• EMD Model 184A Diesel Engine

  • Discussion of Electro-Motive locomotive products and technology, past and present. Official web site can be found here: http://www.emdiesels.com/.
Discussion of Electro-Motive locomotive products and technology, past and present. Official web site can be found here: http://www.emdiesels.com/.

Moderator: GOLDEN-ARM

  by RAS
I am curious about the EMD Model 184A diesel engine built for the USN in World War Two. Would anybody who has worked on them or run them like to offer any comments? Do any still exist? I realize this is very obscure but it might be of interest to a few people.

  by mxdata
The EMD Model 184A Diesel Engines for the USN subchaser program were built in the La Grange plant early in World War Two, in a portion of the factory which had been erected just for this program and was afterwards known as the "Navy Building". A product of Kettering's brilliant design team, the engine occupied just slightly more space than a modern kitchen refrigerator (the engine stood on end) and produced 1200 (yes, one thousand two hundred) horsepower. The designers pushed both the materials and the existing technology to the absolute limits in the production of these machines, which were very short lived between overhauls. They met the needs for which they were built, but left the scene quickly after the war ended. I know of only one that exists today, in the Southeastern US. It is complete and intact, but is privately owned, so I will not identify the owner here. Anyone knowing of any additional surviving engines, please add on to this discussion!

Compared with the similar HP range Packard M2500 PT boat engine (1350 to 1500 HP, a gasoline engine), only about 1/8th as many 184A diesel engines were built. Consequently the manuals for the 184A engines were printed in very small quantity and they are among the rarest of EMD publications. Only one was issued per subchaser, so total distribution was about half as many as the total number of engines built since each vessel had two engines. There was a beautiful operators manual with an embossed color cover similar in style to the early FT locomotive operators manuals, and there was also a large hard cover combined operators and maintenance manual which had a number of superbly detailed fold out drawings and exquisite cutaway color plates of the engine from above and the side. In almost four decades in the diesel engine business I have seen exactly ONE of each of them. I cannot guess what one would sell for in the collector market, as I have never seen one offered for sale. Both manuals clearly identify the Electro-Motive Division of General Motors in La Grange, Illinois as the builder of the engine, not Cleveland Diesel Engine Division (the former Winton Engine) or GM Diesel (which became Detroit Diesel after the war).

Any time you read a book or an article on the history of Electro-Motive you can get a pretty good idea whether the author has really done their homework by looking to see whether the EMD Model 184A is included in the list of engines they built.

  by Phil Hom
EMD published a small hard cover picture book about the EMD engines that the Navy used in WWII. Most of the text in this undated book is on the "pancake" engine as well as the 567 as designed for US Navy use. A color photo of workers working on the engine as well a a few photos of the "Navy" building at the EMD plant.

I got mine from ebay.

  by mxdata
Yes Phil, a friend who worked at the plant all through the war told me back in the 1970s that the book which was issued to employees came out a couple months before the end of the war, early in 1945. Judging by the choice of words used to describe the enemy, and the wording of the General Manager's transmittal letter which was printed in the front of the book, it certainly sounded like the war was still in progress when it was issued. The production chart cuts off in the middle of 1944 and the factory additions which opened in 1944 are illustrated.

Cleveland Diesel and Detroit Diesel also did similar internal books which were issued to employees to commemorate their part in the war effort. They may have borrowed this idea from the "cruise books" which were issued on Navy vessels, since all three divisions were heavily involved with production for the USN. One GM Division war book I would really like to see, if they did one, was Pontiac Motor Division, as they built both the 20mm Oerlikon and 40mm Bofors anti-aircraft guns during the war.

Judging by the EMD General Manager's letter, which mentions Detroit Diesel specifically by that name, it would appear that the comment I made earlier about them adopting the name after the war ended is incorrect, even though what I wrote agrees with the company history that is posted on the Detroit Diesel website. I should have noticed this earlier, as I have some wartime manuals for 71 series engines and I see that they were issued under the Detroit Diesel name. I believe GM Diesel Power was the correct name for the marine and industrial marketing organization at that time.
  by boeing377
In the mid 1960s I rode from SF CA to Half Moon Bay CA and back on a converted USN WW2 wooden 110 ft. subchaser named the Nevada Lady. It was converted into a yacht. It had two of these odd (EMD Model 184A?) pancake diesel engines which were run at constant speed and the props had variable pitch. As recall they were mounted with the cylinders parallel to the ocean and drove the prop shaft through a right angle gearbox. They looked a bit like radial aircraft engines. The engines very reliable according to the boat's engineer. He ran the boat easy which may account for their longevity. I think our top speed was about 14 knots.

  by RickRackstop
Development of the "pancake diesel" was continued after the war by Cleveland Diesel not EMD. The Tang class submarines had this engine installed mostly because of the high power for such a small volume. Since the axis of the crankshaft was vertical the generator was mounted underneath the engine. In Norman Friedman's book on the design history of US submarines he says that the engines were hard to work on and leaked oil into the generator. In 1957 the Tang went into the shipyard and the engine-generators were replaced with Fairbanks Morse 10 cylinder OP's. This necessitated the hull be cut apart and a 9 foot plug installed to accommodate the new engines. If these engines were used in commercial vessels they were probably war surplus. Diesel Parts in the Bronx (NYC) and Hatch & Kirk in Seattle probably have some parts somewhere around back in the warehouse. The navy dumped new parts and complete new engines after the war at scrap metal prices and later had to buy some back at a lot more than they originally paid for them.