Upon viewing the engine of any fuel dragster, funny car or altered, one of the most obvious items is the fuel pump. Unfortunately, acceptable kit pieces are pretty much non-existent. Altered States makes a very nice resin piece, but, if you’d like to try your hand at scratchbuilding, a mechanical fuel pump is a good project to start with--they're easy, and it shouldn't take more than an hour to complete. They are created from several simple components combined to make a noteworthy piece. Here we construct an Enderle 110 style pump. A Hilborn pump differs slightly, but the same process can be used to create one. Follow along and you, too can...
By Daniel Himmel

At right are the components needed to create the pump. They are:

1) Pump Body--.125” length of .125” diameter tubing, or rod, drilled through .063”.
2) Drive Tube--.063” rod .5”-.75” in length
3) Fuel inlet/outlet--.060” diameter rod, drilled to accept locator pins for the fuel lines.
4) Cover Bolt Bosses--.040” half-round, cut to .040” in length (need 6).
5) Front Cover--.010” disc; diameter explained in text, below.
6) Center Cap--.063” disc, approximately .005” thick.
7) Cover and Mounting Bolts--.030” hex stock, sliced thin and uniformly (need 10).
8) Mounting Flange--.010”X.125” disc drilled .063”

First, install the drive tube into the pump body. Once it’s set, drill through the pump body to accept the inlet/outlet tube. Be careful here to avoid crushing the pump, and, to assure that you’re drilling straight through the center. Also note that the drive tube length will vary, depending on required length. It will be longer on blown engines (to clear the belt) and shorter on straight injected engines.
Now, cement the half-round segments around the perimeter of the pump body. Take care that they are equally spaced, and that they straddle the inlet/outlet hole. Liberal application of cement will allow the segments to “settle in” to the body, helping to hide the seams.
     If you don’t have .040” half-round, cut a short length of .040” rod, and drag it across a sheet of fine abrasive paper to flatten it on one side to create the boss material.
Slide the inlet/outlet tube through the pump body and cement it in place.
Begin installation of the mounting flange by drilling a .063” hole through the camshaft hole in the front cover into, and through the front of the engine block. Slide the pump drive into the hole until the pump is the proper distance from the front of the engine. Be sure there’s enough distance to clear the blower belt. Mark the shaft where it meets the front cover. Slip the flange onto the drive shaft, and place the shaft in a pinvise, leaving .010”of the shaft exposed between the mark on the shaft, and the face of the pinvise. Slide the flange against the pinvise, and cement it in place. Be sure the flange is straight on the shaft. Now’s a good time to paint all the bolt heads. I like to use a matte brass-colored paint for the contrast it provides. Paint the pump/shaft/flange assembly a dull, aluminum color (Walmart carries a line of Plasticoat bottles and sprays; their aluminum and brass are identical to Pactra’s old flats).
Cement four of the bolt heads equally around the flange, positioned as shown. At this time, cement the center cap to the pump cover.
Paint the pump cover a slightly brighter silver than the pump/shaft assembly. Testor’s aluminum metalizer is a good choice. Install a tab for the fuel shutoff cable--study your reference for the exact design, as they are often hand-fabricated, thus, there are many different styles. This illustration shows a simple “L” tab configuration made from .005” brass sheet. Now install the remaining bolt heads.
Mount the front cover to the pump body. Be sure that the bolt heads center over the bosses on the pump body. Install the pump, and you’re done!
The pump in my Terrible Too SLM diorama submission was built using the method outlined above. Virtually any part can be easily replicated by copying its simplest shapes in scale, and  combining those shapes to create a complete, complex assembly like the fuel pump shown on this page. Scratchbuilding isn’t a black art. Stretch those scratchbuilding legs, and discover another exciting aspect of the scale modeling hobby!

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