Hands-on engine technology with Kohler

2023 is an important milestone for Kohler Co. as the company is celebrating its 150th anniversary. As part of the celebrations, Kohler Engines hosted its first Demo Days at the headquarters in Reggio Emilia, Italy.

The event was meant for trade press and aimed at presenting actual applications for the company’s range of engines and hybrid solutions, with a chance to see the machines in operation and even try them firsthand.

The first Kohler Demo Days were hosted at the test track of Kohler Engines’ headquarter in Reggio Emilia, Italy

The event showed the variety of applications Kohler can cover with its gasoline engines, the diesel units and the most recent electric-diesel hybrid solutions.

Kohler Engines’ Director of Marketing Communications & Channel Management, Nino De Giglio, opened the event with some comments about the company’s important milestone and the philosophy that encompasses the whole group, centered on the mission of contributing to ‘gracious living’.

It might sound strange to pair engines with the concept of gracious living, but in truth Kohler’s units offer a leading edge of technology and innovation and are used in many applications that improve the quality of life, whether they are used in agricultural vehicles that help put food on our tables, construction machinery that build housing or infrastructure, or in generator-sets that provide power to homes, hospitals, or the data centers that keep our world connected.

“The growth that Kohler Engines has experienced in recent years is the result of tremendous work and close collaboration that has led our customers to becoming true partners, with whom to strengthen value propositions and gain access to different market segments, and to sharing resources such as expertise and infrastructure,” said De Giglio. “Demo Days was designed precisely with this intent.”

Among the machines that have been displayed at the Demo Days, are the multipurpose compact loaders by Finland-based Avant Techno that mount Kohler gasoline engines since the early 2000s when the Avant 200 multipurpose loader was equipped with a Kohler V-twin CV20S engine.

With the introduction of Tier 4F emissions regulations in the US, Avant Techno started to mount Kohler KDI 1903 TCR diesel engines with diesel oxidation catalyst (DOC) on its larger wheel loaders such as the 760i model. To meet Stage 5 for its bigger loaders sold in Europe, the Finnish company adopted the same Kohler diesel engine with DOC and diesel particulate filter (DPF).

Olli Kurki, sales manager at Avant Techno, said that Stage 5 emission stage posed the challenge of fitting the engine in the limited space of the machines’ rear chassis: “The Kohler solution is very compact and fits in the space that was available; the engine’s high-power output is ideal to match the demand of the hydraulic attachments but at the same time operation is quite economical in terms of fuel consumption.”

Avant Techno smaller loaders nowadays mount Kohler gasoline engines with electronic fuel injection (EFI) as for example the Avant 225 loader, a 350-kg multipurpose mini loader that is equipped with a 25-hp (19 kW) Command PRO EFI ECV 730 unit.

Another manufacturer that mounts Kohler gasoline engines is Cormidi, which equips its C55 and C85 crawler dumpers with Kohler single-cylinder engine types CH270 and CH440 respectively certified for EPA and EU Stage 5.

Cormidi’s C55 crawler dumper is a popular machine for the rental market in the US, Europe, and Oceania

Cormidi’s Marco Martella said that these machines are well sold in Europe, USA, Asia, Australasia, and New Zealand, and are well appreciated in the rental market: “These machines are often rented, including by users that eventually make the decision of buying the machine.”

According to Martella, one of the reasons for Comidi to choose Kohler engines was the ready availability of spare parts all around the globe. “Our customers put a lot of importance on aftersales,” he said. “We have also been looking at more flexible configurations, as for example the larger fuel tank compared to those of competitors and the possibility of a different positioning for a better access, or the Kohler Quad-Clean cyclonic air filter, which is a key characteristic for a machine with the engine in a low position, close to dust and dirt.”

For example, Cormidi’s On Tracked Dumper 55 HI mounts a Kohler Command PRO CH 270 with 7 hp (5 Kw) output at 3600 r/min and 14.2 Nm torque at 3000 r/min.

Pierpaolo Grassigli, Marketing Sales Support manager at Kohler Engines, summarized some of the characteristics of the mono-cylinder air-cooled Command Pro engines that are especially appreciated by professional users: “The Oil Sentry technology by Kohler protects the engine from potentially harmful low-oil conditions, while Fuel Secure allows to transport the unit without worries. Our heavy-duty Quad-Clean air filter protects the engine even in extreme dirt conditions and the large metal fuel tank means less filling and ultimately more productivity.”

The Series 5 wheel loader by Kramer Werke mounts the very compact Stage 5 KDI engine by Kohler in the limited space available under the rear hood

Among the manufacturers that chose Kohler diesel engines, JCB adopted the KDI 2504 on its new 90Z-2 midi excavator; the engine delivers 74 hp (55 kW) maximum power and 300 Nm torque and complies with Stage 5 regulations with a DOC+DPF aftertreatment system.

