Coil wire

TOMS

Junior Member
Today I discovered that the high voltage wire between the coil and distributer has 7,000 ohms resistance and is about 14 inches long. Appparently it is for a more modern car with a radio. Is it OK to keep this wire or should it be replaced with a new one from the Model A suppliers. Thanks.
 
Always useful to have a length of the old style coil to distributor high tension lead ready in your garage as it's not usually kept in stock by motor factors these days.
Having said that if your A runs Ok and neither the coil nor condenser gets hot I guess youe can presume the modern type is working adequately.
 
I put a new coil wire on mine at the same time I put a new coil on. I had
problems, but not sure if it was the coil or the wire, so put the old wire on
and it was good to go. Later, I determined that the old coil was good as well.
It turned out that the screw was loose causing it to leak.

Jack
 
If you have a radio in your Model A the resistance wire will cut down on some of the noise, but the original wire was stranded Copper and the ends were soldered on. The resistance wire will reduce the spark slightly since it obeys Ohms law(V=I X R) so if the resistance is 7000 ohms you will get some voltage drop due to small amount of current flowing through the wire. Old Rule of thumb was 1 K volts per thousands of an inch gap. Spark plug voltage is very high and very little current. Will still let you know if you happen to hit one of the spark plug wires while the car is running. If it runs fine with the resistance wire why change?
 
For years carbon wires were a source of hard starting on my motorcycle, until one day when I got caught in the rain and the motorcyle died and wouldn't restart. I found someone had installed carbon wires and the carbon had burned away for about 1/2" in the ends. I installed the correct solid wires and the motorcycle now starts on the first kick each time.

Yes, you DO want solid wires on your Model A.
 
In my experience working on 6 volt flathead industrial engines, the solid core wire worked better for plug wires and coil wires. Of course we weren't running any radios. You can buy a roll of wire and the ends at a parts store and assemble the ends and boots yourself. You can get either 90 degree ends or straight ends and boots for the plugs or distributor. I always kind of liked making up my own wires, but you need a good set of crimping pliers made for plug wires to crimp the ends on properly.
 
Similar input from my experience with 6v positive ground tractor engines: ditch the resistance wire - they run better with the older style.
 
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