Spark-filled History

By Staff
1 / 5
A Vital plug, made in Cleveland, Ohio. This is a rare primer plug with 1/2-inch pipe thread.
2 / 5
A series plug by Sudig Co. made on Dec. 12, 1914, in New York City. This type of plug allows the user to have two plugs in one cylinder.
3 / 5
An extremely rare Blake quick-detach plug. The wooden handle allowed removal without tools. This plug sells for $1,000.
4 / 5
A Rentz intensifier plug. The switch on the left enables the intensifier to be shut off after the engine is started, preventing the coils from melting. It was a wonderful invention, but didn’t last because in 1920 at $2.50 per plug, it cost five times more than other plugs.
5 / 5
The Breech-Block Ignition Co. of Torrington, Conn., made this quick-detach plug, the base of which stays in the engine.

Question: Which product of the internal
combustion age was produced by more than 3,000 manufacturers in the
United States, bearing more than 6,000 brand names and covering
many hundreds of patents? If you answered gas engines, you would be
wrong. The correct answer is spark plugs! Perhaps no other product
associated with the dawn of the gas engine was made with such a
variety of different ideas as those about the “ideal” spark

Driven by the need to prevent fouling of spark plugs by early
gas engines, which consumed oil rapidly, manufacturers tried a vast
array of cleaning schemes such as quick take-apart plugs, which
could be taken apart, cleaned and reassembled by hand, while the
engine was still running! Others tried different designs of
electrodes and insulators to keep the plug from fouling.

Another problem was the difficulty of starting early engines,
especially in cold weather. This resulted in a large variety of
primer-type spark plugs, which allowed priming of the cylinder(s)
with gasoline. And other plugs were designed to assist weak
ignition systems with built-in spark intensifiers. Still other
designs incorporated dual non-grounded electrodes to use in
multiple ignition type engines, (i.e. battery and magneto) or dual
plug systems from one ignition source.

In the years of approximately 1900-1930, it seemed like anyone
who owned a machine shop or factory making products out of metal
wanted to get on the spark plug bandwagon. Ceramic companies such
as Frenchtown Porcelain of Frenchtown, N.J., and others, who were
able to supply the porcelain cores for the many small spark plug
producers, made this easier. They only had to machine the brass or
steel bases and packing nuts and they were in business.

Another way was to use a stack of compressed mica washers and
not risk the easily broken early porcelain. Those of you who have
rebuilt low-tension igniters for gas engines are familiar with

We gas engine and tractor collectors can surely appreciate the
fascination of spark plug collecting, and let’s not forget the
go-alongs such as the signs, advertising, display cabinets,

We have an organization devoted to this hobby called the Spark
Plug Collectors of America, established in 1975. It is an
international organization with members in more than 13 foreign

The SPCOA publishes a 38-page quarterly magazine, The Ignitor.
Membership dues are $25 yearly, U.S. and Canada, and $35
international, which includes a subscription to The Ignitor. Join
us and you will be amazed you waited so long.

Contact Lanny Baron, president of the SPCOA at: 2969 Home St.,
Wantagh, NY 11793; (516) 426-1098.

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