12volt system

I have an 8n with a 12 volt conversion. Tractor was running great and then just stopped on my 2nd day of brush hogging. Not getting any spark, I rebuilt the distributor with new points, condenser, rotor and distributor cap. Still no spark, any suggestions? Coil perhaps, saw earlier post on how to check coil. Any help would be appreciated.

(quoted from post at 14:41:15 04/06/15) I have an 8n with a 12 volt conversion. Tractor was running great and then just stopped on my 2nd day of brush hogging. Not getting any spark, I rebuilt the distributor with new points, condenser, rotor and distributor cap. Still no spark, any suggestions? Coil perhaps, saw earlier post on how to check coil. Any help would be appreciated.

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Coil perhaps, saw earlier post on how to check coil." Easy enough. Get 'er done.

Polyranch........I flunked mind reading, just ask my ex-wife of 32-yrs. Since you didn't specify whether you have the early front-mount 8N or the later side-mount 8N, I'm gonna make some general observations. As a general rule, even the weird 4-nipple front-mount coil is semi-bulletproof, BIGGEST problem is replacing the points. (0.015") You need to "polish" the INVISIBLE corrosion from between the points (0.015") Me? I clamp the corner of a $1-bill between the points (0.015") and pull. Iff'n yer really cheap, tear a strip from heavy brown paper grocery sack and use that. Simple, eh? Same rule applies fer the ROUND side-mount coil, polish the points (0.025") with $1-bill. (NOTE the difference between points specifications) Final observation, points and condenser work well on either 6-volts or 12-volts. (they're good fer about 200-volts) Same with rotor and dizzy cap. ONLY the coil is voltage sensitive which is addressed by resistors. ......HTH, Dell, yer self-appointed sparkie-meister

" Not getting any spark, I rebuilt the distributor with new points, condenser, rotor and distributor cap. Still no spark, any suggestions?"

Yes.

Troubleshoot the problem before you start buying parts.

Before I offer you some help w/ your problem, bear with me for a minute as I share a “learning moment” for others facing a similar issue.

What you have done is replace good working parts in an attempt to fix an undiagnosed problem. I’ve done that and I’m sure others around here have done it too.

You have spent probably $50 plus hours of time & frustration w/o having the slightest clue as to what is causing the tractor to shut off & not restart. Worse yet, by replacing all of those parts, you have probably introduced more problems.

The one way that I found the best results with is to take a systematic, step-by-step approach to solving the problem, working from most likely to least likely. The trick to fixing these tractors (or trouble shooting any piece of equipment) is to be systematic about it. You need to isolate the problem step by step and work from most likely to least likely. Jumping ahead to 'so-and-so said it could be whatever' or just replacing parts usually just wastes your time and your money. I know it did for me.

You have solved half the problem by determining it is a spark problem. That doesn’t mean you need to replace all of the electrical parts on the tractor! 

Get your meter out. The ignition circuit goes from the battery to the terminal block then to the switch then to the coil. Trace the circuit. Post back w/ results.

(HINT: ignition switches fail & wires come loose a lot more often than a coil goes bad)


I might not be capable of telling you why your tractor isn’t running, but I sure can tell you how to figure it out for yourself.

And if you want more specific advice on finding your problem, tell us if it's a front or side distributor.
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All, thanks for your feedback, it is a front mount system, coil was good, turned out the original points were bad but when I pulled the coil I had bent the spring forward and didn't notice it, I straightened it out and reinstalled it and it started right up and runs smooth. I had a spare distributor housing so I pre built it and had set the point gap at .015. Thanks again for the feedback.