1918 McCormick-Deering Model M engine. This one is an earlier model with the understrike igniter.

This page is about the overhaul of an International Harvester 1-1/2 horsepower Model M engine.  The Model M line of engines was manufactured between 1917 and 1937, and came in 1-1/2, 3, 6 and 10 horsepower sizes.  The serial number for this 1-1/2 horsepower engine indicates that it was built in early 1918.  This type of engine did not have a sparkplug, but used an ignitor instead.  The ignitor had to be “tripped” by some mechanical linkage, and since these earlier McCormick engines used a linkage that tripped them by striking a mechanism on the bottom side of the ignitor, they were called “understrike” type engines.  The understrike Model M engines were only built between 1917 and early 1919.

This is a real piece of history.  It is hard to imagine that during the time this engine was built, WWI was being fought with American GIs already on the Western Front.  Woodrow Wilson was President, and the Panama Canal had only been open for about 4 years.  The population in the United States was just 103 million in1918, that also being the only year that our population decreased in the last 100 years.  The federal budget was 12.68 billion and a first class postage stamp cost 3 cents.  And Internation Harvester, the company that grew from the merger of the McCormick Harvesting Machine Company and Deering Harvester Company in 1902, sold this engine to some farmer to make his work easier.  I’m not sure what it cost back then but it was probably somewhere around $30.  Keep in mind that the average annual income in 1918 was around $1,500.