did the 12v conversion with the kit I got from YT

The wiring diagram is a little hard to read. When connecting to the alternator with a single wire do I use the bat terminal or do I use the r terminal on the alt. Also, do I use the 6v white resister I got to replace the old black resister a couple of years ago?
 
A 3 wire conversion is easy.
Click on the link for a very simple diagram on how to do it.
If you have a front mount didtributer I would gut the coil and go with a round can 12V coil that doesn't need a resister.
If side mount replace the 6V coil with a 12V coil that doesn't need a resister.
Ultimately it's less parts, less wiring and connections and more long term reliability.
scroll down towards the bottom.
 
Your question ".... do I use the 6v white resister I got to replace the old black resister a couple of years ago? "

and the fact that you do not have spark tells me that it's very likely that you have burned up a coil by trying to figure out what resistor to use.

Check out tip # 30.

All you need is the OEM ballast resistor and a 12 volt coil (a front coil with at least 2.5 ohms of internal resistance )

That's it. No other resistors.

As to no spark......

Assuming that the bushings & advance weights are ok (*see below), & that you have correct voltage to the coil (battery voltage with the points open and about half that with the points closed), the most common electrical failure (no spark, weak spark) points on the front mount are:

1. The insulator under the brass concave head screw & where the copper strip attaches. (it’s fiber & will wear out; poke & prod w/ your meter leads to make sure it still works) If you need to replace the insulator, use a .250 x 3/8 nylon square nylon anchor nut available at most big box home stores

2. The pigtail at the bottom of the coil not making contact w/ the concave head brass screw inside the distributor. (With the coil on, the pigtail must firmly contact the brass screw. No contact = no spark

3. The copper strip is broken or grounded to the plate. (look very carefully for cracks & breaks).

4. The condenser wire grounding to the plate or side of the distributor.

5. The tab on the bottom of the coil not making contact w/ the brass button on the cap. (With the cap on, the tab must firmly contact the brass button. No contact = no spark.)

6. Incorrect positioning of the spring clip on the plate causing the pigtail to ground. (the open part of the clip goes between 7 & 9 o’clock on the plate. That puts the straight part of the clip opposite of the timing screw at 3 o’clock)

7. Incorrect seating of the coil on the distributor due to a loose bail or no gasket.(the coil must not move at all; if it does, replace the gasket or bail. Or stick some cardboard under the bail).

8. Water/moisture inside the cap due to gasket failure or the absence of a gasket. (the cap AND coil have gaskets)

9. Dirty/corroded/burned/incorrectly gapped or misaligned points. I use only Wells, Blue Streak or Echlin brand points (* *see below).

10. Burned rotor, cracked/carbon tracked cap.

At this point, I just put the distributor, coil & cap all back on the tractor as a unit. The reason I do this is because it is real easy to get the cap or coil misaligned trying to put it back together, one piece at a time. The result is something gets broken or you get a ‘no spark’ problem.

It's possible to put it back on wrong & break it. Look at the slot on the end of the cam shaft. Whatever angle it happens to be, turn the distributor tang to match it. Make sure you can tell the wide side from the narrow side on both the cam & distributor! (close counts). Place the distributor on the front of the engine, gently push it in place & slowly turn the distributor body until you feel the tang slip into the slot. Rotate the distributor body until the bolt holes line up. Hand tighten the two bolts until the distributor body is flush with the timing gear cover.

Post back w/ results or more questions.


* Unscrew the plate hold down screw & remove the C clip to get the plate out. Remove the shaft & weights. The weights should freely move.


* *NAPA part numbers:

• Points: FD-6769X
• Condenser: FD-71
• Rotor: FD-104
• Cap: FD-126
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75 Tips
 
the wiring diagram in the kit I got from here says to use a white resister that comes with the kit and the black resister that was on the tractor. I replaced the black resister with a white one a few years ago.

I've ordered the black resister and a new coil. I'll see if that works....I'll also bring my Fluke meter this time
 
" I replaced the black resister with a white one a few years ago"

Did you determine the resistance of that "white" resistor before you put it on the tractor?

It's very easy to get too much resistance in the ignition circuit. Just randomly replacing resistors w/o measuring them will get you a burned up coil or a poorly running tractor.

