12V front mount coil question

I switched my front mount 8N to 12V several years ago and at the time for monetary reasons, I used a 12V to 6V resistor and the stock ballast resistor w/6V coil rather than buying a 12V square coil. I would like to "finish" the conversion by putting a 12V coil on and removing the resistors. Will the square 12V coils stand up to the alternator current? I've read they aren't up to it without some resistance inline. I would really like to use a round auto type coil and be done with those square ones, but the "gut the old one" seams to be the only method going and from what I read there are a lot of the newer one that aren't "gutable"? Any other methods for this out there? any advice/info welcome.

If you go out and buy a so-called "12-Volt" square-can coil you need to use the OEM ballast resistor with it.

There's more than one way to use a "round-can" coil.

...Home-made gutted-out coil

...Pertonix makes a gadget to sit in place of the coil and facilitate the connection of a "round-can" coil.

...In the past, I've modified a few distributor caps to include a high-tension tower. I keep promising to whip one up and post a photo, but never seem to "get'r done"!

My experience is to use a resistor, even with the square, front mount 12V coil. I learned the hard way. After burning up a couple, this forum straitened me out. Good Luck

What resistor are you using with your 12V front mount? Thanks

(quoted from post at 01:26:58 03/04/09) I switched my front mount 8N to 12V several years ago and at the time for monetary reasons, I used a 12V to 6V resistor and the stock ballast resistor w/6V coil rather than buying a 12V square coil. I would like to "finish" the conversion by putting a 12V coil on and removing the resistors. Will the square 12V coils stand up to the alternator current? I've read they aren't up to it without some resistance inline. I would really like to use a round auto type coil and be done with those square ones, but the "gut the old one" seams to be the only method going and from what I read there are a lot of the newer one that aren't "gutable"? Any other methods for this out there? any advice/info welcome.

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When you get your 12V coil follow Bruce (VA) instructions on how to properly figger out the resistors needed

http://ytforums.ytmag.com/viewtopic.php?t=425321&highlight=

you will need the original resistor plus another one to b safe with the original type coil

(quoted from post at 20:26:58 03/03/09) I switched my front mount 8N to 12V several years ago and at the time for monetary reasons, I used a 12V to 6V resistor and the stock ballast resistor w/6V coil rather than buying a 12V square coil. I would like to "finish" the conversion by putting a 12V coil on and removing the resistors. Will the square 12V coils stand up to the alternator current? I've read they aren't up to it without some resistance inline. I would really like to use a round auto type coil and be done with those square ones, but the "gut the old one" seams to be the only method going and from what I read there are a lot of the newer one that aren't "gutable"? Any other methods for this out there? any advice/info welcome.

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rayburns, attached are a few pictures of ways the round coil conversion has been attacked without hogging out the sq can coil. One (1st) looks like it might have kin-ship with what Bob described in his post here. The Pertronix 'block-off plate' is a bit pricey at $100 to me (might as well go ahead & use their complete EI conversion). Additionally, the plate leaves no place for the condenser, but the creative could find the condenser a home outside the distributor. They sell the plate as a "kit to convert #1247 EI system to a #1247XT system", XT meaning external coil.


Most pictures are self explanatory, but the simple dwg is where Hobo just drills holes thru potting material, windings, core or whatever the drill encounters, in order to attach wires to the springy thing contact & HV contact, as I understand him, anyway.

Digging the guts out of an old 6 volt front mount coil is not that hard of a job. It just takes some time an patients. The old tar filled ones are the easiest but the later compound filled ones can be dug out but with more effort. I have done both. Either one took me about 4 hours work over several days. I dig at it for a while and then let it soak is gas to melt the junk in side. Sooner or later the coil breaks loose and the rest is just clean up and soldering. Sounds like you tractor is running good so you are in no hurry. Get and old coil and pick at it.

The only thing I don't like about the conversion shown in the picture is that it appears that every time you replace the distributor cap you have to modify it.

For that reason I would prefer the gutted coil approach, which I've done and seems to work well.

thanks for all the replies guys. After reading them and what I could find in the archives, I think I'm gonna go with a auto style coil (the local NAPA's want $20 for an IC14SB).

The pertronix EI would be nice, but for the money I think I'll stick with the points.

I think I'll try the "gut the coil" route, but I'd kinda like to keep my still good 6V coil intact, does anyone have a dead square coil they don't want? I'd be willing to pay the shipping cost. if so email me at [email protected]

btw Bob, I'd like to see how you put the coil wire in the cap.

Now that you all have me thinking, I'd like to ask a question...

After I gutted my square coil, I attached the positive terminal of the new round can coil to the terminal on top of the gutted square coil, which in turn is connected to the coil spring on the bottom of the square coil (I thnk its the coiled spring if I remember right).

Do I have the polarity hooked up properly ??

(I'm running the original 6V positive ground setup)

Thanks !!

You DONE GOOD!

How does it start/run after the conversion?

(quoted from post at 07:30:02 03/05/09) You DONE GOOD!

How does it start/run after the conversion?

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Bob,

If you were replying to me, glad to know I've got it hooked up right.

My tractor ran pretty good before the conversion, so I didn't notice a night and day difference. I mainly did it for peace of mind knowing that the round can coil would never fail (and because I like to tinker).

However, I did notice that after running her hard and shutting down hot, she re-started much easier. I attribute that to the fact that my square can coil may have weakened in the heat, and since I've bypassed the ballast resistor I always have full spark.

I did compare the spark produced by each setup using an old plug gapped to 3/16". It looked obvious to me that the round can spark was more robust. It was a dark blue from end to end, the square can spark was a light blue, with orange at the ends.

Related question: I have performed the conversion with the resistor provided. I did however install it in series with the original firewall resistor. My spark was weak but it would start after cranking a while. I used it for about a month until the engine died (as if turning off the key). I had no spark so I looked to the bakelight resistor form the kit. The back side was all crumbly and chalky but the spring itself was intact. When I turned the key to power the kit resistor started smoking (overheating). I removed it from the system altogether and just ran with the original 6V resistor. Spark is beautiful and tractor starts within 2 seconds now. 1)Do I need to re -instal a new resistor and bypass the original or will the original protect the 12V coil from the kit ? The 2 in-series seemed to be too much. What is the resistance of the one in the kit so I can reproduce from my local parts store ? Again, tractor starts and runs great but am afraid the original resistor isn't enough protection. Thanks for any help.