JD A spark plug type

[Frank Vantacich]

I have an unstyled A serial # 457910 and was wondering what part number spark plug seems to work the best for you guys.

 

[BMAN]

Autolite 3076

 

[John T]

If its old style 7/8 plug, I recommend the hotter deep reach side wire electrode Autolite 3077. For the later models with the 18 mm plugs the non resistor Autolite 3116 especialy for a Magneto Ignition.

John T

 

[Carlyle hoffman]

3077,s are HISTORY, no longer AVAIL.If it RAN on them before, it will RUN again on 3076,s.

 

[John T]

I still see plenty of them at tractor shows, better stock up it sounds like. I always had less fouling and less carbon/soot build up on them (hotter, deeper reach, side wire electrode) then the conventional style 3076 plug. Of course, if we still used the tractors hours a day under full load and at operating temps like they were designed versus light duty parades, the standard heat range (3076) would do fine grrrrrrrrrrr. I run my carb lean as possible and shutters etc to get the temp up to 180+ which reduces premature plug fouling and carbon build up.

John T

 

[Randy G]

I run AC C88L in my 2-49 B"s, 50, 520, and 530. Never a problem!

 

[John T]

Yep, those are good plugs, and the later model tractors especially with two barrel carbs, better ignitions, and the later 18 mm plugs dont foul near as bad, however since he has an Unstyled, Im guessing he may have the older 7/8 plugs in which case those don't fit absent special adapters, so hes stuck with 3076 or my preferred 3077........

John T