A Reader Responds

Associated-United Engines

| August/September 1986

26 Mott Place, Rockaway Boro, 'New Jersey 07866

The following three articles were written in answer to readers and questions which appeared in the Reflections column in the March 1986 issue of GEM. It is hoped that Mr. Mackey's detailed information will be helpful to other readers.

The first two articles deal with the question from Hugh E. Porter, RR 1, Box 274, Dallas City, IL 62330: 'How many models were made of the small Reo and Continental engines, and where might we locate manuals for same?'

Reo Engines

The Reo 45° bank 1-cylinder engine (cast iron) was made from approximately 1947 to 1958. It departed radically from the accepted designs of the times in which it was built. It is the only small 1-cylinder 4-cycle engine that runs counterclockwise. The cam and valve arrangement was unique (see diagram) and the camshaft was also the sole power takeoff point except for one example that had an extra reduction built in.

These small but strong engines were made with many variations. Some were minor, like a different carburetor or fuel tank. Others were major, such as a change in bore and stroke, or the placement of a recoil starter (with a stainless steel pull cord) instead of the standard 'wrap a rope' setup.

There are 3 major 45° engine types. First, the most common, is the 'regular' 45° engine. This engine was mostly put on Reo reel type lawn mowers, called the Reo Royale (early) and the Reo Runabout (later). I own about 8 of these engines and no two are exactly alike. The later engines almost always had the recoil starter. The second type was still a 45° bank engine, but had an extra gear reduction built into the timing case. This produced a 7 to 1 ratio at the output shaft. These were used on a 2 wheeled garden tractor built by Reo. The third type was again a 45° engine, but this series was placed on its side to power a rotary lawnmower. This mower was also built by Reo. I do not have specific information on the third model as I do not own one (yet); however they were only built during the last two years of the 45° engine's production. The crankshaft was vertical in this model; on all others it was horizontal. I have only seen two examples of this type engine.


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