Rehlko showcases engine applications at third ‘Demo Days’

There was a lot going at Rehlko’s annual demonstration showcase, but one development that would have caught the eye of its OEM customers was its plan to develop a dual certification version of the KDI2504 55kW diesel engine suitable for use in Europe and the USA.

The engine manufacturer, which rebranded last year from Kohler Energy following its acquisition by private equity firm Platinum Equity, currently sells two versions of the engine; a Stage V certified unit for Europe with both DOC and DPF treatment, and a Tier 4 Final model for the US with only DOC.

Antonio Riccio, product manager global diesel engines at Rehlko, said its OEM customers had been asking for a global product because the benefits of standardization outweigh the cost of having both DPF and DOC on all engines.

Antonio Riccio, product manager global diesel engines at Rehlko, pictured at the Demo Days event. (Photo: Power Progress)

Riccio, speaking to Power Progress International at the company’s third annual Demo Days event at its plant in Reggio Emilia in northern Italy, said there was a 50/50 split between engines produced with the two specifications and that customer preferred to have a single specification engine.

Equipment on show at the 2025 Rehlko Demo Days event. (Image: Rehlko)

The company’s larger KDI engine, the KDI3404, is already available with dual certification and is being used, for example, by Wacker Neuson in North America.

“These KDI2504 engines have multiple ratings and certifications because you can have Tier 4 Final version, a Stage V version and a less regulated countries engine”, said Riccio.

“And we are working to reach also the so-called double certification on these engines because we want to give to our customer the possibility to just buy one spec for the entire world.

“We are capable of reaching this double certification and we have already tried it in our test bench. We are working on calibration of the engine, to have the best calibration for the US market, because this is the most impacted market for this kind of double certification engine.”

Riccio said the development would be good for manufacturers both large and small, with lower volume OEMs - who may only export a small proportion of their machines to the US - seeing a particular benefit in only needing to stock one engine. The dual-certified engine could be ready in 2026.

The engine manufacturer used the Demo Days to showcase seven machinery manufacturers who are using its engines, comprising Wackler Neuson, TerraTec, Moffett, Rotair, Argo Tractors (Landini), Fiori and US-based Walker Mowers.

Wacker Neuson case study

For its part, Wacker Neuson highlighted how Rehlko’s engines had played a significant role in the development of its new WL950 wheeled loader, launched earlier this year. This ‘entry level’ machine has a 0.85m3 bucket capacity and is powered by a KDI1903TCR engine.

Wacker Neuson’s WL950 compact loaders - in the colours of its brand Weidemann - on show at Rehlko’s Demo Days. (Photo: Power Progress)

Max Weymann, manager technical products at Wacker Neuson, speaking at the event, said a key benefit of the KDI1903 was its suitability for transverse installation rather than the longitudinal design of its previous models; “from our point of view we had the best engine you can use for a transversal engine installation.”

The transverse arrangement, he said, resulted in “cross flow of air through the bonnet, which leads to a huge reduction of the temperature compared to what we had in the past. And as a result of this, we can see a lot of effects, for example, that we have the chance to reduce the size of the cooling package with a huge impact on the cost.

The orientation also allowed Wacker Neuson to reduce the overhang of the rear, which allows to improve maneuverability through slope transitions, which he said was a benefit for many customers, especially in construction.

“It seems to be a small decision”, said Weymann, “but in the end you can earn a lot of benefits.” The OEM is using Rehlko KDI engines on all nine of its wheeled loaders.

Small engine strategy

Stefano Calzi, senior manager, product marketing, global diesel engines at Rehlko, talking about the company’s smaller diesel engine, the 18.9kW KSD1403 - produced in Aurangabad, India - said a growing number of OEMs were using the power units. These include JCB on one of its 2.5t mini excavators, Wacker Neuson on its G14 portable genset in the US, both Avant Tecno and MultiOne for their respective compact loaders, and portable air compressor specialist Rotair.

The transverse engine orientation on Wacker Neuson’s WL950 wheeled loader. (Image: Power Progress)

Calzi said this small engine category was the one that was under the greatest pressure from the development of battery power or hybrid options. He told PPI that Rehlko had developed a complete hybridisation product a number of years ago and worked with several OEMs - including one aerial platform manufacturer - but ultimately had found a limited market.

He said the company preferred to focus on continued development of diesel engines, with its customers able to develop hybrid or range extender options themselves using its engines. For example, Fiori, the Italian manufacturer of concrete trucks and site dumpers, is offering range extender options on its new line of site dumpers, using Rehlko engines.

“What we see is that bringing electronic engines to this sub-19kW power category, which is dominated by fully mechanical and very traditional engines, is really an enhancer for the OEM to have a better integration of the machine”, said Calzi, “It’s a solution and an enabler for a connected machine.

“What we see is an increasing trend of this type of thing. Of course, there is a trend also for electric vehicles, but we see the adoption rate is much lower than expected and we still see diesel engines are a preferred source of power, especially when the job is very professional.

“Battery power is gaining in some niches, for some very small equipment”, he added, “but we believe that bringing electronics into this space is really an answer and an enabler for OEMs to have connected machine… that makes it easier for them compared to installing traditional mechanical engines.”

The Landini Trekker 3 crawler tractor is fitted with a Rehlko KDI2504 engine. (Photo: Power Progress)

He said; “There are some niches below 19kW where pure electrical makes a lot of sense, but we still see a huge space for internal combustion engines, particularly diesel.”

Calzi also addressed the question of cost, and the impact of the high US tariffs for Indian-made products; “We believe that we still have advantages because having a complete developed supply chain in India, it helps a lot to keep the cost down. So that will help us”.

New brand-building

The engine manufacturer is also using Demo Days - which is attended by European press as well as OEM partners - as part of its strategy to build the Rehlko brand.

Nino De Giglio, Rehlko’s director marketing communications and channel management, said the name of the company may have changed – as a consequence of Kohler’s divestment to focus on its non-power businesses - but “in reality, we are the same people, the same products, with the same commitment from all our staff to serve our customers”.

He highlighted the global footprint of the business, with manufacturing facilities in the US, India, Italy and China; “We have been in this industry for more than one century and we continue to make design and test engines, gasoline and diesel up to 115kW.”

For Eric Fontaine, the president of Rehlko’s Engines division, speaking at the event, Demo Days was “a unique opportunity to experience machines and engines working together in the field.

“It’s always a really good opportunity to be able to see how the two come together to satisfy customers out in the field. The event is more than just a demonstration. It’s a chance to exchange ideas, to see technology in action and to understand how Rehlko engines can enhance the performance of your equipment.”