MTFCA Forum

Does anyone out there collect spark plugs? I tried contacting a club, but everything was written in German! I have what appears to be a nos porcelain.
It says Mosler Spit Fire, Patented, Made in France.

If someone here doesn't express interest, contact these folks. They have a presence on Facebook as well.

http://www.spcoa.net/

https://wrenchwiki.com/mosler-spark-plug/

If you do a search on the forum for "spark plug" I''m pretty sure I'll turn up there someplace. I've been collecting plugs for years and have posted many times about them including photos of examples from my collection.

The Moslers were a well-known early plug, in fact some were supplied to Ford prior to and in the early years of the T. This one from my collection is actually stamped in the steel "Ford Motor Company, Detroit Mich." Another photo of a Mosler from my collection is marked "Made in France" on the porcelain. What you probably have is one of the replacement porcelain cores, or if it appears used, it may have been removed from it's steel and brass shell.

In the early 1900s, French made porcelain was far superior to anything else and was used in plugs distributed world-wide. Moslers were produced and sold by the A.R Mosler Company in New York starting around 1902. It's interesting that the porcelain insulators in their earliest plugs were reversible. The plugs were advertised as having "a double life." They used insulators made in France, importing them in large quantities until the mid 1900s, when they began using American made porcelain. They made a tremendous variety of plugs over the years. They were very good plugs and were quite popular in their day.

Mosler acquired the Canfield Patent and aggressively pursed anyone who infringed. That patent was a design patent granted in 1898 and it introduced a larger surface area surrounding the center electrode. That proved effective in helping to minimize short-circuiting due to carbon and oil deposits. That's why the Moslers have the "Patent 1898" date stamped on them. It's not the date the plug was made as is commonly believed.

Eventually, the patent was found to be in the public domain as so many manufacturers were utilizing it. The story is much more complicated than that but tor simplicity sake here that's the "thumbnail" sketch.

Mosler eventually went out of business for various reasons including brand saturation with multiple names and type numbers that caused confusion in the market place. While they tried to make a plug for everything it was very confusing to the consumers who were accustomed to buying pugs only by thread size and length. They spent vast sums defending their patents and got little return, and in turn were sued by others-especially Champion who won not only an initial law-suit but later an injunction on their production of a plug for the Model T ford that too closely resembled the well known Champion X.

The Moslers are not difficult to find and are an attractive plug, popular with collectors. Many of them wee nicely nickle plated.
I'm sure this is much more than you wanted to know - but as they say on TV -"but wait...there is more."
I did a seminar at the AACA Annual Convention last year on "The History of the Spark Plug" and included information on the history of Mosler. There was a lot more interest in that history than I thought there would be. Still, much has been lost over the years and nothing is known of the vast majority of the thousands of different plug brands that have come and gone.

Terry

I have a couple of Liberty Spitfire plugs. They actually do spit fire.

As mentioned here’s the main one I think. http://www.spcoa.net/

Here's a link to a number of more images & associated links
https://www.google.com/search?q=Mosler+ ... 9&dpr=1.13 --
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The "spitfire" plugs have a special design that collects some of the incoming fuel/air charge within a confined space in the lower plug body. When the spark is applied, this charge is ignited and rapidly expands, causing jets of flame to spew out of the confined space and into the combustion chamber. This effect probably gives some degree of self-cleaning and probably gives more reliable ignition in low speed engines with low compression and large volume combustion chambers. The design fell out of favor as engine speeds and compression increased. Ford dismissed all such innovation and insisted that the Ford recommended plugs gave the best results. To observe the spitfire effect, go outdoors and dip the cylinder end of a spitfire plug in gasoline, then immediately apply a spark. You should see a jet or jets of flame erupt an inch or so from the plug. Be careful around gasoline. An amount sufficent to wet the end of the plug is all that is needed.

I obtained a NOS Mosler porcelain in a pile of parts. It's made in France.