Allis-Chalmers M7 Restoration

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Richard and Peg Liekweg's 1944 Allis-Chalmers M7 snow tractor equipped with its M-19 rescue trailer, designed for use by the U.S. Army Air Corps as a rescue vehicle in remote northern bases.
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The M-19 trailer used with the M7 to haul downed aviators.
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A mannequin clad in U.S. Army Air Corps gear in the M-19 rescue trailer.
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Peg and Richard Liekweg with their 1944 Allis-Chalmers M7 snow tractor.
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The M7’s flue is shown here in the up position, allowing the pre-heater to keep coolant warm in frigid temperatures. Air forced over the hot engine manifold heated the passenger compartment.
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The M7 snow tractor had interchangeable skis and wheels on the front axle; both could be in position at the same time. Here, the skis are carried on the side of the hood, almost acting as fenders.
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The Liekwegs’ 1944 Allis-Chalmers M7 snow tractor, no. 181 of 291 built. The tractor is steered using a steering wheel; the tracks can be braked independently.
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The M7 has an under-hood pre-heater. Here, the flue (center left on the hood) is in the down position. The flaps on the hood are made from toolbox covers from an Allis Model B, C or CA tractor; the grille is a widened version of an Allis Model B grille. The gas cap for the auxiliary heater immediately in front of the windshield is also an Allis part.
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Detail of the M7’s treads.
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Detail of the speed chains inside the treads on the snow tractor.
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The Liekwegs are very protective of their restored snow tractor. Before Richard slides into the tractor’s compact cab (which features seating for the operator and one passenger, one in front of the other), he removes his shoes.
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The M7’s Army number is authentic. After sanding, part of the six-digit sequence was visible on one side of the tractor; the remaining two numbers could be made out on the other side.

Before Richard Liekweg climbs into his Allis-Chalmers tractor, he removes his shoes, sits on the side of the cab and slides in backward.

“I don’t want to get it dirty,” says the Iowa Falls, Iowa, man. If that seems out of the ordinary, so is the tractor: a 1944 Allis-Chalmers M7 snow tractor, designed for use by the U.S. Army Air Corps as a rescue vehicle in remote northern bases.

The Liekwegs’ Allis-Chalmers collection began more than 30 years ago with just one tractor and no place to keep it. That meant buying farmland, which led to other AC items: tractors, a combine, a Gleaner combine and implements. “Richard was raised on a farm,” Peg Liekweg says, “but I was a town girl.” Nevertheless, Peg’s love of farm things helped build a collection of Allis-Chalmers machinery, memorabilia, farm toys – anything Allis.

Northwoods relic

While vacationing in Alaska in 1999, the couple heard about a half-track Allis-Chalmers snow tractor. After seeing pictures, Richard and Peg decided to look at it for themselves. The owner had a wide selection of old military vehicles – government-surplus trucks, bulldozers and snow machines – for sale to civilians. The Liekwegs asked whether the snow tractor was for sale but couldn’t get anything worked out before they had to leave.

Back home in Iowa, they wrote the owner, again raising the possibility of buying the tractor, but received no response. Finally, they sent what Peg calls “a dartboard offer,” enclosing a self-addressed, stamped envelope. Three weeks later, they got an answer and bought the tractor.

Then things got complicated. For starters, the couple had no way to haul the tractor. They considered buying a new flatbed trailer. “I told Richard that customs wouldn’t allow us through if we had it all wrapped up in plastic to protect it from all the stuff on the roads,” Peg says. “So we bought an enclosed 16-foot trailer instead.” Peg sells antiques and collectibles, so the couple loaded the trailer full for the trip to Alaska. “It took about two hours to sell that load in Fairbanks,” she says.

Knowing the M7 wasn’t in very good condition, the couple stopped to buy parts at an Anchorage salvage yard they’d contacted earlier. From there they traveled back to Boundary, Alaska, on the Alaska/Canada border, loaded the tractor into the trailer and headed home. “At U.S. customs they asked what we had in the trailer,” Peg recalls. “When we said ‘a snow tractor,’ they said ‘that’s nice,’ and waved us through. They never looked at it!”

