person, whose name is recorded on the serial number plate — providing customers with the ultimate in quality assurance.

“Most importantly, these aren't any off-the-shelf diesel engines adapted for use in a tractor,” O'Shea insisted. “Sisu has more than 50 years of experience in the development and production of rugged agricultural equipment engines. Plus, these engines were designed and tested in partnership with Challenger engineers to insure the highest level of performance and longevity in combination with features like the TechStar CVT and the new Power Performance III software.”