Ford 2N 12 volt conversion - only 6 volts at battery!

Hello! We are working on an early 2N tractor that someone else did a 12 volt conversion on.

We fixed the fuel system. Carb rebuilt, fuel tank cleaned out.

The tractor now starts/runs great. The problem is that while running, measuring voltage at the battery posts is only 6 volts!

After running two to three minutes, the tractor dies.

Still learning electrical on these 6v/12v systems -- thanks!
 
(quoted from post at 17:09:24 05/11/16) Hello! We are working on an early 2N tractor that someone else did a 12 volt conversion on.

We fixed the fuel system. Carb rebuilt, fuel tank cleaned out.

The tractor now starts/runs great. The problem is that while running, measuring voltage at the battery posts is only 6 volts!

After running two to three minutes, the tractor dies.

Still learning electrical on these 6v/12v systems -- thanks!
f killing a 12v battery in two or three minutes, then some wires ought to be very hot or smoking unless you began with a near dead 12v battery. I can't help you much without knowing how it is wired and what alternator you are using. Shade tree Jack wires these things in dozens of different ways. Amazingly many work.
 
(quoted from post at 14:16:23 05/11/16)
(quoted from post at 17:09:24 05/11/16) Hello! We are working on an early 2N tractor that someone else did a 12 volt conversion on.

We fixed the fuel system. Carb rebuilt, fuel tank cleaned out.

The tractor now starts/runs great. The problem is that while running, measuring voltage at the battery posts is only 6 volts!

After running two to three minutes, the tractor dies.

Still learning electrical on these 6v/12v systems -- thanks!
f killing a 12v battery in two or three minutes, then some wires ought to be very hot or smoking unless you began with a near dead 12v battery. I can't help you much without knowing how it is wired and what alternator you are using. Shade tree Jack wires these things in dozens of different ways. Amazingly many work.

I can smell something very warm around the ceramic white aftermarket resistor.

It looks like this is a 3 wire alt....delco remy 1100241 66A
 
Depending on coil, you generally need that resistor plus the standard Ford 12250 resistor, but lack of one won't kill a good battery that fast. Does the alternator get hot?
 
I can run my 6V tractor or my 12V tractor without the charging system working all day. Just recharge when needed.
To run a tractor on 6V basically all you need is the battery going to the so called 'Infamous Ballast resistor' then to the coil.
12v add to that another resistor to drop the volts back down to 6v if going to a 6v coil.
If it has a 12v coil, skip the second resistor.
Thing about these coils is they are not labeled as to what they are.
Course you also have the starter, key switch and such in there too. But they don't make an engine run.
Why you have a 12v battery that shows only 6v is a mystery?
What does it show when fully charged?
 
(quoted from post at 16:09:24 05/11/16)
The tractor now starts/runs great. The problem is that while running, measuring voltage at the battery posts is only 6 volts!

After running two to three minutes, the tractor dies.

Are you using a digital meter for this measurement? They don't like the noise on these tractors.

What is the battery voltage after the tractor dies? If it's normal, I doubt your problem is electrical. Two to three minutes sounds more like a fuel starvation problem.
 
(quoted from post at 20:09:40 05/11/16) I can run my 6V tractor or my 12V tractor without the charging system working all day. Just recharge when needed.
To run a tractor on 6V basically all you need is the battery going to the so called 'Infamous Ballast resistor' then to the coil.
12v add to that another resistor to drop the volts back down to 6v if going to a 6v coil.
If it has a 12v coil, skip the second resistor.
Thing about these coils is they are not labeled as to what they are.
Course you also have the starter, key switch and such in there too. But they don't make an engine run.
Why you have a 12v battery that shows only 6v is a mystery?
What does it show when fully charged?

What should the resistance be on the second resistor? I tested the resistance on the coil, and it is 1 to 1.1 ohm. I think this means I have a 6v coil. Therefore I think I need a second resistor after the factory ballast resistor.
 
(quoted from post at 07:43:00 05/12/16)
(quoted from post at 16:09:24 05/11/16)
The tractor now starts/runs great. The problem is that while running, measuring voltage at the battery posts is only 6 volts!

After running two to three minutes, the tractor dies.

Are you using a digital meter for this measurement? They don't like the noise on these tractors.

What is the battery voltage after the tractor dies? If it's normal, I doubt your problem is electrical. Two to three minutes sounds more like a fuel starvation problem.

Yes - digital multimeter - cheap one.

Battery voltage before/after running is a solid 12.5 volts.

6 volts when running measured at the posts.
 
the resistor looks like a 12v to 6v one,what is your voltage at top of coil?(when running),have you checked voltage output at alternator? Could be 6 volt
 
(quoted from post at 07:47:27 05/12/16) the resistor looks like a 12v to 6v one,what is your voltage at top of coil?(when running),have you checked voltage output at alternator? Could be 6 volt

I'll check both figures this morning.

Thanks!
 
In this picture, it looks like battery cables going into and out of some sort of resistor. I assume one cable goes to the battery and the other to the starter. If so, I have no clue what the connector thing is for. If it is a voltage reducing resistor, wouldn't that mean you really have a 6 volt tractor? I'm confused!
03E79513-C2BE-4538-90CD-D7079CF22C2A.jpg
 
(quoted from post at 14:53:17 05/12/16) In this picture, it looks like battery cables going into and out of some sort of resistor. I assume one cable goes to the battery and the other to the starter. If so, I have no clue what the connector thing is for. If it is a voltage reducing resistor, wouldn't that mean you really have a 6 volt tractor? I'm confused!