Sleeves rolled up

Back in Iowa, the Liekwegs began to see the immensity of the project. “We knew we’d have to do a lot of research on measurements, color and canvas, and where to get, make, buy or find parts for it,” Peg says. Government manuals helped with measurements and other information. The couple also contacted countless salvage yards, military surplus stores, Internet vendors and collectors. Soon they had a network of people who helped them find parts. Some parts were simply unavailable and had to be fabricated.

“The body was in very bad condition,” Richard recalls, “either rusted or the sheet metal was torn from running over rough terrain. Original parts had been removed, and to make space for inappropriate parts – like a Chevrolet car steering sector – they bent or cut sheet metal out of the way.”

Side body panels of sheet metal had to be replaced, a job Richard says he could not have done without help from his son, Brad, who had 20 years’ experience in the auto body business. Brad had access to sheet metal at salvage prices and the ability to bend it as needed.

“We think this one was used and abused,” Richard says, “because the original 4-inch elbow side panels had been extended an extra foot to carry game, supplies or whatever they wanted to haul.”

One-year run

In 1944, when all 291 Allis-Chalmers snow tractors were built (to military specifications), the federal government wanted to limit the military’s parts and repair requirements, so it mandated that Allis-Chalmers use a Willys jeep drive train. Accordingly, the M7 had a jeep engine, transmission and differential. Allis-Chalmers parts include a unique high-low auxiliary transmission, a 15-inch steering wheel, front wheels, hubs, rims, grille from an Allis Model B (widened 10 inches), gas tank under the hood, gas cap and two hood flaps (one used to check the oil and one to check the battery). Both flaps are toolbox covers from Allis Model B, C or CA tractors. The oval muffler is from the same vintage tractor too. The tractor’s exhaust is piped out under the engine.

A nomenclature plate to the driver’s right reads “manufactured by Allis-Chalmers Co., Milwaukee, Wisconsin,” and includes serial number and date of manufacture. Another plate showed shift patterns for high and low.

“We tore it down to the bare frame,” Richard says, “which had been cracked and welded with a gusset. I took off all that extra metal, straightened the frame, re-welded it and reinforced it. A rear cross-member supporting the engine had broken free and had to be welded back in just the right place so everything would line up.”

Fortunately, the tractor’s 4-cylinder L-head Willys MB engine didn’t need much work. “We were told the engine would run,” Richard says. “When we got home, we put in new points, plugs and a condenser, and a shot of oil into the cylinders got it started. Other than a carburetor kit, nothing major had to be done to the engine.”

Tracks and skis

The tracks were particularly fragile – and hard to replace. “You don’t find new ones anymore,” Richard notes. The salvage yard he located in Anchorage had an NOS track, idler wheels for the track, a new gas tank, differential and other components. “But all of it was inaccessible right then because of a 27-foot snow bank in front of the building,” he says.

The M7’s track ran on rubber pads with four steel cables inside. Time had taken its toll, and the rubber was deteriorated and cracked, allowing moisture to rust the cables until they broke. “When we put a new track on,” Richard says, “the old track fell apart in three pieces. Speed chains on both sides of the track held it together and assured us the track won’t shift sideways and slide off the rubber pads.”

That no. 60 roller chain, now on the outer edge of all M7s that have been used long-term, is a post-war addition found necessary to keep the machine from occasionally “throwing a track.” Even when new, the machine’s tracks sometimes came off in extreme situations, endangering operators: Replacing a track in deep snow conditions was almost impossible. At this late date, chains keep the tracks together, even though the cables that originally insured track integrity have broken.

The most difficult part to make was the skis. The first challenge came in selecting the right wood. “Oak came up in conversation,” Richard recalls, “but a local industrial arts teacher advised against it, because oak has a memory. It would eventually straighten itself out. So we ended up using ash.”

The Liekwegs modeled their skis on an original from another snow tractor. Sawed into 1/8-inch thicknesses, layers of wood were soaked in water for two weeks and then placed in a jig (made by the couple’s son-in-law, Ken) until completely dry. Gorilla Glue was used to bind the layers of dried wood, which were then returned to the jig. Based on that success, the couple made additional skis as replacement parts for other snow tractors.

A layer of whitewash

“When I lifted the toolbox lid under the rear seat, I saw it was painted whitish, and figured that was about the closest to the correct color of white,” Richard says. “So I had paint mixed up. We put splashes on the board and compared them until it was the dull white we wanted.”

