A Model Reid, 'power' and pump Jacks


| December/January 1993



Clerk cycle engine

7574 South 74 Street, Franklin, Wisconsin 53132

Reid engines had fascinated me for several years, because of their extra charging cylinder and odd configuration. The Pennsylvania and West Virginia oil fields have also interested me for years, because of their old and varied mechanical equipment that is still operating. That is why every year our family spends one week taking videos of the old wells that are still operating, being powered by Reid and other makes of engines. Some wells have one engine powering one well and may still have the derrick in place. Some other wells have a central powerhouse, where the engine is belted to what is called a 'power.' This is a gear reducer with one or more eccentric rings mounted on it. Several wells (maybe 25) are attached to these eccentrics with steel rods transmitting the pulling power. The rod lines fan off from the central power like spokes on a wheel, with the wells being up to a mile away. The rod lines would run up and down hills, across rivers, under roads (through pipes) and up and over other roads through all kinds of mechanical linkages. At the end of each rod line is a pump jack. Some are 'low budget,' made of wood or old pipe, but most are factory built of steel channel.

The Reid gas engine was designed around the Clerk cycle engine designed by Dugald Clerk in England. The Reid was the only American engine built to use this design with the separate charging cylinder. The Reid was built in Oil City, Pennsylvania, and was built especially for oil well use. Most Reid engines use a hot tube ignition, and are fueled from the natural gas at the well head. Joseph Reid was issued his patent in 1898 and built these two cycle engines in sizes from 4 to 40 horsepower. The 15 and 20 horse engines were the most popular.

I had to have a model Reid, so I purchased a set of castings from Burns & Horner Engine Company (they advertise in the classified section of GEM). I knew that the model was large. It is a quarter scale model of the 6 HP Reid and is available in right-hand or left-hand configurations. The castings are clean and of nice quality, but one had better have the use of a large lathe and at least a Bridgeport milling machine to machine the big pieces. The iron machined well, and I found no hard spots. The two cylinder bores were kept parallel by the use of a fixture that was bolted to a lathe face plate. I bored the cylinders to within .004' of finish size and then had the two bores professionally honed to size. As the bore is the most important part of the engine, the precision honed bore is well worth the additional cost.

My being a design engineer is probably one reason for my love of O-ring seals. This kit calls for the main valve body to be sealed to the cylinder in two places with copper rings. I didn't like the copper rings. They are not a positive seal, like an O-ring would be. Also, the valve body, if sealed with O-rings, can be removed and replaced as many times as necessary, with a perfect seal each time. I designed an O-ring seal for the valve body, using two O-rings and also the sealing surface of the mixer valve.

One other change that I subsequently did to both ball check valves was to limit the amount of lift available to each ball by inserting a screw into the casting that is a set distance above each ball, calculated for the area of the seat. This improves operation of the engine.