Looks like the starter switch to me :roll:

TOH
 
(quoted from post at 12:04:25 05/12/16)
(quoted from post at 14:53:17 05/12/16) In this picture, it looks like battery cables going into and out of some sort of resistor. I assume one cable goes to the battery and the other to the starter. If so, I have no clue what the connector thing is for. If it is a voltage reducing resistor, wouldn't that mean you really have a 6 volt tractor? I'm confused!

Looks like the starter switch to me :roll:

TOH

Yes this is the factory starter switch.

Ok it's running now, and shuts off as designed when key switch turned to off position.

New problem. Now she won't restart. Dark points.

I'm using factory resistor + a white ceramic ballast resistor.

Ignition coil measured 1.1 ohm. White coil measures???
 
(quoted from post at 12:04:25 05/12/16)
(quoted from post at 14:53:17 05/12/16) In this picture, it looks like battery cables going into and out of some sort of resistor. I assume one cable goes to the battery and the other to the starter. If so, I have no clue what the connector thing is for. If it is a voltage reducing resistor, wouldn't that mean you really have a 6 volt tractor? I'm confused!

Looks like the starter switch to me :roll:

TOH

Not getting spark to plug wires - just checked. Could I not have enough resistance, and messing up coil/points/dist?
 
Measure the resistance on the white ceramic resistor. 1.1 ohms on the coil, 1 ohm for the OEM ballast resistor gets you 2.1 ohms. The ceramic resistor should be 2 ohms or so for a total of 4 ohms in the circuit. 14.5 volts / 4 ohms gets you 3.6 amps running current which is fine.

You should have battery voltage at the top of the coil w/ the points open & something more than half that w/ them closed.

Sounds like your problem is in the distributor if you have no spark w/ battery voltage to the coil.

Assuming that the bushings & advance weights are ok (*see below), & that you have correct voltage to the coil, 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). If you are using quality points and cannot get the gap to open to .015, chances are you need to replace the bushings. If the shaft has any sideways movement AT ALL, the bushings must be replaced.

10. Burned rotor, cracked/carbon tracked cap.

After find the problem & re-check the point gap, do a continuity check before you put the distributor back on the tractor. Before you start, make sure your meter/light works.

With the distributor still off the tractor, follow these steps:

1. Coil off, cap off, points open. One probe on the brass screw & the other on both sides of the open points. On the side closest to the cam, you should have continuity. Not on the other side! If you do, you will also have continuity everywhere because the points are grounded.

2. Coil off, cap off, points open. One probe on the brass screw & the other anywhere on the body of the distributor. You should have no continuity! Now, rotate the tang on the distributor....as the points open & close, you have continuity (closed) and lose it when they open.

3. Put the coil on the distributor, cap off, points open. One probe on the lead on the top of the coil, the other on the cam side of the open points. You should have continuity!

4. Coil on, cap off, points open. One probe on the lead on the top of the coil, the other anywhere on the body of the distributor. You should have no continuity!

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.

* 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
75 Tips
 
You need to determine if it's fuel or electrical and work from there. Although it sounds like an electrical issue, and I would go there first, don't rule out fuel yet. At the moment it dies check for voltage at the coil terminal. Have a voltmeter at the ready and back up from there if you don't have voltage. How does it run when it's running? How long does it take for a restart?
 
(quoted from post at 02:18:25 05/13/16) You need to determine if it's fuel or electrical and work from there. Although it sounds like an electrical issue, and I would go there first, don't rule out fuel yet. At the moment it dies check for voltage at the coil terminal. Have a voltmeter at the ready and back up from there if you don't have voltage. How does it run when it's running? How long does it take for a restart?

We are learning towards electrical at the moment, because no spark from plug wires while cranking.

Carburetor was recently rebuilt, complete with new float. Adjusted correctly I believe.
 
(quoted from post at 02:18:25 05/13/16) You need to determine if it's fuel or electrical and work from there. Although it sounds like an electrical issue, and I would go there first, don't rule out fuel yet. At the moment it dies check for voltage at the coil terminal. Have a voltmeter at the ready and back up from there if you don't have voltage. How does it run when it's running? How long does it take for a restart?

I can get it to almost fire & start if I tweak with the seating of the coil on top of the distributor. The gasket is there in place. When the clamp is on the coil, it sure doesn't secure it very tightly. A little nudge from a finger, and I can move the coil on top of the distributor even with the clamp on.

It won't actually start, but it will sputter instead of just cranking. One time, and it goes back to just cranking with no start or sputter.
 

if the coil is loose on top of the distributor, and it will almost start if u wiggle that around, have u tried arranging a tighter fit there? i'd try cardboard as wedges under the bail (the wire clamp) until it felt snug, and see what happened at that point.
 
(quoted from post at 09:45:22 05/13/16)
if the coil is loose on top of the distributor, and it will almost start if u wiggle that around, have u tried arranging a tighter fit there? i'd try cardboard as wedges under the bail (the wire clamp) until it felt snug, and see what happened at that point.

Ok - I'll try to add a shim under the bail to snug up the fit. Maybe I'm not getting good contact between the metal tab or spiral wire under the coil and the distributor contact points???
 

We sell tractor parts! We have the parts you need to repair your tractor - the right parts. Our low prices and years of research make us your best choice when you need parts. Shop Online Today.

Back
Top