IHC-TYPE 'M'


| September/October 1982



Governor and throttle assembly

Fig. 1: Governor and throttle assembly

Wayne Grenning of 318 Summit St., Boonville, N.Y. 13309, wrote the following history of the International 'M' engine, which will be continued in the Nov./Dec. issue of GEM. Wayne is a freshman at Alfred State College (TV. Y.) where he will major in internal combustion engineering technology. He currently serves on the board of directors of the Flywheels & Pulleys engine club at Constable ville, N. Y.

International has been the maker of a vast variety of farm products including: hay balers, combines, plows, ensiligers, potato diggers, and gasoline engines. It is the type 'M' engine that is of concern here. International manufactured many different style engines of all horsepower including among others: the Famous, Tom Thumb, Titan, Mogul, L, LA, LB and the 'M'. A basic description of the construction, characteristics, and chronology of the 'M' series follows.

International engines were manufactured in the 'Milwaukee Works' at Milwaukee, Wisconsin and the McCormick Deering 'M' engines in the 'Deering Works' at Chicago, Illinois. In this article the International Harvester 'M' and the McCormick Deering 'M' are considered the same. They were manufactured between 1917 and 1937.

General Characteristics

The type 'M' was related to the smaller size 1,1?, and 2 horsepower earlier mogul engines. Many similarities between the two types are apparent. The governor, breather, magneto, ignition system, fuel system, enclosed crankcase, and air cooled heads (on 1? and 3 horsepower engine) are all from the same inspiration. It has been said the International 'M' series were modified Moguls with similar parts, lighter construction and higher R.P.M's per horsepower. 1? and 3 horsepower 'M' engines were manufactured with air cooled heads. At the same time the 6 and 10 horsepower models were equipped with water cooled heads because of vast quantities of heat generated under full load.

All 'M' engines were offered as stationary units, on skids or trucks and were painted a satin 'Grass Green' finish except for the rim of the flywheels. Fancy pin striping commonly used on earlier International engines was eliminated on the 'M' series because it helped reduce the price. The 'M' series was distinguished by its one piece enclosed crankcase block, allowing for a clean engine and improved safety. An access hatch on the rear of the crankcase was a necessity for the removal of the connecting rod and piston from the crankshaft. Speed was regulated by a governor which was located on the P.T.O. side of the engine. Two opposed weights were located between spokes of the flywheel. Centrifugal separation of the weights by acceleration of the engine caused a sliding sleeve to move on the flywheel hub. Motion of the sleeve was captured by a rod located on the side of the engine. The other end of the rod was attached to the throttle plate located on the upper part of the cylinder head (see figure 1).

All 'M' engines had cast iron cylinder sleeves (see figure 2). These were of the wet liner type, meaning that the sleeve was the cylinder and cooling liquid was in direct contact with it. Fuel was pumped to the carburetor by means of a piston type fuel pump, operated by motion from the cam eccentric. International designed their 'M' engines with the fuel pump at the same level as the fuel tank. As a result, the pump would always be primed for the next running.