Illinois Thresher Steam Engine

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Winching the Illinois engine onto our lowboy, ready to go.
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Restored Illinois engine #152;
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The Illinois at one of many shows and parades.
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 Several people to help restore the Thresher steam engine.
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Boiler and method o mounting brackets, illustration from an Illinois Thresher Company catalog.
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Restored Illinois engine #152;
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Ready to leave Schultz's home in March 1997.
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Restored Illinois engine No. 152.
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October 1996, first visit to Don Schuhz in Macedonia, Iowa.
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Actual sandblasting of boiler by Oly Maas.
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Moving unit outside for sandblasting.
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Duane Roll uses an air descaler to remove paint and grease.
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Painting and getting ready for reassembly of parts..

35545 Highway 69 North, Forest City, Iowa 50436

History of Manufacturing

William N. Rumely, founder and president of the Illinois Thresher Company, was also the Dean of Manufacturers of threshing machinery in America. He ‘devoted his entire life to engineering and the construction of machinery for threshing small grain and hulling seed. He succeeded the presidency of the M. Rumely Company upon the death of his father. Later disposing of his interests in that company, he came to Sycamore and founded the Illinois Thresher Company, where he manufactured his products.

The Illinois steam traction engine was a double geared, rear mounted steam engine. Every shaft and gear had a double bearing and there was not a stub shaft or bracket on the engine. The boiler was built larger in size than was required by the accepted engineering standards at the time. All boiler steel was rated at 60,000 pounds tensile strength, it used the best quality of open hearth boiler steel and was a butt strap seam type on all 25-80 HP boilers. It was the open bottom, direct flue, locomotive type construction. Only the highest grade of steel was used for the tubes. It was built to comply in every respect with the specifications laid down by the Society of American Mechanical Engineers and with the strictest boiler laws of all states and Canada. They were surrounded by copper ferrules to insure a strong and lasting union. Seven-eighths inch stay bolts were placed every 43/8 inches and 49/16 inches from center to center in the firebox. The boiler contained 42 2 inch flues 100 inches long. All holes in the flue sheet were drilled instead of punched to insure exact hole sizes. These were provided at both ends with large beaded heads. The steam dome was very large in size, well braced with butt strap construction, and located in position to furnish a large supply of dry steam at all times. The arch type firebox was of generous size, furnishing a chamber for perfect combustion of fuel. Their boilers were tested under hydrostatic pressure of 225 pounds of cold water and working pressure at the factory was set at 150 pounds.

After the engines were mounted, they were tested again under steam pressure of both belt and traction power. The Arnold single eccentric was the reversing device used on the engine. They used the double ported valve. This valve was not commonly used by other engine builders because of its high cost. The Illinois Thresher Company made the following three steam traction engines: 20, 22, and 25 HP.

The largest of the three was the 25 HP steam traction engine, as shown in this article. The 25-80 HP engine had a 10′ bore and a 12′ stroke. This steam engine was a coal, wood or straw burning engine with cab and jacket. The engine frame was the self-contained Corliss type. The cylinder, steam chest, guides and pillow block were all combined into one casting of especially tough, close grained iron that was perfectly machined and made susceptible to lubrication. The boring of the cylinder and cross-head guide was done in one operation, both tools being carried by a boring bar which insured perfect alignment of all parts. The friction clutch could be engaged or disengaged at high or low speed. The draw bar was securely attached in close proximity to the huge brackets which took the forward thrust from the rear boiler mounted axle. It was built to withstand several times its normal strain. Heavy cross bars held it in place against side thrusts. Only 63 units were built, starting at 100 and going to 163. Today only six of all three sizes remain, and only two of the 25-80 HP are known to exist.

First Owners

Engine #152, a 25-80 HP, built in 1924, was purchased from a dealer in Wichita, Kansas, along with a 36′ Illinois wooden separator. It was taken to a farm a short distance west of Wichita, Kansas, where it was used during the life of the big threshing era. When the era was over, the engine and the separator sat side by side on the farm. Then William F. Merhoff of Newkirk, Oklahoma, bought the engine from where it rested. The separator which sat beside it had totally rotted down. Merhoff took the engine to his place and found another 36′ Illinois separator which he used at early shows in the 1950s. In July of 1960, William Merhoff put the engine up for sale.

On a trip to Oklahoma in 1966, Donald Schultz from Macedonia, Iowa, and Doc Murphy stopped to see William F. Merhoff and after much conversation, Donald Schultz now owned the engine. Doc Murphy, a good friend and neighbor to Donald Schultz, already owned a 20 HP Illinois. Schultz and Murphy ran the engine off and on for the next 10 years. For the last 20 years, the engine has sat in the shed without being fired. Both Schultz and Murphy have aged and Schultz, at 90 years old, finally decided to sell the 25 HP Illinois.

In 1996 Don Schultz advertised the engine for sale in the September/October Iron Men Album magazine. Ron Holland, of Forest City, Iowa, drove down to inspect the engine. After two trips down to Macedonia to negotiate a purchase, a third trip was made along with a semi and low boy to haul the engine to its new home.


First Steam Up Day on June 7, 1997, with a picture of several people who put in countless hours to help with the restoration project. Left to right: Keith Maas, Jerred Ruble, Norman Taylor, Duane Roll, Ron Holland, Bill Hanson, Oly Maas. Not pictured, Paul Branstad.

Ron and some of his crew from Ron Holland Housemoving, Inc. and other friends immediately put the engine in the shop and started dismantling, cleaning, and repairing. All of the piping was removed and replaced with Schedule 80 piping. The front axle, rear wheels, guards, levers, and tanks were removed, sandblasted, primed and painted. The differential was dismantled and spider gears re-bored and new pins made. Many hours were spent scraping, wire brushing, descaling, sandblasting, and cleaning, to get the painted parts ready for assembly. A new metal roof and two new support brackets were made for the canopy.

It was really exciting to see the engine going back together with newly painted parts, polished brass, refinished wood knobs, and new insulation on the engine with a new stainless steel cylinder jacket. The boiler and gearing on this unit was in excellent condition and showed no signs of pitting or deterioration, which made it an easier restoration. When all the painting and assembly was complete, including a new relief valve and new plumbing, we called in a professional sign painter to do the lettering and detailing.

After a cold water hydro test was done, June 7, 1997 finally arrived. We rolled Engine #152 out of the shop door. With it full of water, we built a fire in the boiler. A large crowd was on hand as we anxiously awaited the steam to build up. We checked again to see if the proper valves were open or closed as needed and all greased and oiled parts were ready. It was surely an exciting time to open the throttle and see the engine turning over with steam for the first time in many years.

As that Saturday of June 7, 1997 came to a close, most everyone in our small town, with a population of 4,500 in Forest City, Iowa, knew we had fired #152. People within a two to three mile radius could hear our excitement, mainly because people in attendance wanted to pull the rope for one of the three whistles. That day we had a steady stream of people stopping by our shop checking out Engine #152.

1997 was a busy year for the Illinois, as it was hauled to several shows, including Ageless Iron in Ankeny, Iowa, and also several parades. It mostly sawed lumber and threshed oats or was being displayed. It was the featured engine for the Hanlontown Threshing Days Show. As the season came to an end, we decided to replace all the flues. Now Engine #152 will be ready for next year after its long winter sleep.

I would like to thank a few special friends for helping with the restoration: Oly Maas, Duane Roll, Norman Taylor, Jerred Ruble, Bill Hanson, and Paul Branstad.

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