Kohler launches the KDI 3404, its largest diesel engine yet

Updated Feb 10, 2015
Jeff Wilke, product manager for diesel engines in North America, with the KDI 3404 at World of Concrete.Jeff Wilke, product manager for diesel engines in North America, with the KDI 3404 at World of Concrete.

To serve the needs of customers who want high-power density engines in a compact envelope, Kohler unveiled it’s latest, and biggest engine yet at the World of Concrete show Tuesday. The KDI 3404 is a 3.4 liter, four cylinder engine that cranks out 134 horsepower and 276 to 369 foot pounds of torque.

The engine is compact for it’s displacement and power, says Jeff Wilke, product manager for diesel engines in North America. “We were able to replace larger displacement engines with the power density we offer. Power density is 30 kW (40.2 horsepower) per liter.”

The 3404 joins two smaller units, a 2.5 liter and 1.9 liter in the KDI family. All three have the distinction of not having to use a DPF for emissions control. The models above 75 horsepower will use Selective Catalytic Reduction to lower emissions. Below 75 horsepower, cooled EGR is the primary emissions technology.

Kohler will build two versions of the 3404 engine in its plant in Italy. A fully electronic version will be sold in emissions restricted countries in North America, Europe and Japan. A mechanical injection model will go to countries that don’t have emissions regulations. The mechanical models can also run on high-sulfur fuel in common in non-regulated countries.

Fuel is delivered in a 2000 bar (29,000 psi) high-pressure common rail fuel system. Injectors are located in the center of the cylinders. Four valves per cylinder control the movement of fuel and exhaust.

The block was designed to enhance cooling and honed in a proprietary process. That keeps the cylinders from distorting and keeps the oil from leaking past the rings and further enhances emissions reductions. This and the cleaner burning design helps extend oil drain intervals out to 500 hours.

Some added features with the 3.4 liter designs include and A-mount and B-mount PTO configurations (one on each side of the engine), large bearings for long life and large applications. Counterbalancing is available for applications that require a smoother running engine.