Champion X was usually the plug supplied on a Model T, but Ford used a few other brands, and there were oodles of aftermarket Model T plugs.
This was one of the brands Ford used. I've been picking up odd plugs at auctions and swap meets, and decided to try some of these in a car. Unfortunately not one of them would fire. Oh well, back to good ol' X.
Splitdorfs. Cool looking and highly prized by spark plug collectors and a few motorcycle collectors I know, but maybe best fitted for the display shelf?
That's normal with Splitdorfs plugs which are made of mica. They worked well when new but didn't last long.
The good thing about mica plugs is that they were much stronger (less likely to break) than early Champion X plugs which were not sillimanite. You can ID a sillimanite X by the two ribs at the top; the older straight sided X is not sillimanite.
Steve, your recent post complaining about a number of X plugs breaking on you over the last year confirms this ad! :
I've been taking the roadster out for test runs today, and the X plugs are giving me fits. Two broken insulators and one that came loose even with a new washer. This is a 1915, so I've been using the straight sides. Later I'll try the ribbed plugs and see if they do any better. But for now I'm going to put in a set of Autolites just so I can go for a test drive without a spark plug going south on me.
I wonder if baking them in a oven would help "rejuvenate " them. I think mica is somewhat porous and over the years they may have gotten wet. No garrantee, but if they were mine I would try it. Nothing to lose. I'd probably give them a hour or so at about 300F. Try one please
Hey, the guy fixing the T in the ad above even has a shop coat and cap exactly like Steve!
What Les suggested is worth trying; I fear though oil and carbon has seeped into the mica not water.
This is where all sillimanite X plugs began; be great to drive a T there to visit:
These Splitdorf plugs ran great in my speedster.
Guess all cars are different. My 1906 Queen ran "okay" on Champion X plugs. I put a set of Splitdorf green jackets (top photo) and it runs great and starts easier. Go figure....
My Maxwell came with a set of Splitdorfs that spent the better part of 50 years outside and were so badly rusted I figured they were only good for display in a spark plug collection. Imagine my surprise when they worked perfectly on my first start. I'm still running them as they function perfectly, just look a little "used". Based on how expensive they are and how well they sell I'd say the bad reputation isn't deserved.
Your mileage may vary.
The mica Splitdorfs (and others) were made of thin wafers of mica stacked and compressed together. The problem is that oil and crud will easily get impregnated in between the layers and cause the plugs to foul or short circuit. I once tried to find a set for a good friend and went through dozens of them before we found some that fired under compression. A lot of them would spark nicely outside of an engine, but I have a plug tester than has a compressed air fitting on it and that helped us quickly sort though them. They were good plugs but once they started fouling, time to replace.
Any two piece plug will break an insulator easily if you crank down too tight on the packing gland nut, or get the insulator a little off kilter when putting it all back together.
The two ads posted by Constantine on the SPLITDORF plugs are very interesting to me. My research says that the SPLITDORF plug was used in the 09-10 fords, then Ford went to the smooth side Champion X plug in 1911 up through the teens and maybe even later.
I had no idea that the SPLITDORF plug was used later.
Good to see you at vineland NJ Peter. Too bad the brass got wet, but we survived! Splitdorf did supply plugs for the earliest Ts but by 1911 Champions came in them from the factory. Lots of companies made plugs for the Ts and continued to do so long after the 1927 finish. Heck, they do to this day!
My Sept 1921 part book also lists Bethlehem, part number 5200, spark plugs along with Champion, part number 5201. The Bethlehem's were 15 cents cheaper then the Champion's. Any one ever see one of those?
Peter, the two ads I posted above don't say that SPLITDORF plugs are factory fitted to Fords; they suggest that (which is no accident), but do not say that. I know that Champion took legal action against a least one other spark plug maker for misleading advertising.
By the way I believe that SPLITDORF was taken over at some stage by EDISON. "Edison-Splitdorf" branded plugs do exist.
Mark, I can confirm that Bethlehem plugs were used by Ford. Ford purchased 500,000 plugs from them in the early 1920s. Does Bruce McCalley's book note this?
"Soot Proof" plugs were also used on Fords in the 1909-11 period. Some discussion in this thread: http://www.mtfca.com/discus/messages/29/48808.html?1203951468
Mosler plugs were factory supplied by Ford from about 1910 - 1914.
I've seen the Bethlehem plugs, and may even have one somewhere. If I knew where I'd post a picture of it.
Dozens of companies made OEM or aftermarket Model T plugs. Some of these have Model T threads and some don't, but most of the ones that don't also came in a Model T size. Trojan, Blue Crown, Ward's, Jordan, and most of these outfits produced Model T plugs.
Thanks Constantine and Steve.
I was pretty sure I had some of these. It just took me awhile to find them.