Antique Engine History and A Little Technical Stuff
by Larry Harding
The Gasoline Engine
As you walk around the show grounds and see flywheels turning, hear the popping and see smoke, you may wonder what these things are and what purpose they could have served. You may find it hard to believe, but these are gasoline engines and the forerunners of the high speed, fuel injected, electronic ignition engines used in today's cars, trucks, motorcycles, airplanes and garden equipment. I hope to give you a little history lesson and some insight on this hobby. I dare say that no other invention of our times has touched more lives and changed the course of the world more than the internal combustion engine. There are still people in remote parts of the world that have never seen a cell phone or a computer, but you can bet they have seen an airplane, automobile or something using an engine.
It is hard to picture a time with no cell phones, walkmans, or even electricity, but that is the way it was 200 years ago. All work was done by hand, with the help of animals, water or wind power. In the late 1700's, James Watt had developed a practical steam engine that was able to save a lot of physical work and even led the way to power steamboats and locomotives. The steam engine had its drawbacks though. They were big, cumbersome things and required constant tending to keep them operating, hence the term engineer. You had to build and maintain a fire in the boiler and there was always the chance of a boiler explosion. By the mid 1800's, Otto in Germany, as well as several others had developed crude internal combustion engines. These early engines used city gas, illuminating gas, or producer gas. Gasoline and kerosene fuels came in a little later. Even as crude as these early engines were, they were a lot easier to use than steam engines. By the turn of the century, nearly every city big enough to have an iron foundry and machining facilities had someone building engines. Hundreds, if not thousands, of engine manufacturers sprang up all over the civilized world. These engines were a boon to farmers and industrialists alike. The farmer with the purchase of just one small engine could now run his cream separator, wood saw, butter churn, corn sheller, feed grinder, gristmill and pump water. Everything from small shops to factories could be run on engines now. Here in the South, large heavy oil (semi-diesel) engines were often used to power cotton gins. These engines could usually be started in just a few minutes time, without waiting for a head of steam to build up before operating machinery. The heyday of these heavy single cylinder engines was not to last forever, though. In 1935, the Rural Electrification Administration was created to bring electricity to the countryside lessening the need for engines. Industry was turning to more efficient multicylinder engines as well as electric power. Companies such as Briggs & Stratton and Wisconsin were producing lightweight high speed air cooled engines for portable machinery. Some of the old engines continued to give service for many years to come running wood saws, water pumps and so on. Except for some of the big engines still in use in the oil fields, most have become collectors items. Nothing today sounds quite like a hit & miss popping along at a show. Let's hope these relics of the past will be here for future generations to enjoy.
A Little Technical Stuff . . .
There are two basic categories that antique engines fall into, Throttle Governed or Hit & Miss. All engines have to have some way to maintain a preset operating speed (RPM's - revolutions per minute) under different load conditions. Usually a set of weights that spin outward as speed increases is used, although several other designs may be encountered. With the Throttle engines these flyballs, as the are called, operate a valve called a butterfly in the mixer, or carburetor. As the engine speed increases, the flyballs spin out, closing the butterfly. If the engine slows down due to increased load, the butterfly is opened to compensate and maintain speed. Most "Kerosene" engines use this type of governor, they just have an extra metering screw in the mixer. The engine is started on gasoline, then switched over to kerosene after it is warmed up. Throttle engines run warmer that hit and miss, this helps to vaporize the kerosene. This method is used on engines of today such as lawnmowers, tractors and so on. When running, throttle engines have a steady putt putt putt sound. The Hit & Miss uses flyballs too, but instead of closing a butterfly, the engine stops firing until it slows down to a certain speed, then begins to fire again. This is done in a number of different ways, the most common being a detent lever that moves into place and keeps the exhaust valve from closing. Some oilfield engines do just the opposite, not opening the exhaust valve when the engine is up to speed. Other methods include stopping the fuel or cutting off the ignition to stop the engine from firing. Collectors enjoy tinkering with their engines to see just how long they can get them to go between firing impulses. When running the Hit & Miss will have a putt putt putt sound. As you walk around the show grounds, listen to the engines run and ask the exhibitors a few questions, most will be glad to oblige you and show you what makes things work the way they do. Before long, you will know a throttle engine from a hit & miss just like the experts.