Haven't checked the plugs in three years, car was running with a miss after a run and starting up again after 30 minutes.
The Edison #14 plugs all showed white-grey with no deposits. Front two had .026-.028 gaps, the back two had .037-..040 gaps. I could attribute electrode wear and heat from use, but why the difference in gaps from use ? Normally the #1 plug usually will foul due to cooler operating with " Thermobarf " cooling ( RD Rick's coined that word ).
Checked sediment bulb, gas line, carb bowl,.... all free from gas tank debris.
Installed a fresh set of Edison 14's, went for a 30 mile ride this morning..... smoother engine, noticeable pep, .... guess that means better ignition timing at the plugs, all with .025" gap now.
Waited 30 minutes after shutdown to re-start & go for ride, no "one cylinder" chugging as observed before the plug change, smooth as the first ride this morn.,
I concluded the very long center electrode in the Edison 14's will move under high engine temps when car is parked. , observed the center electrode not centered in the plug , but moved away from the ground electrode.
.025 spark plug gap is recommended for good magneto ignition.
Would appreciate responses from Edison spark plug users , similar experiences ?
Thanks in advance...
Thanks for the testimonial!
I have only had my new Edison 14s in my '24 for a month now, so far so good. My car came to me missing its magneto and running a Truefire ignition.
So far, the car is peppier with the Edisons than it was with the Champion Xs, but that may be because the Edisons are gapped at 0.030, whereas the Champions were gapped at 0.025.
My observation on the different larger gaps points to a ignition timing change in those cylinders..... cylinders 3 & especially #4. ..... creating the problem.
".025 spark plug gap is recommended for good magneto ignition." by who or are you talking about outside magneto like Bosch or such and maybe a high compression head.
For stock head, magneto and coils, the gap is recommended as a thin dime which is about .030 to .032 in anything I have read.
Maybe your engine is telling you it needs a wider gap!
It takes less to jump a narrow gap under compression then a wider gap. A good Ford magneto should be able to provide power for the wider gap.
The NOS Edison #14 plugs were factory gapped at .025". ...... all 4 of them. Their listing for that plug is specifically for the Ford car.
from another current thread .....
By Dan Treace, North FL on Monday, June 15, 2015 - 10:47 am:
Recheck the gap on the plugs.
The higher compression requires a fat spark, a short one is better, so gap needs to be tighter.
'Z' head on my '27 with Stipe 280, Anderson timer, coils and hot magneto, and Champion 'X' plugs required the normal .025" gap, worked fine. Any larger gap and noticed power drop off.
I like the look of the Edison #14 plugs on the Model T. Not only do they function just as good as the Champions, they are a historic connection to the friendship and mutual respect between Henry Ford and Thomas Edison, who was one of the few men Ford idolized and respected, as he worked for Edison as a young man. Jim Patrick
You should get somebody to check your coils...LOL. Seriously though, the color is good so what's the difference between 1-2 & 3-4? Aside from 2 possibly poorly manufactured plugs wearing more. (not likely but possible). Could they be running hotter or slightly leaner?
Jim, you summed it up perfectly, that's why I installed a set of Edison 14's on my 1924 cut-off touring (now a pickup)!
I love it when someone is looking over the car at a car show and notices the plugs, it's a great conversation starter.
Hey Charlie..... The center electrodes on the #14's extend out from the ceramic insulator about 1/2". .... the possibilities of movement from center from pressure, heat and spark explosions are plausible.
Inherent defect in manufacture ? I would classify this design as a very hot running plug.
The cooler part of a running engine is in the front due to thermosyphon circulation and forced air from the fan & forward movement in travel. Hottest would be at #4 cylinder... less air movement, hotter coolant plus the combined cylinder exhaust manifold heat transfer to the block.
No need to check the coils, the E-Timer insures intense spark as shown on removed plugs.
Engine runs great with .025" gapped plugs, problems with .040" gapped plugs.
Hey Jim..... Appreciate the Edison/Ford freindship connection also. Thanks for mentioning.
Is Ward's #1 the same as Edison #14 and Champion X?
Steve: Have any specs or picture of the Wards #1 ? Have noticed different length center electrodes on various Champion X plugs, The Edison #14 has 1/2" exposed.
Observed gaps after 3 years useage were greater in cylinders 3 & 4 I determined from engine heat , and possibly from my lack of yearly/seasonal checking/maintenance.
Here's the Ward's plug. Looks a lot like Champion X to me.
Center electrode same length ? Shell looks like a 1/2" pipe thread.