Engine History

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A rotary mower with a 21 inch blade and an engine speed of 3,000 rpm has a tip speed of 187 mph.  If the operator walks at approx. 3 miles per hour the blade tip will pass over any given area 6 times, and a blade sharpened  3 inches on each end with the engine rpm at 3,000 only uses the first ½inch of the 3 inch sharpened length actually to cut grass. In order for the blade to cut the grass the full 3 inches of sharpened area the mower would have to travel 18 mph.
In 1951Clinton started production in Maquoketawith1 standard engine and 515 Model variations for the Original Equipment Manufacturers, {O.E.M}. By 1966 that figure had grown to 7 different engine categories, 181 standard engines and 7,677 model variations.
Clinton engines were sold and serviced by more than 62 Distributors, 845 Service Distributors, 12,000 dealers, 800 OEM Accounts in the United States and 88 outlets in off shore countries.
An estimated two-thirds of Clinton’s 2 and 4 cycle engines went into the power mower market.
In 1958 Clinton was given the title of “The World’s Largest Small Engine Producer”.
Clinton in 1952 introduced its own line of chainsaws for use in logging, cutting firewood, land clearing, agriculture, and utility companies and landscaping.
In 1953 Clinton introduced its own line of 5 hp. air and water cooled outboards mainly utilized for fishing and trolling. They were also used as “kickers”, auxiliary power, to get back to the home dock in case the larger outboard motor stopped running. In 1966 a larger 9.9 outboard was added to be utilized on larger boats.
During May of 1966 Clinton received the coveted “E” award for excellence in the export arena from the President of the United States. Clinton was the first engine manufacturer to receive such award.
Looking for different type of engine power Clinton designed a Wankel engine one/half the size of the 1600 Series Red Horse Engine in the early 1960s. While 80 % of design criteria was met in order to reduce high rpm and improve the engine torque calculations indicated a speed reducer would be required. This in turn created too heavy an engine so the project was canceled. A display at the Clinton Engines Museum contains blueprints and engineering sketches along with various engineering mechanical calculations.
Probably the cheapest and highest quality purchased part outside of hardware, was the Spark plug. Rarely was a reject on the assembly line or in the test department ever found. There were 2 pricing levels Purchasing had to deal with. If the plug went into an engine the cost ran from .06 to 10 cents. If the plug was for the Service requirements, the cost became .30 cents to which marketing priced out at $1.03 retail.  The plug manufacturer along with Purchasing always kept an eye on purchased requirements and where they were intended to be used.
The Government decree in the 1950s to small engine manufacturers was that all manufactured engines develop at least 95% of the decal horsepower after break in. Power loss will decrease 3% for each 1,000 ft. above sea level, and 1% for each 10 degrees F. above the std. temperature of 60 degrees F. Governors to be set at 3,000 rpm. Production engines shipped not broken in must develop 85% of decal horsepower.  A formula Clinton adhered too.
Over the years Clinton colors for Standard engines were Dark Green, Red, White, Yellow and Gray. The colors for the 800 OEM accounts included many different shades of a standard color, I.E. 6 different shade of red,  4 shades of white, etc, etc. In all the years of production in Iowa an OEM account was never painted a wrong color.
In 1960 Clinton along with the Clevelite Corp. developed a revolutionary new ignition system, called “Dyna Spark” utilizing the Piezoelectric concept. This was a fore runner of today’s solid state ignition systems, no points or condenser. Clinton decided to put the unit on the commercial engine Clint alloy 407 series. Proto typing was done and the unit performed to engineering standards. Last minute cost increases to Clinton were not acceptable so the project was canceled. 5 engines of the proto type run were not returned to Clinton. Today there is only one known engine in the hands of a collector.
Congress in 1962 decreed that a device is needed on all rotary mowers that give the operator the ability to stop the blade prior to hitting an object. The mower industry lobbied and failed to defeat the measure at that point in time. Clinton in 1963 introduced its version of a “Touch “n Stop” that allowed to operator the requested option. Congress had second thoughts and killed the idea and Clinton never produced this model variation.

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