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Toward the end of the 1930s, the Great Depression’s choke hold on agriculture was finally relenting.
Foreclosures were becoming a bad memory of past troubled times. Money was seeping back into agriculture. And farmers, yearning for the advanced technology, began shopping for tractors in droves.
The time was ripe for a breakthrough in tractor design. And the newly formed Oliver Corporation pounced on that opportunity with a tractor that would define horsepower design for the next several decades.
Sleekly styled and packing a powerful six-cylinder engine that burned high-octane gasoline, Oliver’s Model 70 was a perfect metaphor for agriculture’s new prosperity.
When it was introduced in 1935, the 70 instantly stood out of the growing pack of post-Depression horsepower. Not only did it herald the beginning of better times, the 70 established Oliver as a serious contender in the world of farm machinery. Gone were the stodgy Hart-Parr designs replaced by a tractor designed for tomorrow. For a time, the 70 was the envy, as well as the template, for competing tractor engineers.
An evolution in power
The 70 was not a revolutionary design such as the Fordson or Farmall Regular. The tractor’s automotive styling, while advanced, was not a novel concept. Tractors bore similar styling in the late 1910s and 1920s.
While the 70’s engine was advanced in that it was designed to burn 70-octane gas (from which the Model 70 derived its name), such high-speed engines had been available since the mid-1910s.
Still, when it first hit the marketplace, the 70 instantly eclipsed styled tractors of previous eras. Oliver engineers, under the leadership of chief engineer Herman Altgelt, seamlessly merged auto design with agriculture purpose creating a standard other tractors would emulate for the next 25 years.
The 70 first existed as the Oliver Hart-Parr Row Crop 70. This was Altgelt’s first attempt at creating a new look for the rapidly growing Oliver Corporation. The popularity of the tractor quickly spawned two new versions in a fixed front- axle Standard and shrouded Orchard.
And then, in 1937, the 70 underwent further streamlining accented by a sloped-back oval grille and side panels bearing horizontal, rather that vertical, louvers. And gone was the Hart-Parr name from the tractor’s hood and side panels.
The power plants on new 70s stayed the same with this change. Farmers could choose from a high-compression engine (HC designation) or a version capable of burning kerosene or distillate fuel (KD designation).
Built to Oliver’s specifications by Continental, the differences between the two valve-in-head engine types are found in variations in cylinder head and manifold designs. (See other engine differences in the item below.) As a result, the HC turned out two more horses developing a maximum 28½ drawbar horsepower. Otherwise either engine had a displacement of 201¹⁄3 cubic inches and operated at 1,500 rpm.
These new 70s were also offered with a wealth of optional equipment, which reflected the optimism of the times. For example, buyers could add an electric starter. And many did just that, for by 1938, Oliver reported 75% of the 70s leaving its factory equipped with such an electric unit.
Then, too, Oliver offered an optional six-speed “double neutral” transmission. With a road speed of 13½ mph, this transmission grew in demand until it became standard equipment by 1944.
Steel wheel innovation
Still, for all its advances, the 70 was sold with steel wheels. Buyers could upgrade to rubber in 1937 as standard gear. Folks not trusting newfangled pneumatics could buy into an innovative approach to steel wheels. Oliver engineers fashioned an open skeleton wheel design that hosted various lug combinations, the most popular of which was tiptoe spades 4½ inches wide and 3 inches tall. Oliver promoted its Power on Tiptoe as a concept that would penetrate the ground to provide footing while minimizing soil compaction. A wide variety of variations were offered including dual rear wheels equipped with spade- or cone-shape lugs. But for all its uniqueness, Power on Tiptoe soon faded from the 70’s option list.
A great history of the 70 was written by Larry Gay in his book, A Guide to Hart-Parr, Oliver and White Farm Tractors 1901-1996. The book is available from MBI at www.motorbooks.com.