20601 Old State Road Haubstadt, Indiana 47639
The CX models were the last engines built for Sears, Roebuck
& Company at the Holm Machine Manufacturing Company at Sparta,
Michigan. Production began in mid 1912 with the 1 HP size and
continued until the early fall of 1913. At that time the factory
was closed down and all of the moveable assets were loaded on
freight cars and shipped to the new Hercules Gas Engine Company
factory at Evansville, Indiana.
The first engines of the new design in the new CX model were the
1 HP size. This first engine and the look alikes to come make
interesting stories in themselves. The first 1 HP size is shown
here. It was of attractive and simple design and with modifications
it would continue until 1929 in the Hercules line of engines. The 1
HP model CX had a dry head, large water hopper opening and an
igniter, battery and coil ignition system with a new design blade
trip. It was first offered in the fall 1912 Sears general catalog
at a price of $26.95. The write-up described the new 3 inch bore by
5 inch stroke engine, but the engine illustrated is a 2 HP model
CA. A special gas engine catalog of the time pictures the new 1 HP
engine, but the rest of the engines in the catalog are still the
model CA. It should be noted that the engine pictured has two bolt
flywheels and has the tag on the side of the water hopper.
1-Horse Power Economy Stationary Gasoline Engine
No. 47A4508 1-Horse Power Stationary Gasoline Engine. Price
THIS ENGINE GUARANTEED EQUAL TO ANY ENGINE SELLING FOR TWICE OUR
TYPEFour-cycle, water cooled.
PULLEY 4 inches in diameter ; 4-inch face
BORE-3 inches. STROKE5 inches.
CRANK SHAFTDrop forged. 1 Inches in diameter.
SPEED500 revolutions per minute.
FLOOR SPACE REQUIRED18x24 inches.
FLY WHEELDiameter, 18 inches. Weight, 44 pounds.
SHIPPING WEIGHT350 pounds
Shipped from our factory at Sparta, Michigan.
This new engine makes its appearance at the time when Sears and
the Hercules Buggy Company of Evansville, Indiana, were in
negotiation in regard to what eventually became the Hercules Gas
Engine Company. Whether Sparta or Evansville people were
responsible for this new design is unknown.
A unique feature of the new 1 HP engine is the cam gear governor
mechanism. In the accompanying illustration you can see the cam
gear governor parts. It consisted of a kidney shaped weight
attached at a pivot on the cam gear with its travel limited by
stops cast onto the cam gear. It had an attached threaded rod with
a spring and nut for adjusting the speed setting. When it swung out
far enough, the governor weight struck a small roller on the end of
the detent lever to cause it to engage the latch on the side rod.
In practical terms it was a poor mechanism. Speed adjustment was
poor and governing was erratic. It is no wonder that several of
these early 1 HP engines have had the mechanism removed from the
cam gear and the horizontal gear driven governor mechanism
substituted in its place.
Currently, I only know of six such engines and half of these
have been modified to the flyball governor. They all fall into the
26,000 to 29,000 serial number range. It is estimated that only 500
so described were built. The story that started out with the 1 HP
cam gear governor Sparta Economy will continue next month with the
four ‘look alikes.’