Technology & materials being what they were in the 30's, that square coil would melt if it ran on much more than 4 amps for any length of time. (see tip # 38 for an example). In order to get a hot spark at the same time the starter was drawing max current from the battery, a ballast resistor was added in the ignition circuit. What that did was add about .3 ohms of resistance in the circuit, added to the 1.5 ohms of the coil. That got you 3.5 amps or so at start up. As the voltage increased when the engine was running to about 7.5 volts, the resistor heated up, adding more resistance in the circuit. 1.0 ohms hot, plus 1.5 ohms of the coil got you down to 3 amps or so to keep from melting the coil. The same rule (actually, Ohm's Law) applies to a 12v circuit. I= E/R. Current equals voltage divided by resistance.

Those "white" resistors are not ballast resistors. They are fixed resistors. And no telling what they measure.
75 Tips
 
No, I didn't check resistance on the replacement. I just went to my local New Holland dealer in Palestine Tx and asked for a replacement at the parts counter. They gave me the white one
 
(quoted from post at 13:36:53 08/01/14) No, I didn't check resistance on the replacement. I just went to my local New Holland dealer in Palestine Tx and asked for a replacement at the parts counter. They gave me the white one
ike Bruce said, a "white ceramic" resistor can be just about anything.........have personally seen these range from 0.35 to 2.0 Ohms! FAR TOO wide a range to expect good results with just any one pulled out of the basket!
 
Ok.. I finally got a chance to work on it again. Installed one black resister and new 12v coil. Following all 12v conversion wiring diagrams I could find I left the white resister between black resister and coil. I fired right up but was missing a little bit.

Hooked up bush hog and mowed a little but tractor strained when I got to the thick stuff.....it then as stalled and wouldn't start til it cooled down 15-20 minutes later.

I've triple checked wiring, points setting .015 and even pulled carb and cleaned it up.

The distributer seems to have a little play in the bushings. Does this sound like the culprit?

Any opinions on the electronic ignition conversion?
 
So, did you misunderstand what I said, and what JMOR said, or are you simply ignoring our advice?

You said " Following all 12v conversion wiring diagrams I could find I left the white resister between black resister and coil."

My previous advice to you was: " Check out tip # 30. All you need is the OEM ballast resistor and a 12 volt coil (a front coil with at least 2.5 ohms of internal resistance ) That's it. No other resistors. "

So you now have installed 2 resistors of who knows what values (black and white are not values) and now your tractor does not run.

And you are asking why.

" The distributer seems to have a little play in the bushings. Does this sound like the culprit?"

No, that did not cause it not to re-start, but you will need to replace them for it to run correctly.

I also gave you 10 common failure points on a frontmount distributor. Have you checked any of them yet?

" Any opinions on the electronic ignition conversion? "

Sure. Go ahead & spend another $130 and then you will have a tractor w/ EI that doesn't run either. You'd be well served to get it running on points first & make that EI call later.

I'm a married man, so I'm used to being ignored. But if you want the tractor to run, I'd suggest that you pay attention to what JMOR & I are telling you.
75 Tips
 
2 resistors and 12v coil?

sounds like you don't follow directions very good...

(quoted from post at 09:31:46 08/17/14) Ok.. I finally got a chance to work on it again. Installed one black resister and new 12v coil. Following all 12v conversion wiring diagrams I could find I left the white resister between black resister and coil. I fired right up but was missing a little bit.

Hooked up bush hog and mowed a little but tractor strained when I got to the thick stuff.....it then as stalled and wouldn't start til it cooled down 15-20 minutes later.

I've triple checked wiring, points setting .015 and even pulled carb and cleaned it up.

The distributer seems to have a little play in the bushings. Does this sound like the culprit?

Any opinions on the electronic ignition conversion?
 
(quoted from post at 14:22:16 08/17/14) So, did you misunderstand what I said, and what JMOR said, or are you simply ignoring our advice?

You said " Following all 12v conversion wiring diagrams I could find I left the white resister between black resister and coil."

My previous advice to you was: " Check out tip # 30. All you need is the OEM ballast resistor and a 12 volt coil (a front coil with at least 2.5 ohms of internal resistance ) That's it. No other resistors. "

So you now have installed 2 resistors of who knows what values (black and white are not values) and now your tractor does not run.

And you are asking why.

" The distributer seems to have a little play in the bushings. Does this sound like the culprit?"

No, that did not cause it not to re-start, but you will need to replace them for it to run correctly.

I also gave you 10 common failure points on a frontmount distributor. Have you checked any of them yet?

