This 95-Year-Old Cummins Hvid Motor Still Runs
The Cummins legacy began with 6hp
Although we may all go crazy over the company's newest engines, the very first Cummins diesels weren’t completely of the company’s co-founder Clessie Cummins’ own design, as the fuel injection system was licensed from R.M. Hvid Company in 1918. R.M Hvid, a Dutch-born engine maker living in Michigan, owned the patents to the compression–ignition fuel delivery system in the United States and licensed out the technology to several engine companies in the early 20th century for a royalty fee. Watch it start up and chug to life in the videos below.
Prior to the Hvid invention, compression-ignition “oil” engines needed to have an air start and a high-pressure air supply system to fire up and run, making the early engines and their supporting equipment so large that the were stationary. It was the introduction of Hvid’s injection technology that finally allowed the diesel to become portable.
The Hvid is a four-stroke engine, with a typical intake and exhaust valves. In an over-simplified explanation of how it works, a small amount of fuel (along with air) flows into a steel cup adjacent to the combustion chamber during the intake stroke. On the compression stroke, the valves close and air is heated up as it is compressed in the combustion chamber and enters the cup through small holes. This super heated air detonates, forcing the rest of the mixture from the cup to the combustion chamber, beginning the power stroke by driving the piston. Finally the exhaust stroke completes the combustion process when the exhaust valve opens, allowing the gases to exit the combustion chamber. There is no ignition system other than compressed air, making the Hvid a finicky engine to start for those who don’t understand it.
Incorporated in 1919, Cummins began manufacturing engines within a couple of months. The Cummins Hvid engines were all single horizontal cylinders, fueled by diesel and known at the time as Cummins Oil Engines. They were designed to run at a constant speed, with a pulley off one of the flywheels running a leather belt. These engines were primarily used to run pumps, grind corn, saw wood, or for other machinery purposes around the farm or oil lease.
While there were various sizes and outputs, Cummins’ first engine was the 6hp model, which incidentally gained 1 hp from Cummins improving the fuel delivery process. After seeing the 6hp version at work, Sears Roebuck entered a partnership with Cummins to supplement capacity of the popular 1.5hp and 3hp engines from Sears’ main supplier of Hvid engines, The Hercules Engine Company of Evansville, Indiana. This partnership nearly bankrupted Cummins, as Farmers used the Sears sales terms to buy the engines for harvest but return them when the season was over for a refund. Despite this speed bump in the early history of Cummins, the Cummins engine company went on to be hugely successful.
Check out our videos of Cummins’ engineering guru, Randy Watts, explaining how an Hvid engine works and subsequently firing up a 95-year-old 6hp engine. While not the very first Cummins engine built, this well-preserved example was likely built by Cummins himself within a few months of the incorporation of Cummins Oil Engines. These 6hp engines displaced 140ci and made approximately 60 lb-ft of torque at about 500-600 rpm, weighing in at 1,100 pounds (750 of which were the twin flywheels). This particular engine was found in an oil field in Ohio and most likely drove a pump.