Pieces were primed one at a time, fitted to the machine, removed, painted and set back together. The U.S. Army six-digit number on the hood had faded badly. Richard sanded one side but could only make out four of the six numbers. He then sanded numbers on the other side, where he was able to read the missing two.

Finding a replacement part – a flue – was another challenge. The flue was used to light a small gasoline engine pre-heater under the hood after shutting off the engine. “That kept the coolant warm,” Richard notes, “so the engine would start in really cold weather.”

While the Liekwegs were on vacation in Arizona, a New Jersey friend contacted the couple’s daughter in Iowa, saying he’d located the pre-heater and flue in Vermont. “Between the computer and cell phones, the deal was accomplished,” Peg says. “Aren’t cell phones wonderful?”

Topping it off

Finding the canvas proved to be an interesting experience as well. A New Jersey business had the Allis-Chalmers M7 top pattern and could make a replacement. “But they only cut white canvas once a year,” Peg says. “Otherwise it’d be green. So we had to wait until they performed machinery maintenance, when they would do the white.”

Finally, the canvas top was delivered – but the custom-made piece turned out to be too small. The couple further customized the piece, making cuts, adding gussets and altering the cab structure’s frame. “We’ll never take that off,” Peg says. “We’d never be able to get it back on.” With that sewn up, after two years’ worth of 40-hour weeks, the Allis-Chalmers M7 snow tractor restoration was complete.

Next: a trailer

On the show circuit, the Liekwegs’ prize began to draw attention. The couple was surprised to learn how few people knew what the M7 had been used for. “That’s when we started pursuing the M-19 trailers that were used to haul injured aviators,” Peg says. M-19 trailers (also Army issue) can be used on either skis or wheels; they were also used to haul parts and supplies.

Another official use was transporting a large, 14,000-BTU-per-hour aircraft heater and booster unit used to start plane engines. Airplanes forced down in isolated Arctic areas by bad weather needed such equipment to be restarted so they could be flown back to their bases.

When one turned up in Scotland, Peg says, “We told them to put our name on it and sent a check. Then we waited almost a year to get it at Fort Smith in the Northwest Territories in Canada.” The couple took their M7 to the 2004 Gathering of the Orange in Portage la Prairie, Manitoba, left it on display in an Allis-Chalmers museum, took the empty trailer and headed north.

Not surprisingly, the trailer was in bad shape. Fortunately, just enough good parts survived, creating patterns for replacements. “It took us another year or so to get that finished,” Peg says, “although we didn’t work on it full time.”

The canvas trailer top was made by a local upholsterer working from 17 photos, along with measurements from the original owner in Scotland. An old top found in a barn was a useful guide. “The original top was quilted, with insulation inside that looked a great deal like moss,” Peg says. “One side was green, and the other side was painted white.”

Then came the task of finding the right buckles and straps. Most straps today are made of nylon, but the Liekwegs needed cotton straps. And the canvas was held on with 128 wire hooks. “They were impossible to find,” Peg says. “So Richard made a tool and used high-tensile wire to make extra hooks. Green hooks on the green side, white hooks on the other side, and all put together with one rivet. I pounded every rivet without hitting his finger or mine.”

The Liekwegs’ trailer is on wheels, with skis mounted just above. The skis are metal-clad over laminated wood. “Our trailer is set up as we presume the military would have used it, with two litters, one hanging on the side and one on the floor,” Peg says. A mannequin in a World War II electric flight suit completes the effect.

“The electric suit was an inner garment used like an electric blanket to stay warm when plugged into the side of the airplane,” Peg explains. The usual Army outerwear was worn over the electric suit.

That kind of detail makes the display comprehensive and authentic. “Our goal,” Peg says, “was to do everything possible to restore the M7 to its original condition. Everything is as original as possible, except for the 1999 green wool socks the mannequin wears.” FC

For more information: Contact Richard and Peg Liekweg at
Bill Vossler is a freelance writer and author of several books on antique farm tractors and toys. Contact him at Box 372, 400 Caroline Ln., Rockville, MN 56369; e-mail:
Grateful acknowledgement is given to Clell Ballard who provided additional information for this article.
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