Losing spark

[EdGooding]

No, not that I've seen. Isn't that for a 12V system? Unless its in the cutout box itself.

Yes, you would only need the extra resistor if you converted to 12v and kept your 6v coil installed. It would not be in your cutout, only the wire to your coil. Your cutout is irrelevant here. It is part of your charging circuit and your problem is in your ignition circuit. If your battery is being charged with the engine running, then you can discount the cutout and generator as part of your issue.

Do you know how old the ballast resistor is on your 8N? Perhaps that is malfunctioning and messing the voltage up enough to impact your coil? You could take a voltage reading on it with your engine fully warmed up but running right, and then do it again when the engine starts running badly. Should answer the question about your ballast resistor being bad. If you need a new resistor, it is $8 from Just 8Ns: 9N12250-9N12250 Years:1939-50 Resistor Only (No Mounting Blo or you can get the full unit with the mounting block for $22.

 

[jimjumper]

How can I tell for sure that the generator is charging? And is it possible that the battery itself has a bad cell? I'm starting to run out of parts to replace! I have a new resistor. I'll put it in and try.

 

[SPYDERLK]

How can I tell for sure that the generator is charging? And is it possible that the battery itself has a bad cell? I'm starting to run out of parts to replace! I have a new resistor. I'll put it in and try.

Have you replaced the condenser?

 

[jimjumper]

Yes. The tractor had been sitting when I got it. Replaced condenser, coil, points, ignition switch, battery. That got it to turn over. Replaced gas tank, fuel line, and screens. that got gas to the carburetor. Replaced the carb and spark plugs. Charged battery, got it to start and run. After about 2 hours running started popping and missing. I am still at the no spark step of getting it to run right. I've also replaced the flat tire and the leaking radiator, plus the generator, cutout, starter relay and starter pinion gear.. Like I mentioned, not many external parts left.

 

[EdGooding]

How can I tell for sure that the generator is charging? And is it possible that the battery itself has a bad cell? I'm starting to run out of parts to replace! I have a new resistor. I'll put it in and try.

Attach your voltmeter to your battery terminals. With the engine off, it should show around 6.2 volts. With the engine running, it should show a reading of around 7.2 or a little more.

If your battery has a bad cell, it is likely that your 8N would not even start. But, you can load test it to verify it is working. You can take your battery to about any auto parts store and they will load test it for you. If you want to be able to check that yourself, you can pick up a 6/12v load tester from Harbor Freight for about $20.

https://www.harborfreight.com/100-amp-612v-battery-load-tester-61747.html?utm_source=bing&utm_medium=cpc&utm_campaign=425671834&campaignid=425671834&utm_content=1159985793876517&adsetid=1159985793876517&product=61747&store=741&msclkid=86651d4f4a291e041d537be969680c3b

 

[jimjumper]

Yep, already have one of those and it indicates the battery is good. I don't show that much when its running, about 6.5-7 volts but that should certainly be enough to power the coil. I'll replace the resistor block this morning and see what happens. i'm kinda clutching at straws here now.

 

[SPYDERLK]

Yes. The tractor had been sitting when I got it. Replaced condenser, coil, points, ignition switch, battery. That got it to turn over. Replaced gas tank, fuel line, and screens. that got gas to the carburetor. Replaced the carb and spark plugs. Charged battery, got it to start and run. After about 2 hours running started popping and missing. I am still at the no spark step of getting it to run right. I've also replaced the flat tire and the leaking radiator, plus the generator, cutout, starter relay and starter pinion gear.. Like I mentioned, not many external parts left.

In that case I think it is the distributor cap.

 

[jimjumper]

Cheap enough, I'll get one tomorrow. Thanks, Jim

 

[SPYDERLK]

Cheap enough, I'll get one tomorrow. Thanks, Jim

Old ones get fine internal cracks, absorb moisture. May be ok cold but warmth brings out the moisture, and sparks from the rotor start following the cracks every which way. The hint is the spitting and popping. Id get a new rotor too if you didnt already.

 

[jimjumper]

Minor problem with getting anything done today...Over 300 acres already and its only 5 miles away. Sorry if this is off-topic.