No spark at points

Hello guys, I'm new here and need some advice. My 58 cub ran like a top, never once failed to start, then of course before a big snowstorm it wouldn't start. I began diagnosing the problem and found the external resistor on the coil was bad, so I decided to replace everything starting with a coil with and internal resistor, distributor cap, rotor cap, condenser, points and plug wires, put it all together, set my points at .020....nothing, popped the cap off and I have power to the points but no spark at the points, I am stumped. Any ideas ?

I should mention when I first found the external resistor was bad I simply connected those wires, bypassing the resistor, it started immediately and ran for about 2 minutes then abruptly shut off, just like you shut off the switch, haven't been able to get as much as a chug out of it since. Any and all help would be appreciated. Thank you

Well the new coil doesn't have a resistor in it. it is just wound with more turns of finer wire so it matches 14+ volts of charging running tractor.
The bypassing of the resistor may have caused associated problems. Using a 12v test light (plastic handled probe with a wire to ground) first
determine if there is voltage at the coil from the ignition switch. Switch on bright light, go to opposite side of coil. No light means the points
are closed (good because engines usually stop with the points closed) or the wires in the distributor are touching ground. If the light is on almost
bright, the points are open, or closed but have a production film on them that prevents conduction. or the wire going to the distributor is bad/broken
internally.
Remove the distributor cap. With the ignition off, turn the fan until the points are closed if they aren't already. turn on the ignition and touch
the movable point with the probe. If it lights, the points are not actually conducting electricity. Shut off the ignition, and use alcohol, or
fingernail polish remover on a Q-tip to clean them, then a folded dollar bill to final wipe them to be sure there are no fibers in there. If there was
no light when you tried it (prior sentence) the through terminal passage where the points and condenser attach inside and the wire attaches outside
may be shorted, or open at the metal of the housing. With the points open, and ignition on, there should be lights on at the movable point. Using
the tip of the probe to bridge the points should produce a small spark. There are bad condensers that are new. There are bad coils new. the point
gap is .020" with the points rubbing block on the high point of the 4 lobed cam. Jim

First thing I would do is put the old condenser back in. Now days you stand a 50/50 chance the new condenser is bad. I have not replaced a condenser in over 2 decades.

Try this. With the cap and rotor off turn the engine till the points are open. Slip the tip of a screwdriver between the points with the ignition on. When you do that you should get a small spark. No spark means you have a short or not getting power to the points.

Next get the points closed and carefully open them by hand and you should see a small spark. No spark means points need to be cleaned or you have a short or no power to them

Thank you for your response. Ok, when I bypassed the broken resistor it was with the old points and condenser...etc, like I said the tractor started immediately and ran for about two minutes. My " no spark problem came into being after I replaced everything. With key on using my test light I have power to + side of coil, when cranking the engine I have power to the primary terminal, with cap and rotor off and cranking I placed my test light on to band coming from the primary post and have power there when cranking, but I see no spark at points,. Two questions...1: should I test for power as you said with points closed and key on. 2: is a external resistor still needed or even a good idea with my new coil ? Could it be a bad condenser ?

With the ignition turned on and the points closed you should not have the test light lite. With the points open the test light should light. If you spin the engine over the test light should blink on and off. That is with it hooked to either side of the coil. If it lights with the points close the points need o be cleaned I my self use the flap from the box the point come in to clean the points. Fold the flap in half rough side out and then slip them between the points

And yes it could also be a bad condenser put the old on back in

By my understanding the way old stated this is a little confusing when he speaks about the test light ..hooked to either side of the coil.. To me in general use of a test light the wire lead with the clip on the end is connected to a good grounding point and the pointed probe is held to various locations looking for battery power at that point. I believe in his explanation that of that instance he is suggesting to connect the light across the coil terminals to cause it to blink. My method of testing point operation is to use the test light in the normal way by grounding the wire lead clip and checking for an on..off blink on the coil terminal from the distributor while cranking the engine with the ignition power on.If the coil you purchased is for use with full 12 volts as I am assuming your tractor is converted to run on 12v then you DO NOT need an external resistor. Most coils like this have ..No External resistor required..printed on them. The positive terminal of the coil should maintain near battery voltage at all times.

