Hercules Engine News

By Staff
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20601 Old State Road Haubstadt, Indiana 47639

The story about trademarks used on 1 Hercules built engines
continues with the Thermoils. Sears applied for the trademark shown
below on November 10, 1916, and claimed that it had been in use
since August 16, 1916. It is stated in the spring 1917 Sears
catalog that the first model T Thermoils were built in October of
1915. On the trademark illustrated below, the letters and perimeter
were yellow and outlined in black. Some claimed the background was
red, but on my later model U Thermoil the background was blue. Both
yellow and black and yellow and black with a blue background have
been seen on reproduction decals. The shape is very similar to that
registered for the Economy engines as described in the previous
article. On the Thermoil trademark, the center circle depicts a
rotating wheel.

There is the question about what trademark was used on the
Thermoils between October 1915 and August 1916. The only clue is
found in the model T Thermoil instruction book. It shows an engine
as illlustrated at right with block letters on the water hopper.
Presumably, these letters were yellow with a black outline. Known
model T Thermoil serial numbers fall between 8 and 3743 with
production ceasing sometime in 1917. It is conceivable then that a
few hundred of the early Thermoils may have originally had the
block lettering.

The same ‘bow tie’ trademark continued in use during
production of the models U and UA Thermoils from 1919 to 1924. When
the contract with Sears expired or was terminated, Hercules
continued to market the same 7 and 9 HP model U A engines as
Hercules Oil Engines. They were painted Hercules green with red
stripes and with the standard Hercules trademark.

Here’s an interesting note and then a question. All known
model T Thermoil engines are of the 2, 5 and 7 HP sizes. The
instruction book also gives specifications for building foundations
for 1 and 9 HP sizes. Does anyone out there know of any 1 or 9 HP
model T Thermoils? If so, please send owner’s name and engine
serial number to me. These engines should not be confused with the
later 1 HP Model U built by Cummins or the later 9 HP model UA
built by Hercules.

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