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					                       Reverse Engineering of a 4-Stroke Engine

         You will be learning about the following items:
          The process of reverse engineering in general,
          How a 4-stroke internal combustion engine works,
          The function of various parts of an internal combustion engine,
          The material and manufacturing processes used for various parts as well as the design
            reasoning behind these choices, and
          Descriptive writing of mechanic devices.

What is Reverse Engineering?
        Reverse engineering is the practice of taking something apart to 1) understand how it works, 2) to
understand how it is made or assembled, and/or 3) figure out how to improve it. For example, when
General Motors launched their Saturn division, they bought several hundred Honda Accords, Toyota
Camrys, and Nissan Stanzas. Naturally, GM engineers stripped many of these cars to pieces in an
attempt to figure out how they were put together, how various things worked, and above all, what lessons
could be learned to help GM engineer their new line of Saturn vehicles. We will be conducting a similar
exercise today, disassembling, inspecting, and then reassembling the a 4-stroke internal combustion

         While this is a fairly simple lab, even for those of you who have never done this sort of work
before, it is important that you follow some guidelines:
         1. Follow the directions of your instructor. The disassembly steps are intentionally coordinated by
               the instructor to aid the discussion throughout the session and to keep the whole class
         2. Take turns with the tools. Those of you that are “old hands” at such work might consider
               letting the others do the work with you there to help them. Feel free to ask the others in your
               group if they have had any previous experience with these things and take the opportunity to
               help them if they haven’t.
         3. Don’t force anything . Several of these parts are rather particular about correct location
               relative to other parts, so pay attention to things as you remove and replace items. When in
               doubt, ask someone. By the way, these are brand new engines; the last ones were pretty bad
               off because a few individuals in the past were outright destructive—please police yourselves.
         4. Print a copy of the table on the following page. You will use this to take notes during the
               reverse engineering process.

         One of the objectives of ME 221 is to develop your understanding of technical writing for
engineering. This assignment is practice in technical writing skills that will be needed when you start
writing lab reports.
         You will be asked to use two figures supplied to you as “supporting material” in your discussion of
the old and new cam designs on these motors. In addition to reinforcing the proper citation of figures and
giving some practical skill in putting the graphics in the text, the objective of assignment is to give you
practice in writing to communicate using both words and graphical material—photographs in this case.
         Your text must be 300 words or less.
         Pictures and further instructions will be posted. You will turn in the 1 page result and attach the
table on the next page—filled in, of course, to show you paid attention in lab.

  This directive includes no prying with screw drivers, hammering with wrenches, and other “irregular” practices with
tools. The truth be told, you can at times do a lot with limited tools in desperate circumstances, but that is not the
case in this lab.

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       Table 1: Observations of parts of a 4-stroke internal combustion engine.
Part        Functions             Material    How can you tell?                   How can you tell?

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