Deutz AG produserer motorer i Køln i Tyskland.
Firmaet ble etablert i 1864 som N. A. Otto & Cie av Nikolaus Otto, som oppfant firetaktsmotoren. Andre berømtheter har jobbet for Deutz, som Eugen Langen, Gottlieb Daimler, Wilhelm Maybach, Prosper L'Orange, Rudolf Diesel, Robert Bosch and Ettore Bugatti.
I de første årene var Otto og hans partner Eugen Langen utelukkende opptatt av å produsere stasjonærmotorer. Midt på 1870 tallet, så var den tekniske direktøren, Gottlieb Daimler opptatt av å begynne med bilproduksjon, hvilket Otto ikke var like begeistret for, og han valgte derfor å overføre Daimler til Deutz sin avdeling i St. Petersburg, for å redusere innflytelsen til Daimler på de andre i ledelsen av Deutz. Dette fikk Daimler til å slutte, og i samme slengen tok han sin gode venn Wilhelm Maybach med seg.
Deutz also used to produce agricultural machines such as combine harvesters and tractors, as well as commercial vehicles such as lorries and buses. However, in 1995 Deutz sold its agricultural machinery division – Deutz-Fahr – to the Italian company SAME, forming SAME Deutz-Fahr.
Deutz's head office is in the Porz district of Cologne and as of 2004 was manufacturing liquid and air-cooled diesel engines. The larger engines in the Deutz range were manufactured in Mannheim, at a production facility that once belonged to Süddeutsche Bremsen-AG as MWM-Diesel. Deutz also have production facilities in other countries including Spain and a joint venture production facility in China. After Deutz took over, the plant specialised in marine engines. This facility now produces engines for marine and power generation which can run on either fuel oils or fuel gases (including landfill gas).
During World War II, the company was ordered to produce artillery and operated under the name Klöckner Humboldt Deutz AG (KHD); both names have been, until recently, used since, even by the company itself.
Commercial vehicles powered by Deutz engines were popular from 1960 to 1980, sold under the brand name Magirus Deutz.
Deutz engines are available in the power range 4 to 500 kW, with air, oil or water cooling and with life expectancy of 20,000 and 30,000 running hours TBO (Time Between Overhauling) on rebuilt and brand-new units.
Parts and service are available worldwide. In the United States and Canada, a network of distributors was established a few years ago, providing parts and service in North America.
Deutz-powered air-cooled machines are well-suited for many applications since they cannot freeze or boil-over during normal operation.
Deutz also manufactures oil-cooled engines. These can provide the same power as other engine designs, but in a smaller package, since they don't require the additional space to house a radiator.Mal:Citation needed Deutz also makes engines with a tandem oil cooler/radiator configuration; these also do not require antifreeze or coolant agents.
Deutz also has line of economical liquid-cooled engines.
In 2007, the "Deutz Power Systems" division was sold to 3i, and Deutz AG now concentrates on producing and selling compact engines under the Deutz brand only. They are focusing on manufacturing engines only for the customer, without competing for the entire piece of finished machinery.
On October 1, 2008, the former Deutz Power Systems division received a new, old, name MWM (Motoren Werke Mannheim AG). The company traces its roots to Karl Benz, who set up the foundations of the company in 1871. After splitting the engine business off from Benz AG, it became Motoren-Werke Mannheim AG. Klöckner-Humboldt-Deutz AG took over in 1985, later becoming Deutz AG. After spinning off Deutz Power Systems, the company has made a full circle back to MWM.
In 2012, SAME Deutz-Fahr sold a majority of its holding in Deutz AG to Volvo, selling more than 22 Million shares. This puts Volvo's ownership at just over 25%, and makes them the largest share-holder. SAME Deutz-Fahr retained 8.4% equity in the company.