TRACTOR PROFILE
Eimco /Harris
Power Horse Tractors
BY JIM O’CLAIR
Model M that was unsuccessfully pro- duced by General Motors (Editor Dan Strohl’s article on the Samson appeared in our August ’06 issue). The average farmer/owner had to be experienced in the operation of horses or oxen, however, in order to use the equipment safely. Pull- ing back on the reins stopped the tractor, but, as with horses, pulling back too hard means “back up,” and if the tractor was in a higher gear, the driver might not have enough time to stop the tractor from backing over him. Many of the later Har- ris models had a driver’s seat, control pedals and steering levers, depending
on their primary usage, but some Harris
Power Horses were still rein-controlled.
The later Harris PH- 40 model was a forward control tractor with four-wheel
chain drive and used the four-cylinder
F- 162 Continental engine.
In 1953, Harris introduced several new
models, including the PH- 53. The engine
on the PH- 53 was a Chrysler industrial
six-cylinder rated at 217.7-cu.in. It produced 48hp at very low 1,800 RPM. The
PH- 53 was 95 inches long with a wheelbase of 50 inches. The parking brakes
were contracting band-type and were
also used to steer the tractor. The transmission was a four-speed, with top speed
in 4th gear rated at 13. 5 MPH at 2,000
RPM. An adjustable centrifugal governor
could be set between 1,000 and 3, 200 RPM.
Despite its long wheelbase and because
of its four-wheel drive, the Power Horse’s
turning radius was only 56 inches on 24-
inch tires. Other models released in 1953
included the model F6WC and F8 WC, both
four-wheel-drive models with Chrysler
six- or eight-cylinder industrial engines,
respectively. An additional model FDWC
was produced with a two-cylinder Detroit
Diesel engine. Harris Power Horse production was discontinued in 1964, but
the technology in the design led to the
modern four-wheel-drive skid steers we
see on construction sites and many other
places today. Classic original examples
can sell for $5,000 to $6,000 when fully
restored, but other unrestored units are
still in operation today.
The Power Horse was considered one
Albert Bonham of Salt Lake City, Utah, designed the original Eimco Power Horse in the mid-1930s.
They were only produced under the
Eimco Company brand name for a few
years. They were then sold under the
Bonham name until the early ’40s. The
Power Horse tractor was built at several different facilities in Utah. Parts for
the Eimco and Bonham units were purchased from Allis-Chalmers, including
the hood, transmission and their model
B- 125 engine. The Chalmers B- 125 engine
had a 33/8 -inch bore and a 31/2-inch stroke
rated at 22.3hp at 1, 400 RPM. The hood of
the Power Horse closely resembled the
Allis Chalmers B and WC model tractors
of the ’30s. Allis-Chalmers showed some
interest in the design from their previous dealings with the Bonhams, and
of the first “skid steer” tractors.
eventually bought the patent and hired
Albert Bonham in 1942 in the hopes they
could produce a more marketable Power
Horse by war’s end. Allis-Chalmers built
only one known prototype and never produced any of the tractors under the A-C
name. The Harris Manufacturing Company of Stockton, California, obtained
production rights and began marketing
the Power Horses in 1949. Production
continued up into the early ’60s.
What was unique about the Power
Horse was that the original units had
no seat or steering wheel, controls were
attached to livestock reins and were
routed back to the buckboard or farm
implement behind them where the driver
would sit and man the controls. It was
supposed to be a solution for the farmer
who wanted a tractor but could not afford
all the new shaft-driven
pull-behind farm equipment that went with a
new tractor. The reins
were attached to levers
on either side of the
tractor, controlling left
turn or right turn with a
simple pull of that rein,
or stopping by pulling
on both reins together.
This design was similar
to the 1918-’ 19 Samson
76 HEMMINGS MOTOR NEWS • OCTOBER 2009
