Farmall Cub Electrical

I just pulled in a 1953 FCub that I was going through and getting in shape this evening. I noticed that this tractor has a 6V distributor ignition. As I was cleaning up the wiring on the battery and removing the corrosion I noticed that the negative was to ground and positive was to the starter. I thought all of the earlier machinery was positive ground. It will start with the negative ground but what is the correct set-up? If I swap the grounds do I need to make any other circuit changes?

Thanks in Advance
CT
 
I guess if it aint broke dont fix it, but that being said:

For one the coil is polarity sensitive so if youre now at neg ground the coils lil + wires to the ignitiion switch while its other lil - wires to the distributor (it was opposite that at Pos ground). It will still work either way but BETETR if wired correct

If originally Pos ground (like most 6 volt early IHC) and it has a working ammeter its leads would have to have been swapped otherwise it will read bass ackwards i.e. show charge when its really discharging and show discharge when its really charging

If you change battery polarity the genny would need re polarized to work correctly.

SOOOOOOOOOOO

Is it charging okay now???

Have an ammeter and is it working correct?

Is the coil wired correct (to match your ground) ?

Fer as I know it was original 6 volt Pos ground so if you wanna go back,

Reverse battery,,,,,,,POLARIZE GENERATOR,,,,,,,,,Check any ammeter leads if they need reversed or not,,,,,,,,,,,Wire the coil as noted above (if needed)

John T
 
(quoted from post at 12:51:03 08/15/09) I guess if it aint broke dont fix it, but that being said:

For one the coil is polarity sensitive so if youre now at neg ground the coils lil + wires to the ignitiion switch while its other lil - wires to the distributor (it was opposite that at Pos ground). It will still work either way but BETETR if wired correct

If originally Pos ground (like most 6 volt early IHC) and it has a working ammeter its leads would have to have been swapped otherwise it will read bass ackwards i.e. show charge when its really discharging and show discharge when its really charging - [b:ad08da47c8]John T - When I turn the lights on, the ammeter needle goes to the charge side of the gage. This tells me the leads are incorrect.
[/b:ad08da47c8]
If you change battery polarity the genny would need re polarized to work correctly.

SOOOOOOOOOOO

Is it charging okay now??? [b:ad08da47c8]Not sure !![/b:ad08da47c8]

Have an ammeter and is it working correct? [b:ad08da47c8]Yes have an ammeter but with lights turned on the meter goes to the charge side of the filed.[/b:ad08da47c8]

Is the coil wired correct (to match your ground) ?

Fer as I know it was original 6 volt Pos ground so if you wanna go back,

Reverse battery,,,,,,,POLARIZE GENERATOR,,,,,,,,,Check any ammeter leads if they need reversed or not,,,,,,,,,,,Wire the coil as noted above (if needed)

John T
u:ad08da47c8][i:ad08da47c8][/i:ad08da47c8][/u:ad08da47c8]
 
Okay, when not running if you turn lights on she swings to + charge THE AMMETER IS BACKWARDS probably cuz it was originally pos ground but got switched to neg ground and no one reversed ammeter leads.

If its charging when running at fast RPM with a backwards ammeter (like you have) it would swing over to - discharge THAT WILL TELL IF ITS CHARGING OR NOT even tho ammeter may be backwards

Measure battery voltage just setting it should be around 6.3 volts for a 6 volt or 12.6 for a 12. Then when running at fast RPM if shes charging the battery voltage will rise to the 6.5 to 7 or so range, twice that on a 12 volt system.

Heres how to troubleshoot non charging

http://www.ytmag.com/cgi-bin/viewit.cgi?bd=farmall&th=665110

John T
John Ts Troubleshooting
 
(quoted from post at 17:46:56 08/15/09) Okay, when not running if you turn lights on she swings to + charge THE AMMETER IS BACKWARDS probably cuz it was originally pos ground but got switched to neg ground and no one reversed ammeter leads.

If its charging when running at fast RPM with a backwards ammeter (like you have) it would swing over to - discharge THAT WILL TELL IF ITS CHARGING OR NOT even tho ammeter may be backwards

Measure battery voltage just setting it should be around 6.3 volts for a 6 volt or 12.6 for a 12. Then when running at fast RPM if shes charging the battery voltage will rise to the 6.5 to 7 or so range, twice that on a 12 volt system.

Heres how to troubleshoot non charging

http://www.ytmag.com/cgi-bin/viewit.cgi?bd=farmall&th=665110

John T
John Ts Troubleshooting

Thanks John,
I will get into it tonight. Will post results later. I don't think it is charging because at high rpm idle the needle of the ammeter is at dead center.
Tim
Tim
 

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