It is a given to hook the clip to a good ground so I do not say anything about that and I figure a person know that if they know how to use the light in the first place

(quoted from post at 09:26:59 01/12/21) Hello guys, I'm new here and need some advice. My 58 cub ran like a top, never once failed to start, then of course before a big snowstorm it wouldn't start. I began diagnosing the problem and found the external resistor on the coil was bad, so I decided to replace everything starting with a coil with and internal resistor, distributor cap, rotor cap, condenser, points and plug wires, put it all together, set my points at .020....nothing, popped the cap off and I have power to the points but no spark at the points, I am stumped. Any ideas ?

I should mention when I first found the external resistor was bad I simply connected those wires, bypassing the resistor, it started immediately and ran for about 2 minutes then abruptly shut off, just like you shut off the switch, haven't been able to get as much as a chug out of it since. Any and all help would be appreciated. Thank you

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Long shot but check for spark at spark plugs also. If you are visually looking for spark at points it can be hard to see. I read your post in a hurry so if youve covered this I apologize .

(quoted from post at 12:03:28 01/12/21) It is a given to hook the clip to a good ground so I do not say anything about that and I figure a person know that if they know how to use the light in the first place

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Yeah that's a given, I am a pretty competent mechanic, I do all my own car work, lots of time on heavy equip, haven't messed with anything with points since my 68 chevelle, anyhow the problem was a wire going from the negative side of the coil to the alternator, since I had tried everything else, consulted a man with a name " tractor guru" no less...lol I tried to reason why there would be a wire going to the alternator, I unhooked it and I had blue spark everywhere, it fired right up, but now it is not charging with that wire off so I will have to run it to the acessorie side of my switch I think. I touched it to the + side of my coil and it began charging, so my Cub is once again humming like a singer sewing machine. Thank you for the help, it is greatly appreciated.

The real problem I think is the man I purchased the tractor from, from what I have found this far always took the cheap easy way out when fixing something on this tractor, before this problem I had a problem with my battery going dead, even with the switch off which I found he had it wired and it was backfeeding through the alternator, I corrected that when I replaced my clutch, which was another new cub experience, I think when summer gets here I am going to do a complete rewiring because there are numerous wires just dangling and I can't have that, the summer before last I flipped it over backwards and just got clear before the steering wheel and seat were completely crush, it did get my leg, which tookseven operations to fix, 6 months off work and a helluva lot of pain, we're old friends now...lol. Thanks again for your help

I often times to save wire run the excite wire to the ignition side of the coil with a diode in line so the alternator doesn't back feed the ignition when you shut the switch off. The negative side of the coil should be hooked to the distributor as in the wire running to the points

(quoted from post at 13:16:12 01/12/21) I often times to save wire run the excite wire to the ignition side of the coil with a diode in line so the alternator doesn't back feed the ignition when you shut the switch off. The negative side of the coil should be hooked to the distributor as in the wire running to the points

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Ahhh, I love this. Ok so where do I get one of these diodes, and what size ? This won't hurt anything running it to the hot side of the coil ? As I said I touched it on the hot side and it did excite my alternator and began charging right away, but I wasn't sure if I could safely hook it up there.

Electricly speaking it doesn't matter if it is hook to the switch which by the way takes more wire or to the ignition side of the coil. As for a diode if Radio shack was still around I could tell you where to find one but there not. Doesn't take a big diode say one that will handle 1 or 2 amps. Or you can used an O'Reilly's' part # VR-1 ballast resister and it will do the same job as the diode

Thank you sir, enjoy your evening

Always happy to help if and when I can

Glad he got it going, the old missing info about the added alternator wire problem. To ..old.. my point was NOT that you did not explain the proper use of a test light but rather by reading the way you wrote it could have easily been understood that the terminal on the coil powered by the ignition switch should blink when the engine is cranked. On a 12 volt system with a coil that does not have a resistor it should not, it should be on 100 percent of the time the switch is on. On a system with a coil that has a resistor feeding the coil, the voltage at the powered coil terminal will alternate bright to dim repeatedly, but I would not call that blinking. I know you know what you are doing it is just that the words you used could have been misunderstood by the OP, on to bigger and better things! Thanks for taking the time to help him out.