According to David Rossi, product manager at Kohler Engines, the torque response of the KDI engines is a key feature for applications such as the JCB excavator: “The engine delivers 315 Nm of torque already at 1500 r/min and its high torque reserve allows the machine to deliver a higher load response during digging cycles thus increasing productivity and efficiency up to 10%.”

Kramer Werke adopted the KDI 2504 TCR diesel too on its Series 5 wheel loaders models 5075, 5085 and 5095. In this case, Kohler reported that the Stage 5 solution was chosen mainly for the engine impressive performance in power and torque combined with its compactness, in fact the engine was mounted in the back of the machine, in a very limited space, allowing to maintain the same visibility for the operator.

The bigger model in the KDI range was the choice of Wille Machines, a Finnish manufacturer for urban areas maintenance vehicles, for whom the environmental aspect when operating its machines is a key concern; in fact the Wille 675∆ machine is powered by a KDI 3404 diesel which utilizes an SCR aftertreatment to comply with the Stage 5 emission standards but can also use 100% HVO fuel which reduces overall CO2 emissions by up to 90% and curbs other engine emissions thanks to the very low sulfur content.

The 675∆ is a machine that handles a wide range of working attachments thanks to a sophisticated and powerful hydraulic circuit, with two hydraulic systems and a variable displacement pump with load sensing.

“The four-cylinder 3.4-L KDI 3404 turbocharged diesel engine is the most compact in its class and has a reduced fuel consumption compared to the Tier 4F configuration,” said Francesca Rinaldi, associate product manager at Kohler Engines. “This version of the 3404 unit has a power output of 150 hp (112 kW) at 1800 r/min and an impressive torque of 650 Nm already at 1400 r/min.”

All the KDI engines with aftertreatment have the option of mounting the system directly on the engine, or remotely on the chassis. The KDI 3404 has also some maintenance-friendly features, such as a Poli V service belt, hydraulic lash valve adjustment that requires no maintenance, a smart oil pump, and 500-hours maintenance intervals.

For aerial platform manufacturer CELA, the power choice was a diesel-electric hybrid: a Kohler K-HEM system mounted on its first hybrid dual telescopic boom tracked platforms: the Spyder DT28 and DT 30.

Cela’s production manager, Aldo Arcari, said the choice of the hybrid system for the Spyders originated mainly by the need of having an engine without DPF because the machine duty cycles were not reaching the temperatures necessary for regeneration. “The solution was to have a Kohler K-HEM 19 parallel hybrid system using an endothermic engine with a power below 25 hp (19 kW), thus eliminating the need for a regeneration system. This engine is paired with an electric motor of adequate power that supplies the peak energy required by the application because, in our case, the maximum required power is generally of short duration.”

Arcari added that it was necessary to also install a properly sized battery pack that powers the electric motor and is charged by the diesel engine when reduced power is needed for the application; in this case the choice fell on li-ion batteries by Flash Battery.

The Kohler K-HEM 19 hybrid consisting of a 24-hp (18-kW) KWD 1003 diesel engine and a 48V electric motor that delivers up to 20 hp (15 kW) of boost power. This configuration equals the power output of the previous diesel solution that was delivering 45 hp (34 kW).

Paolo Zaccarelli, Kohler Engines’ product manager, pointed out how Kohler can deliver the entire hybrid system, with diesel engine, electric motor, and hybrid control supplied by Curtis – now part of the Kohler group. “The whole system is integrated by Kohler and the power management is optimized for each application.”

Zaccarelli added that the Kohler K-HEM is available also in a versatile version, with a mechanical clutch that disconnects the electric motor from the diesel engine. “This solution allows to stop the diesel engine and power the machine solely on electric, while having a simplified machine design thanks to less redundancy in components.

“This configuration also allows the OEMs to cover multiple levels of powers so reducing their ranges. And a higher efficiency can be achieved replacing hydraulic motors and activators with electric ones.” 

Zaccarelli concluded by adding that a project with the versatile version is underway for a new Cela 40-mt platform, and there is also an evaluation for the introduction of a plug-in version in the future.

Finally, Kohler is working at the hybridization of the KDI range, with an electric motor dedicated to this project and capable of delivering high performances in a very compact size.

The platform will be available in 48 and 96V variants and timing of introduction is planned to allow for machines’ transformation in view of next Tier 5 stage of emissions.

The assembly line of KDI engines at Kohler Engines’ headquarter in Reggio Emilia, Italy