This is a new column designed to familiarize those not acquainted with the Mechanics of Diesel Locomotives, and their mechanics. We'll be discussing Engines, Braking, Electronics, how HEP (Head End Power 480 Volt Power, used for Passenger car Power) is created among the different types of Locomotives used. Some of you will no doubt question this column, especially if you too are involved in working on Locomotives. I have 32 years of experience, first with Union Pacific, and now with Amtrak. True I don't have all the answers, but will discuss this column with other Mechanics, who may be more familiar with different systems that I may not be familiar with. For this first article I will discuss rpm. Most of you probably have Tachometers in your cars, which shows revolutions per minute. Now take a guess of how fast you think a F-40 EMD (Electro Motive Division of General Motors) engine turns per minute in Run 8, which is full throttle? Maybe 4000 rpm? as maybe your Car might run at 90 MPH. Guess again! In run 8 a 3000 HP 16 cylinder Engine turns only at around 1000 RPM. In your car this would only be a fast idle! So why does it make so much noise? For one reason EMD engines used in F-40s are a 2 Cycle design, just like your gas powered blowers, you use to clean up lawn trimmings around your yard. 2 Cycle Engines fire on every revolution, making then fire twice as many times as your standard Automobile engine does. On the other hand General Electric Locomotives are a 4 stroke design similiar to your car Engine. Still they sound like their turning faster that 1000 RPM though. This may be due to the large number of cylinders envolved, usually 12 or 16 cylinders.
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