HISTORY OF THE EMD 645 AND
The Electro-Motive 645 and 710 series
diesels are used in many modern tugs as well as a wide variety of
other marine propulsion and generating applications. The 645 series
engine has a cylinder bore of 9-1/16 inches and a stroke of 10 inches,
and was built in 8, 12, and 16 cylinder "normally aspirated"
(roots blower) configurations and in 8, 12, 16, and 20 cylinder
turbocharged versions. The 710 series engine also has 9-1/16 inch
bore, but with 11 inch stroke, and was introduced in the 1980s as
an enhanced fuel economy and reduced emissions engine. The 710 is
only built in turbocharged versions, with 8, 12, 16, or 20 cylinders,
and has been produced with mechanically controlled fuel injection
as well as electronic injection systems. Both engine series were
in production simultaneously from 1983 through the late 1990s, the
645 series has now been discontinued.
The 645 and 710 series are the successors
to the EMD 567 series engines, first built in 1938, which were developed
by a team of talented design engineers at the GM Research Laboratories
under the direction of Charles F. (Boss) Kettering. The 567 engines
were used in many railroad applications and are still quite common
in marine service. They all have an 8-1/2 inch cylinder bore with
10 inch stroke. The 567 series underwent a major design change in
1953 under the direction of Eugene Kettering ("Boss" Kettering's
son) that strengthened the engine crankcase allowing higher power
outputs, while still maintaining parts interchangability with the
earlier engines. The 645 engine introduced a greatly strengthened
crankcase along with a bore increase to 9-1/16 inches. The 567 crankcase
went out of production following the introduction of the 645 series
engines in 1966, although a few late 567's were built in 645 crankcases
to satisfy the military's "proven product" requirement
for diesel engines.
Electro-Motive dates back to the
1920s, when it was established as a designer of gas-electric railroad
passenger cars in Cleveland, Ohio. It was acquired by General Motors
in 1930 along with the neighboring Winton Engine Company. It became
the Electro-Motive Division of General Motors (EMD), a major builder
of diesel locomotives and marine engines. Electro-Motive is now
owned by Progress Rail, a subsidiary of Caterpillar, and EMD trademarks
and copyrights are now the property of Caterpillar.
Above: A 16-645 Marine Engine at La Grange in the
1960s. Notice the deep sump oil pan required on most marine installations
to allow for the rolling of the vessel when operating in heavy seas.
Above: Following its use in testing, the First EMD
710 Series Engine was painted in Pontiac GTO metallic blue and was
used for many years as a show engine. When it was on display at
boat shows the oil pan was usually not shown, since it really was
a locomotive engine, not a marine engine, and did not have a deep
sump oil pan.
Above: Electro-Motive had a curious history in the
marine industry. The EMD engines were originally designed for railroad
locomotive use, while Cleveland Diesel Division of GM built the
marine diesel engines. At the beginning of World War Two, there
was a shortage of marine engine building capacity, and EMD engines
were installed in three U.S. Navy fleet tugs. The installation was
highly successful, and resulted in their being awarded the contract
for more than 2400 engines for U.S. Navy LST vessels (as shown in
the background above). In the postwar years Electro-Motive took
market share away from Cleveland Diesel and eventually absorbed
them. Cleveland Diesel rights and trademarks were sold by GM to
Hatch and Kirk of Seattle, Washington in 1977.
Above: An EMD 20-cylinder 645 series engine is prepared
for installation at a shipyard. Sitting next to the engine is the
Falk reverse reduction gear.
Above: Two EMD 20 cylinder 645 series marine engines
are show in the engine room of a vessel that has a combining reverse
reduction gear, both engines drive one propeller shaft. The 20-645
was a very popular marine engine for installation in new construction
vessels from its introduction in 1966 through the release of the
subsequent EMD 710 series engines in the 1980s.