6V to 12V....

I know this isn't hard - my age is catching up with me so I need a little help. My neighbor put a 12V battery in his 2N tractor-
and also had a "resistor" wired in the ignition wire going to his 6V coil; but couldnt get it to run right -or run at all. I went
over and we put a volt meter on the resistor and had 12V going in and 3V coming out; so I replaced it with a new one. The new one
read 12V going in and 12V coming out; so we said - "Hmmm". LOL...we got the idea of doing away with the resistor and went to
Orscheln and bought a 12V coil and replaced the 6V coil and it fired right up and runs. So - question- does the "points and
condenser" care about voltage? Are points ok with 6V and/or 12V? Or what should we do? Thanks.

The points and condenser won't care about the voltage.
They will care about the current if it is too high.
If you have the original ballast resistor mounted on the
back of the dash and a true 12V coil, that's all you need.
But you do need that original style wire wound resistor.

ok...so tell me why the resistor if the 12v coil is mounted on the distributor... the resistor is up by the battery ?

Aftermarket resistors, like the ceramic ones, are a fixed value.
The original style resistor has a variable resistance based on
the heat caused by the current flowing through it.

When cold, it's about .5 ohms, basically giving you full current
flow for starting. As it heats, it increases to about 1.7 ohms limiting
current through the points and coil to ~4 amps so they don't burn.

It heats rather quickly and gets red hot. It is screwed directly to the
bracket on the back of the dash. The dash helps dissipate the heat.

If the new one had "12V going in and 12V coming out," you may have been trying to measure voltage drop in an open circuit (points open). The voltage drop through a resistor cannot be measured with a voltmeter unless the current is flowing.

okay...so use a new porcelain resister infront of the 12V coil and should be fine....correct?

"okay...so use a new porcelain resister infront of the 12V coil and should be fine....correct?"

No. Use the original resistor and forget the porcelain.

(quoted from post at 20:33:58 02/13/18) ok...so tell me why the resistor if the 12v coil is mounted on the distributor... the resistor is up by the battery ?

Click to expand...

It's a "series circuit", and the physical mounting location of the resistor doesn't affect it's electrical function.

GUESSING Mother Ford put it there 'cause it's out of harm's way and protected from the elements.

It's a tried and proven design that's worked well for 76 years (in the case of a first-year 2N).

You are questioning it WHY???

When I look at the "conversion kit" on this site under 2N parts- it doesn't even list a resistor in the kit; like you dont need
one. However, I will get a new original resistor and wire it infront of the 12V coil. Thanks for your help.

I know nothing about 12 volt conversions. Mine is still 6 volt. Ford used a resistor to cut the 6 volt down to 4.8 volt thinking points would burn with higher voltage. Due to starting problems ran 8 volt batteries for at least 30 years to get more voltage to fire. Few years ago could not get 8 volt so went back to 6 volt battery. worked but not correct but tractor would stop and not restart for quite a while. Thinking it was ignation switch was changed several times but no change. I finally wired in 2 seperate switches and left orignal in. The new switches I wired direct, one to resistor other without. It would stat but not easy going thru the new switch and the resistor same as orignal switch. Using the direct it started better. So I tried an expermint, when it would start to die with either one going thru resistot turn switch without resistor and it would take off and run good, go back to resistor and it would start to cut out and die, go back to the bypass switch and it would start running again as should so all I use now is direct without that resistor. And no problems with points burning. The John Deere B and Farmall H both with 6 volt systems never has a resistor in them as neither did the 49 Chevy truck and never any points burning. Just put back 6 volt coil and good 6 volt battery and get rid of any resistor and it should be running good. A few years back was having discussion this subject and John T the electrical enginer did not realize that could work untill I told him how it was working for me. That resistor was the problem with all the 6 volt Ford cars running problems as well as the tractors never ran as good from new as after that resistor was gotten rid of. The 8 volt with a resistor put a bit over 6 volts to tractor to get it to start. I have both a 41 9N and a 44 2N bought new in may of 44. If I was looking for a tractor a 12 volt conversion would tell me to skip it.

"Ford used a resistor to cut the 6 volt down to 4.8 volt thinking points would burn with higher voltage. "

Leroy, "VOLTS" typically don't "burn" ignition points, it's the increased CURRENT that is caused by increasing the supply voltage.

Coils are not created equal, and an OEM 2N coil has a very low primary resistance vs. many other 6 Volt coils as used in other manufacturer's products.

As to modern replacement coils for the "front-mount distributors, apparently their resistance can vary widely from one to another or to the original OEM coil.

The purpose of the ballast resistor is to add resistance to the primary circuit, limiting current through the points.

A commonly accepted primary current upper limit for long point life is about 4 Amps.

Accurately measuring the primary CURRENT is a far more accurate way of determining if more or less primary resistance is needed that an Voltage check.

Lots of anecdotal evidence about all this, such as yours, but a simple Amperage test will "tell the tale".