weird spark problem!!

set gap to match coil

http://www.ytmag.com/articles/artint268.htm

Infact, Champion used to sell a special internal gapped sparkie for just this problem.

Me? I'd just replace yer sparkies with "hotter" AutoLite AL437's gapped 0.025".

Then I'd check the ignition coil polarity. Incorrect polarity can LOOSE upto -40% of yer sparkies.

Since I don't know the gory details of yer 12-volt conversion, the tractor could have the old original 6-volt coil that has molded "points" on one of its terminals, or it could have (+) molded on one of its terminals. In either case, (+) to the distributor points feed-thru is WRONG 'cuz yer 12-volt conversion points are negative ground.

Recommend a real 12-volt ignition coil with NO RESISTORS. The NAPA IC-14SB ($15, cheap) is popular and even has hotter sparkies too. Coil (-) to the distributor points feedthru. Simple, eh?..... ..Dell, yer self-appointed sparkie-meister

That was the term used for all sorts of "doohickeys" back in the "old days" that accomplished what you are doing by holding the wire away from the spark plug.

Read all about them at the link below; including how they make a "carboned" plug fire:

• Spark it...

In fact, you can make a dandy transmitter out of almost any car, from any year, using the battery and one of the relays. You can make a better one using the coils in a car so equipped; many old Ford coils found their way into transmitters in the Model T era.

Back to Meisenner: They produced a VERY popular transmitter, with an 807 final IIRC, as late as the "forties and "fiftties:

Link

So, thanks again, Bob, for bringing this to my attention.