generator

[pett3227b]

the battery is definitley 12 volt and i have been using it for 20 years. I am told it would still run the cub if my system is 12 or 6 volt. Does anyone know if I could put a voltage regulator on the wire for the headlights and see what voltage I get? I am told the wire to my headlights is working I need to know if a 6 volt generator would put 6 volts to the lights and a 12 volt generator would put 12 volts to the lights. I thought I read somewhere that it would. Also if this Idea would work which light switch position would test on the dim position or the high position.

[Glen]

Hi,
The Cub magneto with the original style internal coil, under the cover on top of the magneto, makes it's own power.
The magneto is a unit that makes it's own power. It is not connected to any battery power.
The magneto doesn't need changing from 6 to 12 volts. Do not connect any battery to it.

The light wires for the front lights would have whatever voltage the battery is, in the wires, whenever you turn the light switch to the Bright position.
In the Dim position the front wires will have slightly less voltage, that is how the switch dims the front lights.
The rear light would have battery voltage with the switch turned to Dim or Bright, the rear light does not dim.
Read my 1st post on page 1 of this post, with the 2 pages from the Cub owner's manual, it tells how to use the light switch.

[pett3227b]

The battery is a 12 volt. I purchased it about 3 years ago. I have been running a 12 volt battery on this tractor for over 20 years and has been running just fine. I am not any closer to determining if my generator is 6 or 12 volt. The serial number confirms that originally it was a 6 volt generator. The pictures show that there has been some work done on the electrical system. The relay has been moved. I was told that the cub could still operate with a 12 volt battery even if the system is 6 volt. Though there could be fire danger. Im out of ideas as to how to determine if 12 or 6 volt system. Could I take the generator somewhere and have it tested? Like the kind of place that might rewire these things to convert to 12 volt. Or is there somewhere I could attach a voltmeter while the tractor is running?

[Clemsonfor]

I was about to say, can't you attach a voltmeter to a few places and check the output voltage? I am not a 6v or generator specialist but I know you can test the output.

[Glen]

Hi,
Yes, you can use an automotive test voltmeter on the system, connected at the battery.
They have said on here that a tester with a dial and pointer works better for a Cub.
People have used digital display testers and they say it just shows the voltage going up and down, they couldn't get any accurate reading.
I don't know if you said if the Cub's ammeter ever shows any charge.

Or you could call a shop that rebuilds starters and generators and ask them if they can test a gen to see what voltage it is. Then you would need to take the gen to them.

Or you could buy a 6 volt battery, put in the battery box, connect it positive ground, like the system originally was, and run the engine and test the generator output.
If you do that, the ammeter on the Cub should show what the gen is doing also, if the ammeter is connected.
If the voltmeter shows readings up at 13 or 14 volts, the gen may have been changed internally.
Since the Relay, or voltage regulator, whichever it is has been moved to on the engine, it may not be connected so the charging system works.

The battery posts are different sizes.
If the 12 volt battery is negative ground now, to change it to 6 volts positive ground, you will need to open the negative cable end some so it will go on the positive battery post.
The 6 volt battery that fits in Cub battery boxes is a Group 1.
The battery goes in the box with the positive post forward.
NAPA and other auto parts stores sell them.

[pett3227b]

My ammeter is not currently working. I am wondering if I could connect a voltmeter at the battery with tractor off and of course it would show 12 volts. If I were to then crank the tractor would I see a spike in voltage? Would I see a spike in voltage if the gen was a 6 volt system? Which headlight setting would I set to? HIgh charge or low charge?

[pett3227b]

Consisdering that the ammeter is out and I don't know yet about the relay. could I connect the alligator clips directly to the gen then crank the tractor? Or should I do this in both places at the gen and at the battery to see if wiring or relay between the gen and battery are a problem?

[Eugene]

Consisdering that the ammeter is out and I don't know yet about the relay.

6 volt system, 12 volt battery, the cutout (relay in your terms) will not function. If the battery voltage is higher than the generator output voltage the cutout opens up - - disconnects the generator from the battery.

True even if the electrical system has only the cutout or the cutout portion of a regulator.

The needle portion of the amp meter is not be functioning. However, electrical current may be passing through. Check for battery voltage on the cutout/regulator side of the amp meter.

