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Discussion Starter #1
I was helping my neighbor today with his Farmall 350. This tractor has been kept inside his tractor shed but hasn't been ran for a while. We installed the carb I rebuilt for him and tried to start it. Wouldn't start. I asked him if he checked to see if the tractor had spark and he said he didn't check it. So here's what we did. First I put an inline spark tester between the plug wire and the spark plug. Cranked it over, - no spark. Next we swapped out a coil from a Super M. Still no spark. Next we put the original coil back on the 350 and got a test light out and turned the key to the on position. When I put the probe on the (+) side of the coil the light lit. I put the probe on the (-) side of the coil and the light lit. I did the same test on a Super M and a Super H he had there. On both of these tractors the light only lit with the probe on the (+) side of the coil, which is what I think it should be. The cap and rotor don't look bad. Is there any other test I should do? If not, what do you think the problem could be?
 

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On our old tractors that sit for a while I usually find the points get corroded and need to be cleaned up with a point file. Its been a while since I checked a coil so I'm not sure on it.
 

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Guessing the points on the 350 is making contact, and the other 2 are not. Pull the coil wire on the Super M, or H, put your test light on the - side, and roll the engine over with the starter. Pretty sure the test light, will light, flashing when points make contact.

If that is the case, then try it on the 350, and see what happens. If it does flash, while turning over, pull the cap, and look inside checking for a buildup on the lugs. This is caused by ionization. If there is a build up, you can scrape that buildup off with your pocket knife. just go easy, and clean it up bright. Aluminum lugs seems to be worse at this, than the brass lugs. Brass lugs with have a greenish-gray carbon like buildup. Aluminum will be dark gray, to black.

I usually had to do this to my one Super C, once or twice a year. Seemed to be worse when we had a damp Spring, where you may get some condensation in under the cap, or go through more than several Spring sweats, going from 20º weather, warming quickly into the 50's, when you have high humidity.

Check the points to make sure they aren't burned. You can pull them, clean,and re-gap. If they are burned bad, time to replace with a decent set.
 

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When I put the probe on the (+) side of the coil the light lit. I put the probe on the (-) side of the coil and the light lit. I did the same test on a Super M and a Super H he had there. On both of these tractors the light only lit with the probe on the (+) side of the coil, which is what I think it should be. The cap and rotor don't look bad. Is there any other test I should do?
Yes. Check for ground continuity on the (-) side of the coil with an ohmmeter. It sounds like that wire is open; look for dirty or bad ground connection, chafing, broken wire, or maybe even rodent chewing.
 

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Thanks guys for the replies. I'll know what to do and what to look for when my neighbor and I get back to the 350. He is having some health issues and might require surgery. I will reply back when we get it running and what the problem was. Thanks again for all your help.
 

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Discussion Starter #6
Just wanted to give an update. I'm not one of these guys that asks for help and never follows up with a reply. I hate when people do that because you never find out what the fix was. Anyway, I saw my neighbor over the weekend and he is going to get his back operated on in March. He can't stand very long and has to use a cane when he walks. He's had 3 back operations so far in his life and will celebrate his 80th birthday this Saturday. That's the situation as it stands now. We won't be working on the tractor until he's recovered.
 

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Sorry to hear of his upcoming surgery, hope they have success, and can help him out. At least maybe the weather will be nicer by then to work on it, and give him some incentive to get back at it.
 
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