" Any opinions on the electronic ignition conversion? "

Sure. Go ahead & spend another $130 and then you will have a tractor w/ EI that doesn't run either. You'd be well served to get it running on points first & make that EI call later.

I'm a married man, so I'm used to being ignored. But if you want the tractor to run, I'd suggest that you pay attention to what JMOR & I are telling you.
75 Tips


It's simple. If you have too much resistance the coil will not get enough power to run properly producing weak spark resulting in missing, low power and hard starting. There are several members here who have forgotten more about N series electrics than many people know. But they are all very old and cranky (teasing) and snap at people. I think Bruce was there to tell ole Ben Franklin to put a tail on that kite......BUT THEY KNOW WHAT THEY ARE TALKING ABOUT. If you follow their advice you will save time, money a aggravation.

Bruce while a little abrupt and the OP may not respond ever again that's the best reply I've seen in a long time!

Rick
 
Tnx Rick.

" OP may not respond ever again", well, not my intent, but some of the best learning I ever had was preceded by "Get your head out of your fourth point of contact and listen up, troop!".

First Sergeants have a way with words that clears out the cobwebs & allows you to FOCUS on the topic at hand.
 
I'm not ignoring Bruce I just can't figure out
why the kit I got from Yesterday's Tractor had the white resistor if I'm not supposed to use it. The wiring diagram that came with the kit shows the white resister in between OEM black resister and 12v coil that came with the kit. I looked at a few wiring diagrams for 12v conversions and they show the same thing.

I was getting spark on #3 with an old plug gapped about 1/4" but it wasn't consistent.

I'll get some bushings and redo the distributer and take out the white resister and all will be well
 
" I just can't figure out"

Then we must not be explaining it very well. The additional resistor of an unknown value puts too much resistance in the circuit. The result is a weak spark.

" I looked at a few wiring diagrams for 12v conversions and they show the same thing."

Sure.....if the 12 volt conversion is using the OEM 6 volt coil. Then another resistor is required. That or the diagram is simply wrong.

Google "wiring diagrams JMOR". You will not find two resistors in any of his diagrams w/ a 12 volt coil.

" I was getting spark on #3 with an old plug gapped about 1/4" but it wasn't consistent."

Because.....and you should be able to tell us the answer now......you have a weak spark due to too much resistance in the ignition circuit.

" I'll get some bushings and redo the distributer "

Ever done that before?

There are three ways to replace the bushings in a front distributor:

1.Buy new bushings (part numbers 9N12120 front & 18-12132 rear). Press out the old ones, press in the new ones and ream to fit. CAUTION: do not try this unless you have a press & know how to use it. If you break the base, a new one costs $130. If you bend the tower which holds the front bushing, a new plate will cost you $30.

2.Take the new bushings and distributor to your local machine shop.

3.Send the distributor out for bushing replacement if you do not have a local machine shop.

Post back w/ results or more questions.
75 Tips
 
(quoted from post at 10:27:26 08/18/14) Tnx Rick.

" OP may not respond ever again", well, not my intent, but some of the best learning I ever had was preceded by "Get your head out of your fourth point of contact and listen up, troop!".

First Sergeants have a way with words that clears out the cobwebs & allows you to FOCUS on the topic at hand.

Bruce, I've said that many times between 76 and 96, that's the years I was an NCO. I just never said it in such a polite manner :shock: :lol: :twisted: !!!

Rick
 
put the wrenches down, and take a deep breath.
When you find yourself in a hole, first thing is to stop digging.

Your tractor runs, sorta, so leave the distributor alone for now.
Wiring is a bunch of subsystems that usually have nothing to do with each other, all taped together....
So, take care of ignition first.
You have a 12v square coil in hand, so like Bruce has said a couple times,
power from the key switch, thru the [b:d5c503bf12]OEM ballast resistor[/b:d5c503bf12], then to the coil. That's it, ignition power is done.
(throw those white block ones in the trash and find a new dealer if they gave you one to replace a ballast resistor)
Only then, with a good running tractor, wire in your alternator
with its directions depending on what style it is.
(and remember...subsystems.... since you now have your ignition ready for 12v with the above wiring and 12v coil, the kits directions for ignition do not apply to you. Like Bruce said, they are for a stock 6v coil setup)

ps and a me too on 12v fronts, after you get everything right with what you have, research and study posts about converting a square coil to a round coil. When you understand it, do it with a 12v round no-resistors-needed coil, and throw that square coil and ballast resistor in the trash right next to the block resistors.
:)
 

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