Rumely Oil Pull

Courtesy of H. R. Stonerook, Waterside, Pennsylvania 16690

H. R. Stonerook

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Star Rte. 2, Gunnison, Colorado 81230

Some of you have been speculating on the number of engine makes. I have a list of Gas, Gasoline and Oil engine Manufacturers of 1906 listing 542. Many of these companies made more than one make engine and many small machine shops and foundries are not listed. A total list today, 61 years later, would be astounding.

Kitty writes that John D. Benner, Jr., 313 Ruby St., Lancaster, Pa., would like some information on Maytag engines. Since I've been preparing some material on two-stroke cycle engines, I'll put it all together. I haven't been able to locate an instruction book on Maytag, so I'll have to generalize until I do and will pass along the information when I receive it.

The first model Maytag engine I am acquainted with was a vertical, single cylinder, two-cycle with spark plug ignition supplied power by a separate high-tension coil and battery connected with an electrical contact on the crankshaft. Later models were horizontal with magneto ignition built into the flywheel and included a two-cylinder model. The last gas-powered Maytag Washing machines I saw used a 4-cycle Briggs and Stratton engine.

Maytag engines were air cooled with blades in the flywheel supplying an airflow around the finned cylinder. Since these engines were small and relatively slow speed, they were low powered but adequate to power the Maytag washing machine and smaller jobs.

With 2-stroke cycle (for brevity I'll refer to these as 2-cycle) engines, the intake and exhaust strokes are eliminated. Every inward stroke is a power stroke and every outward stroke is a compression stroke.

This is made possible in most 2-cycle engines by using both ends of the piston action.

The air-fuel mixture is first drawn into the crankcase on the outward stroke and compressed there on the inward stroke. The piston, near the lower end of its stroke passes an opening which is the exhaust port, allowing most of the exhaust gases to be expelled. Next it passes another port, opposite, which is connected to the crankcase. The compressed fuel-air mixture in the crankcase then rushes into the cylinder, strikes a baffle on top of the piston which diverts it toward the top of the cylinder, further forcing out the exhaust gases as the piston starts outward. Some turbulence in the cylinder causes some of the exhaust to remain and some of the intake to be lost, preventing the engine having the power output efficiency of the 4-cycle. Further power is lost compressing the crankcase charge. However, twice as many power strokes are obtained. A lighter flywheel can be used and elimination of valves and associated moving parts makes a simpler, lighter engine. An automatic valve is usually used in conjunction with the fuel-air mixer to allow the mixture into the crankcase and prevent its escape. Early engines used a pop-pet-type valve and more modern ones a reed-type.

The Maytag engine used a hole through one main bearing journal con-meeting a circuit between the mixer and crankcase to perform the valve action.

The crankcase must be air-tight in a 2-cycle engine. If air is drawn in anyplace other than through the fuel mixer it won't get sufficient fuel. If it loses the mixture through a leak it won't have pressure to force the mixture into the cylinder. This can especially cause hard starting since at cranking speed a leak has more time to interfere with the fuel-air function.

The main source of leaks are worn main bearings since the fuel-air mix traveled through one of them. Maytag was particularly affected by loose main bearings since the fuel-air mix traveled through one of them.

With most 2-cycle engines the lubricating oil is mixed with the fuel and enters the crankcase with the fuel-air mix. As the fuel is vaporized the internal parts are bathed in a mist of oil. Most of the oil is subsequently lost into the cylinder and burned or exhausted. Operation of larger 2-cycle engines is costly, especially for long periods of operation.

Thus most 2-cycle types are limited to small sizes or are of different design. (One large type uses a conventional oil reservoir in the crankcase, receives air from an external pump and has the fuel injected direct into the cylinder).

The oil used for mixing with gasoline should be non-detergent oil such as outboard motor oil, not just a cheap oil. The gasoline should be non-leaded. Detergents and lead tend to accumulate in hard deposits around port-type valves and cause scoring and wear of the piston and rings.

Maytag furnished two measuring cans. A small one measured oil into the larger one, up to a stamped mark, then gas was added to another mark near the top. Mix well. The mixture for Maytag figured one part oil to 12 parts gasoline.

On Maytag a small hand-valve controlled the fuel flow from a small tank under the engine. Clockwise shut off the fuel and approx. one-half turn counterclockwise was maximum opening. Adjustment should be made for best operation of the engine, usually between one-fourth and one-half open. I'll take up ignition in the next Issue.

These are pictures of an Oil Pull I built last summer, using an Allis-Chalmers W. C. rear axle frame and transmission and using a Witte 12 hp. oil engine. It is driven through belt pulley. I had to move transmission back 11 inches to make room for this size engine and welded 10 inches to front of frame.

I used ? ton Ford front axle. A Ford radious rod, 18' saw mill pulley on engine and a Silver King driven pulley. Exhaust piped in smoke stack.

 I put plate over cooking hopper and ran pipe in smoke, stack. Exhaust is below steam pipe. When running, looks and sounds like Rumely Oil Pull. I had a Rumely Oil Pull 20-35 for several years and sold it last year. I had it down to Williams Grove several years-had this one down last year and to the Pioner Power Reunion at Roaring Springs. It will run 4-5 miles an hour on 4th gear. I'll try and have more stories and pictures later as I have 10 gas engines counting this Witte - from 1 - 12 hp. I have a beauty of a 9 hp. Galloway on factory horse truck. I put it on rubber to tow back of this Oil Pull in parades.

I have been playing with engines since I was 13 and we bought our first one in 1909, a 6 hp. International like the one on Page 38 in May-June Gem. I am 71 and love to hear the one lunger bark. Had the Witte running today.