My suggestion, 12 volt single wire alternator,

[Clemsonfor]

My ammeter is not currently working. I am wondering if I could connect a voltmeter at the battery with tractor off and of course it would show 12 volts. If I were to then crank the tractor would I see a spike in voltage? Would I see a spike in voltage if the gen was a 6 volt system? Which headlight setting would I set to? HIgh charge or low charge?

As you crank an engine the battery will drop in voltage. But even charging it won't spike it above 12.6v because a 6v generator probably won't put out more than 7 to 8v peak.

[Eugene]

Red Delco generator tag = 12 volts. Black tag = 6 volts. Your tag appears to be red.

Look up the Delco generator tag colors on the internet.

[Glen]

Hi,
Eugene, in his 1st pic showing the generator plate on page 1 of this post, part of the generator ID plate looks redish, and part of it on the left looks black. It might be just the picture or camera flash, making it look redish.
The model number he gave at his first post is an original Cub 6 volt gen, 1101355, for use with the Relay on top of it.
The model number is in the table on page 1, that Bill V in Md posted, it shows it is a 6 volt gen.

pett3227b, if the part on the engine has connections for 4 wires, it is a voltage regulator, which came out on Cubs during 1950. If it has 4 posts, someone has changed it from the original Relay that was on top of the generator. The Relays have 3 posts for wires, and a curved bottom that fits on the shape of the gen.

The 4 position switch is not used with the voltage regulator. The switch is only a light switch if the tractor has a voltage regulator.
When IH changed to the reg in 1950, they used a 3 position light switch, with O off, D dim, B bright, positions.
I think the L and H positions on the 4 position switch can both be Off for the lights, when the switch is used for only the lights. That is how they are when converting a Cub to 12 volts with an alternator.
The voltage regulator chooses which charge rate to charge the battery.

If it is a voltage regulator, I suggest you move it to the position IH put them, which is beside the generator, on a plate.

Below is a page from the 1955 Cub operator's manual, showing it.

http://farmallcub.com/rudi_cub/www.clea ... e%2050.jpg

TM Tractor has a new mounting plate, below is their listing.

http://www.tmtractor.com/new/el/952fp.htm

The page below shows the reg mounted on the plate, in the upper right pic.

http://farmallcub.com/rudi_cub/www.clea ... e%2049.jpg

The plate goes on the gen mounting bracket bolts. It goes under the gen bracket, and the curve faces down, so the top of the reg doesn't hit the side of the hood.

Or if you want it original, you could buy a new Relay, and put it on top of the gen, and use the 4 position switch to choose the charge rate. It would have to be wired right for the Relay.

[Eugene]

Thanks Glen. I really haven't been following this topic. So, I went back and read some of the posts.

In any event, I don't know why the tractor owner has been starting the tractor with a 12 volt battery for 20 years. My guess, starter dragging when trying to start on 6 volts. Perhaps the owner will explain.

Another thought, magneto. Purchase a hand crank and forget the battery powered starter. Hand crank, cheaper than installing a 12 volt alternator.

Edit. I blew the photo of the generator tag up. Doesn't look like flash, looks like red paint. Also couldn't read the serial number.

[Clemsonfor]

Thanks Glen. I really haven't been following this topic. So, I went back and read some of the posts.

In any event, I don't know why the tractor owner has been starting the tractor with a 12 volt battery for 20 years. My guess, starter dragging when trying to start on 6 volts. Perhaps the owner will explain.

Another thought, magneto. Purchase a hand crank and forget the battery powered starter. Hand crank, cheaper than installing a 12 volt alternator.

Edit. I blew the photo of the generator tag up. Doesn't look like flash, looks like red paint. Also couldn't read the serial number.

He gave us the serial # so unless he read it wrong we have that . And what I remember is that he bought the tractor with a 12v battery, I could be remembering wrong though. Another question is do they have it hooked up positive ground even?

[pett3227b]

I will look at the voltage regulator or relay and determine how many wire there are. I will also call some people and see if they could test the generator and tell me if it is 6 or 12 volt. I am considering replacing the coil that I have. I am told that it doesn't matter if the system is 12 or 6 volt to replace the coil. That is unless once again that it has been converted internally. Comments here would be a help. If i put a new coil in the magneto are there things that I need to take into account if i need to convert to 12 volt later on? taking into account that I may have a 6 or 12 volt tractor.

[Rick Spivey]

Magneto voltage has NOTHING to do with tractor voltage, they are independent. Replace the coil if your spark is missing or weak, otherwise the magneto coil is likely fine.