We bought a 1949 W4 at a auction on SUnday. It has a mag and no lights.It has a 12V battery. It has the 4 pos light sw. There is a VR with 2 term. 1 being the 12V(B) and a smaller wire going to the Gen. The Gen has 2 term.I wonder if they just installed a 12V batt and left the 6V gen and reg in place,I cant find any marking on the Gen it does not have the old adjustable pulley on it. I just wonder where I start to find out what we have. Thanks
Janicholson
Well-known Member
- Location
- Central MN St. Cloud
Someone just dropped a 12v battery in it.
The light switch has control of generator output.
It does this by grounding the small F terminal of the generator through the switch to the electrical box metal. When the F terminal is grounded, the Generator is full charge.
The switch (really the operator) when set to L (full CCW)is a low charge setting. The ground for the Gen goes through a resistor on the switch of about 1.5 to 2 ohms, and then to ground through the switch body.
This "reduced" ground, reduces the field current, reducing the gen output so that it just trickle charges the battery.
On H position (one click CW) the F terminal on gen is direct grounded. Gen puts out max charge.
(this is used when the tractor has just been started, and the battery needs to be recharged) usually for 20 minutes to 40 minutes depending on how much cranking was done to get it started.
Once charged the operator then turns it back to L.
When on D or B the lights are on. In this position the gen output is also full ground max output.
The VR you describe is actually a cutout relay.
It is connected to the amp gauge load side, and from there, to the starter terminal cable nut, and from there (originally) to the battery negative terminal. The other yterminal on the cutout should be attached with a similar 10 gauge wire to the generator's bigger (A) terminal
(it might say ARM at the terminal on the gen).
The Cutout relay has only one purpose, it is to disconnect the generator from the system at all times it is not producing enough voltage to charge or maintain the battery. This includes when at low idle, lights on or off, and when the tractor is shut off.
There is no connection between the mag and the charging starting or lights at all. The mag wire is a grounding wire that shorts out the mag to grouns to stop the rngine. Make no connections to power, the mag makes its own electricity.
The attached diagrams are from Bob M. The #4 diagram is for your attention.
It is a 6 volt tractor with positive ground.
Best of luck, and ask us for help as needed. JimN
Bob M diagrams of high value
The light switch has control of generator output.
It does this by grounding the small F terminal of the generator through the switch to the electrical box metal. When the F terminal is grounded, the Generator is full charge.
The switch (really the operator) when set to L (full CCW)is a low charge setting. The ground for the Gen goes through a resistor on the switch of about 1.5 to 2 ohms, and then to ground through the switch body.
This "reduced" ground, reduces the field current, reducing the gen output so that it just trickle charges the battery.
On H position (one click CW) the F terminal on gen is direct grounded. Gen puts out max charge.
(this is used when the tractor has just been started, and the battery needs to be recharged) usually for 20 minutes to 40 minutes depending on how much cranking was done to get it started.
Once charged the operator then turns it back to L.
When on D or B the lights are on. In this position the gen output is also full ground max output.
The VR you describe is actually a cutout relay.
It is connected to the amp gauge load side, and from there, to the starter terminal cable nut, and from there (originally) to the battery negative terminal. The other yterminal on the cutout should be attached with a similar 10 gauge wire to the generator's bigger (A) terminal
(it might say ARM at the terminal on the gen).
The Cutout relay has only one purpose, it is to disconnect the generator from the system at all times it is not producing enough voltage to charge or maintain the battery. This includes when at low idle, lights on or off, and when the tractor is shut off.
There is no connection between the mag and the charging starting or lights at all. The mag wire is a grounding wire that shorts out the mag to grouns to stop the rngine. Make no connections to power, the mag makes its own electricity.
The attached diagrams are from Bob M. The #4 diagram is for your attention.
It is a 6 volt tractor with positive ground.
Best of luck, and ask us for help as needed. JimN
Bob M diagrams of high value
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