Fig. 15: Thumb screw type speed changer
This is the second and final part of an article written by
Wayne Grenning of 318 Summit Street, Boonville, New York, 13309.
The article was begun on page 4 of the September/October 1982 issue
of GEM. Part One of the article covered the
development of the 1 HP IHC 'M' engine; this part goes on
to explore the development of the 3, 6 and 10 HP models.
3 Horsepower: 1918
Production of the 3 horsepower type 'M' engines began in
1918 and continued through the Great Depression until 1937 (see
figure 17). The very first few 3 horsepower 'M's used only
one pushrod. Both exhaust valve and ignitor were operated by this
single pushrod, which was quickly discontinued. The two push rod
version was then adopted. From 1918 to approximately 1922, the 3
horsepower unit was built with the type 'L' low tension
rotary gear driven magneto (see figures 4 and 5 in S/O 82 GEM). It
was the same in every way as the magneto used on the 1 horsepower
'M' except for the number of teeth on the gear. Location of
the drive gear was also within the crankcase. The engine was only
offered in the kerosene version unlike the 1 horsepower.
Carburation consisted of the two needle valve unit, one for fuel on
the right and water on the left. It operated almost in the same way
as the 1 horsepower engine.
As with the 1 horsepower 'M' the 3 horsepower underwent
similar changes. International offered the high tension American
Bosch magneto, but only 1000 of these were built with this option
between the years 1923 and 1932. White metal was used instead of
cast iron for the fuel pump and the needle valve heads.
A new carburetor was added. It featured three needle valves, a
take apart body, and individual chamber drains for kerosene,
gasoline and water (see figures 8 and 9 in S/O 82 GEM).
The crank-case hatch was changed from the butterfly fastener to
four machine bolts.
The Wico type 'EK' magneto was offered with the engine
in addition to the American Bosch type 'S' (see figures 12,
13 and 14 in S/O 82 GEM). At the same time the
International Harvester type 'L' rotary low tension magneto
and ignitor were retired. The spark plug was positioned on the
governor side of the head and to the left of the intake valve. From
the years 1918 to 1922 a total of 75,310 3 horsepower engines were
built with the type 'L' magneto. Later, 27,885 engines were
built with either the Wico EK or the American Bosch 'S'. In
1937 the list price was $95.00 and only 48 units were built. A
total of 103,195 3 horsepower engines were manufactured in 19 years
6 Horsepower: 1918
International Harvester offered the 6 horsepower 'M' to
the public in 1918. The developments and design of this engine
paralleled the 3 horsepower unit except for the following items: 1)
The magneto was a low tension International Harvester type
'R' rotary gear driven unit, (see figures 18 and 19 The
ignitor was the same as the 3 and 1 horsepower units. They were in
fact interchangeable) 2) The Flywheels had dogs to which a flat
pulley or clutch was bolted. 3) The head was always water
Page: 1 | 2
| Next >>