So it won't charge & you're going to convert it to 12v? Why not check out the generator, battery & v/r before you just start replacing parts?
From my experience, I've only found two reasons to convert an N to 12v: If you need to run 12v equipment (sprayers, pumps, lights, etc) or your N has poor compression (like less than 90 lbs) and you do not want to rebuild it, then a 12v conversion makes sense.
Otherwise, some folks end up trading one set of problems for another. If an N is hard to start in cold weather (or any weather) they should find out why & fix it! These tractors have low compression, low HP engines and will start just fine on 6v.
There is nothing inherently 'wrong' w/ a 12v conversion. The problem is that there are about 6 different ways to convert the tractor to 12v, all of them work, and an infinite number of ways to do it wrong. If the owner has a basic understanding of tractor mechanics, he could buy a quality kit & do it correctly. Or, he could buy an alternator & fabricate brackets. Of course, if the owner had a basic understanding of tractor mechanics, he could just as easily fix the problem that he was trying to cure with the 12v conversion. Most problems we read about w/ 12v conversions are as a result of folks getting in over their heads trying to fabricate a conversion, using inferior kits or using kits w/ directions written in Chinese, or buying tractors w/ "Bubba" conversions and now the new owner is stuck with trying to figure it out. I can tell you that a wage earning mechanic known to many of us on this board summed up every conversion kit he was familiar with by saying that all are bad & some are worse. He makes his own for that very reason.
All four of my N's are 6v & they all four start the first time, every time, no matter what the weather. You will find that to be the case with folks who live in a lot of places much colder than VA.
Now before the 12v advocates give me a spanking, let me add that lots of folks around here have 12v conversions & are perfectly happy w/ them because the conversions were done correctly. 12v is also more forgiving of poor grounds/weak cables, etc than 6v, so keeping everything "clean, bright & tight" in the system is not as critical. 12v gives you twice as much current & a faster spinning starter. And, because 6v headlights are 35w & 12v are 55w, the headlights are brighter.
You will spend probably $160 for a kit. If you install it correctly you will have an easy starting tractor for a long time. And, the 12 conversion will have just about nothing to do w/ the good performance. What will make the real difference is the new wiring, cables, clean grounds & new battery.
Plenty of 6v tractors start just fine in MI, NY, WI.....and have been doing so for years. Because they have the correct size cables, good batteries, & clean, bright & tight grounds & connections. And, the correct gaskets in the distributor.
This post is a good example of what I'm talking about:
"kilroy
07-25-2009 19:19:52
72.13.217.35
724129 <http://www.ytmag.com/cgi-bin/viewit.cgi?bd=nboard&th=724129>
my 48 8n is 6v with points in a front mount, and at -30 it fires right up, no block heater, just have to tend the choke for a minute. Have run in the rain and snow and have never had to dry the disributer, just used all the little gaskets and guess it sealed up. I like the points because if they do get wet, dry them, they work again, dont know if the electronics are that way but they cost a lot more to replace than points I'm sure"
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