Building an engine model

As a starting point for my van project, I decided to build a model of an engine to familiarize myself with the different pieces and how an engine works. My first thought was to build a very small engine, such as those used in Radio Control (RC) cars or planes that would work like the car-sized ones; but I discarded it after realizing that it is actually harder to build a down-sized engine than a car-sized one, because the tolerances get tighter and you need more precision.

After some searching around the Internet, the options came down to the following:

	One is kit is Smithsonian Motor Works model of a 4-cylinder engine. It is advertised as having 100+ parts, and is powered by a small DC motor and 2 "AA" batteries. Unfortunately, the reviews from Amazon weren't great, as there many claims that some parts aren't manufactured properly and don't really fit together.
	Revell sells a transparent model of a V-8 engine (8 cylinders placed in a V shape), that can be hand cranked to see all the pistons moving. Since my VW bus has a 4-cylinder engine, I discarded this one, and decided to shop around for a closer match to the one I will be working on. This one also costed twice as much ($60) as the other two considered here.
	Haynes, the publisher of many auto repair manuals, also offers a battery-powered 4-cylinder model, very similar to the one above from the Smithsonian, but without the bad reviews (both engines look so similar that one wonders whether they are in fact the same kit under two different brands). I bought this one directly from Haynes for about $30.

The kit comes with all the needed parts (I counted 85 plus a bunch of screws), a small screwdriver, and the instructions booklet. The instructions are detailed and clear. All the parts are correctly numbered and are well manufactured so that all fit together with one another. The only items that you need to provide are two AA batteries, a little bit of vegetable/olive oil to lubricate some parts, and your time to assemble everything together. It took me around four hours to assemble the kit, as I was learning about the role of each component within the engine. If there is one single thing that could be improved is the crappy screwdriver that comes with the kit. I had difficulties screwing the first screw in, until I reached for a slightly bigger screwdriver I had lying around the house. However, the screws are small, and your regular screwdriver won't work, so make sure you get a hold of one the right size (see the last picture below for the comparison of screwdrivers, where the top one is your regular one, the middle one is the one I used, and the bottom one is what comes with the kit).

The cool thing about this engine model is that at the end you have a model that moves the pistons up and down, turns the crankshaft, the rocker shaft, opens and closes the valves, rotates the fan, and lits up four LEDs that simulate the spark plugs firing. You can see a video of the model in action here.

I found out that I learned more about how an engine works going through the process of assembling the kit together, rather than playing with the finished model and watching it move. So if you are curious about what goes on with an internal combustion engine, I suggest you get your own kit and spend some time assembling it. I highly recommend it! Have fun!

01. Back of the box showing contents	02. Contents of the model kit	03. Fitting the pistons on the crankshaft	04. Lower crankcase and cylinder block
05. Upper and lower engine head, and cylinder block	06. Fitting the timing belt	07. Fitting the fan assembly	08. Engine finished
09. Engine finished	10. Screwdriver comparison