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Ford NAA - No spark

My NAA was running perfect until I left it parked in my pasture and my cows decided to rip the wires off the distributor and the one wire from the distributor to the coil. I replaced the plug wires, which was easy enough. I replaced the coil wire with a standard (12 gauge - I believe) stranded copper wire.

I am not getting any spark to the plugs now. I did the old ground the plug to the block test and I have a tester (the one that you hook up to the wire and ground with gator clip). No spark. I am guessing there is a possibility that I did not have a good ground (they paint everything LOL)

I have done a primary coil test with my craftsman ohm meter; it registered about 1.9 and the secondary test came in around 9.0. If I turn on the key and test the voltage on the input side of the coil, it reads 5.4 volts; not sure if this is a legitimate test or not.

Guessin you all realize the difficulty is that it ran just fine prior to the cow eating fest. I have stared at the thing repeatedly and not sure where to go now.
I did notice the original coil to distributor wire was braided, but it was silver in color and not the orange color that copper has. Is it possible that the copper is impeding the spark? Is there some type of low resistance wire that is required between the coil and the distributor?

Re: Ford NAA - No spark

pic follow up

Bob in KS Use any common wire from output of coil to side of distributor. Yours looks ok

5.4 volts at input to coil is low. I assume this is 6 volt system. Be sure battery if fully charged.

Coil input should be near battery voltage. Output of the coil should be same as input with points open and near 0 volts with points closed.

What about wire from input of coil back through the switch. Other wires could be pulled loose.

With the points open I'm getting only .4 volts coming out of the other side of the coil. Tried a different coil with the same results. Definitely not getting spark. I'll check the wire from the switch since you said 5.4 seems low. I did make sure the battery has/had a full charge. Need to fix a fence; using backhoe instead of tractor w/ auger since it isn't running. I'm going to look into the wire coming from the switch, it sounds suspect. Perhaps the low voltage is the whole issue.

Jim L Hi Mike, welcome to our little used forum. Like Bob said, with the points open you should be getting close to the 5.4 volts on that primary wire going to the distributor. Take a good look inside the distributor. It sounds like when the cow yanked on that wire it bent something in there to cause the terminal to ground out. If you lift the new primary wire off the distributor and using your ohm meter, I'll bet you see that terminal grounded and I would also suspect that you will then have closer to 6 volts at the coil. Let us know.
Mike Will do, still fixing fencing, but something you said corresponds to what my neighbor said he saw. My neighbor is manager of roads, vehicles, maintenance, etc. of a large township; so he's a wealth of knowledge when it comes to anything mechanical. He had me turn the key on with the points open and he said that he saw a spark inside the dizzy; however, we could not repeat it. Now I'm thinking that he maybe really did see a spark. The wiring inside the dizzy looks solid, but of course that doesn't always mean it is.

Going to test your theory in a little bit. Catching some air-conditioning....been working in this sun all weekend.

Thanks for the replies, this one is tricky.

BobV KS Also check for broken feed through insulator on side of distributor. yanking on wire could have broken that and caused feed through screw to short to distributor case
Mike I was able to get back to this tonight. Asraticallf suggested I disconnected the wire from the coil to the distributor. I was then getting current to both sides of the coil. I I took the cap off and disconnected everything. Put the wire back on from the coil to the distributor. I still had current. So I started reassembling all the wiring inside the distributor constantly checking If I had current. Well, its all back together and I have current; so theoretically it should start now. I have to charge the battery first and I'll report back tomorrow. I'm betting that its going to start.

Also, as suggested, I checked the insulator and it was not cracked although that assembly was a bit lose until I reassembled everything.

Talk to you all tomorrow.

OK, so the tractor started this morning; almost immediately. Looks like there truly was short inside the distributor due to the cow ripping off the wire from the coil to the distributor.

So I'm good to go and thank everyone here.

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