This weekend, I switched out my Motorcraft F11 plugs (gapped around .035) with new old stock Champion-X plugs (factory gapped around .022 or so). I expected vintage magic, but now the car occasionally skips fire when idling and accelerates unevenly. I'm guessing it's the small gap. Problem is, Champion-X plugs don't have normal electrodes and I'm afraid of breaking one off if I use a standard gapping tool on it. What's the secret for gapping a Champion-X plug?
Bob
Secrets none, but my choice is the open type lever gap tool. The kind with the inclined plane don't work for me. Use care, just a tiny bit of leverage is all you need to move the electrode.
Now what to gap is just based on your T, mine has the Z head and I find a gap of .025" + but less than .030" works best.
Ford of course said 'a thin dime' but that gap doesn't do good with my high compression.
The later brass top X's have the outer electrode that you bend in or out to set the gap to the center electrode.
Ford actually "Said" 1/32 of an inch...at least in the service manual.
Here is the source:
1926 Ford Manual
The correct phrase being 'smooth' not thin
1917 Ford Manual
The Ford Service doesn't reference a 'smooth dime' but does state "approximately 1/32."
Ford Service Chapter XXXII paragraph 1002.
1/32" or .031" for gap, but still I like gaps between .025" and .030", seem to always work in my T's
Mine are set at .030" so I'm always curious as to where everyone gets .025" from. Not that it makes any difference...whatever makes your T run its best.
Just curious but was there a problem with the Motorcraft F11 plugs? Were they misfiring or?
There is a lot on the forum about using the original Champion X's and I have a can full of them in various conditions.
When I got my 21 Touring engine rebuilt I decided to use some old used Wizard plugs to get it started instead of using the used and in good shape Champion X's as the Wizard plugs were a matching set.
I must say the old Wizards run great with no problems. Time will tell.
Will I put in a set of the X's? Not as long as the Wizards are working fine.
Yes I know they are not the Original style plugs.
But in the mean time the Wizards are fine. And at they do match.
Maybe the dimes got smoother by 1926.
They sure had a lot more use back then Doug! I have a Dyke's Auto Manual that mentions the 1/32" setting. It also mentions and shows in a picture the worn dime business.
Here it is. Can't tell the manual's age. The first pages are missing but I'm thinking teens.
John,
No, there was nothing wrong with my Motorcraft F11 plugs. The engine seemed real happy with them, but I'm told that Model T's (and other brass era cars) need the hottest plug possible and the Champion-X is reputed to fill that bill. Certainly, when I mention the name of that plug, you can hear the sound of trumpets blowing and angels singing in the background. Heck, I've genuflected a few times, myself.
But seriously; I have noticed a lot of soot on my F11 plugs and I've now got the same black powder on my Champion-X plugs (There! Did you hear it that time?). I'm now figuring the engine may be gargling on too rich a mixture, so I'll tweak & twiddle with leaning it out and see how that goes.
Meanwhile, my car does have a high-compression head and I'm told that they require a smaller spark plug gap than the standard head. I dunno. My old F11's had a big gap and they worked fine. The plot thickens and the story goes on...
William
To answer your post, the .025" is recommended by the plug manufacturer.
Agree with your comment to set the gap to what makes your T run best.
Has anyone ever experimented with plug gap to see what difference it made? What increments did you try? What symptoms did you experience when the gap was too wide and too narrow?
Hal, wider gaps absolutely deliver a hotter spark but in the process impose a much bigger load to the coils.
Too wide a gap contributes to the plug firing high up in the plug, rather than across the gap, if there is a buildup of carbon which it doesn't take much.
what about Autolite 3095 plugs,anyone use these?
I used to run the 3095s. Until I tried a set of Xs I never knew the difference. Once I put the Xs in there was no going back.
.018 to .022 gap would be correct for running an after-market Bosch DU4 magneto without an impulse for starting. Otherwise I usually run the gap at about .028 to .032 inch.
Drive carefully, and enjoy, W2
I got interrupted again. I always seem to get interrupted. I forgot to mention that I use a pair of needle-nose pliers to make adjustments on the early style plugs. I find them easier to control and less likely to break something.
Dc,ae,W2
The appearance of a Champion X is worth half the price of one. I run them in my truck. The Touring has some later one piece 25's that were in it when we got it and run fine, but don't look as good. I have a set of X's I got at a swap meet. I should put them in when I think about it. I also have a full set of brand new X's that were on the shelf at an auto parts store. Not sure of the vintage. I'm guessing 70's or 80's. I just haven't wanted to take them out of the box and you can usually find used ones at swap meets.