The four wheel drive general purpose tractor was put out by the
Massey-Harris Company, Racine, Wisconsin, in 1930 according to R.
B. Gray in his book, ‘The Agricultural Tractor.’ He
describes the tractor as being made in 4 widths of tread to conform
to different row spacings. With the 2 hand-operated brakes
operative on both wheels on one side or the other, it was claimed
the tractor could be turned within a 6 foot circle. The rear axle
assembly was free to oscillate about a horizontal axis thereby
giving flexibility in traveling over uneven ground.
In the March 31, 1963 Implement Tractor Product File Issue,
Elmer J. Baker, Jr., has this to say about the Massey-Harris four
wheel drive tractor: ‘When the Massey-Harris four wheel drive
G.P., perfectly engineered, went out to Nebraska it was with the
expectation that pulling records in proportion to weight would be
broken. They were not. The G.P. pulled 79? percent of its operating
weight in pounds at the drawbar, even though it was pulling with
four 38 by 8 wheels, each one equipped with 20 lugs, 3?’ high.
With all those bite surfaces or ‘gears’ in the dirt, you
might call it, the G.P. did not equal the then current records of
several two-wheel drive models.’
For example the Fordson (kerosene test) pulled 86 percent of its
weight, the John Deere D 90 – 3/4 percent,
the Case L – 85? percent and the Bradley (a mail order brand) 99?
percent.
There are conditions where four-wheels will pull more than two
wheels, but neither will pull a lot. That is in bog work. Even
there water buffaloes are better; they won’t get mired
down.
If justice had been done, both the McCormick and John Deere ASAE
medals should have been awarded ‘Gus’ of the Massey-Harris
experimental staff for the consummate job he did in designing level
riding shovels for a mountain-goat tractor. I think he did it with
parallelogram mounts with grasshopper joints at every connection.
They are quite standard now for corn planters.
The Massey-Harris G.P. (General Purpose) was the most perfectly
executed designing dream that ever proved that two plus two do not
necessarily mean four. This model was completed about 1929 and was
tested on gasoline at Nebraska from May 5 to 27, 1930.
Considering the mechanical intricateness and the employment of
novel elements of design, it was a minor miracle that no need for
repairs or replacements developed. For the Massey-Harris G.P. was a
four wheel drive, and it had devisements to avoid winding up on
inflexible metal while traversing rough ground that no automotive
vehicle had ever had before. The front axle mounting was standard
so far as movement and turning of wheels was concerned. But the
rear axle was an eyebugger. If there were nothing to stop it, it
would have been possible to rotate the rear axle around the center
drive and differential gears.
There was corresponding difficulty working out cultivating
attachments which would follow the axle oscillations while keeping
the shovels exactly at the predetermined and set depth of
cultivation, measured from the ground surface. And that is just
what that designer did. It was the most perfect job of traversing
rough ground to grade level ever accomplished.
Now, and smart ‘Lit’ could have told you then, and now,
that if two drive wheels would pull just so many pounds in a
specific condition, four drive wheels could pull more. And yet that
is simply not true, anymore than four lies are better than two when
deceiving one’s wife.
This model was rated 15-22 HP and in the Nebraska test the
maximum brake horsepower developed was 24.84 and the maximum
drawbar horsepower developed was 19.91. The tractor was equipped
with a Hercules engine with a bore of 4′ and stroke of 4?’
running at 1200 rpms. Chasis number of the tractor was 300089 used
in this May 1930 Nebraska test. I know of around 30 tractors like
this still around the country. ‘The one here at Makoti is owned
by Edward Dobrinski and is tractor #301864, a 1930 model.
