TO20 12v conversion wiring

I've recently been restoring my TO20. I had someone helping me re-do wiring and they didn't keep track of how it was wired before. It does have a 12 volt conversion. I have everything figured out except the 2 wires from the alternator. I assume 1 goes to the ammeter and one goes to the battery or starter switch to charge? Any help would be greatly appreciated. I've looked at all.of the wiring diagrams but nothing seems to match the setup I have.

Thank you in advance.
 
You can attach the alt to battery wire to the hot side of the start switch and yes the other goes to the ammeter. If you find negative charge
on ammeter swap posts.
 
(quoted from post at 10:51:44 04/15/22) You can attach the alt to battery wire to the hot side of the start switch and yes the other goes to the ammeter. If you find negative charge
on ammeter swap posts.

Thank you so much. This might be a stupid question but where does the lead coming off of the ammeter go?
 
of you have a smart phone you can enlarge the picture..
mvphoto90755.jpg
 
The diagram is not clear on the complete wiring of the alternator.

You will need to get the harness connector plug, it's available at any auto supply.

Also get a through wired lamp socket for the warning light. You don't have to have the light visible, it can be taped out of sight. The light is necessary though, it serves as a resistor.
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That diagram I gave you is for a to30, its from the last kit I got, which includes a resistor. Steve is right you will need somthing to cut the voltage to 6 before it gets to the coil.
 
(quoted from post at 19:18:38 04/15/22) That diagram I gave you is for a to30, its from the last kit I got, which includes a resistor. Steve is right you will need somthing to cut the voltage to 6 before it gets to the coil.

I did buy a 12v coil, shouldn't need anything to cut the voltage to 6, right?
 
I think youll be fine, but it will decrease the life of your points and condenser, unless you go with electronic ignition as well.
 
Here is a basic diagram for Delco internal regulated 3 wire alternator. You can use a 194 lamp or 10 ohm 10 watt resistor in place of the diode. Purpose is to prevent engine from continuing to run when switch is turned off. Should be easy to adapt to your situation.

#1 edge pit is to excite the alternator to start charging when engine is started. #2 is to sense and control charge of the battery

cvphoto123267.jpg
 
Looking close, this sheet appears to be for a 1 wire alternator. Other instructions in this discussion have been for 3 wire.

Resistor is used with 1 1/2 ohm resistance primary 6 volt coil. Do not use with a direct 12 volt No external resistor required coil with 3 ohm resistance primary.
 
K. Campbell wrote: I think youll be fine, but it will decrease the life of your points and condenser, unless you go with electronic ignition as well.
Not true, he has a 12 volt coil, same current flow across the points as a 6 volt coil.
 
My resistors on both of my 30s are right before the coil. I was told by the local mechanics years ago, before these kits were available that the reason the resistor was before the coil, was that the condenser and points wouldnt last as long with 12 volts flowing through as it would with 6. I know that many of the ac Delhi could have built in resistors I figured that was the reason for that as well? I could be wrong I spose.
 
Smart phones, don't we love them? I think you hit the nail on the head. It depends on if the 12 volt coil is meant for an external resister or not.
 
(quoted from post at 12:31:51 04/16/22) Looking close, this sheet appears to be for a 1 wire alternator. Other instructions in this discussion have been for 3 wire.

Resistor is used with 1 1/2 ohm resistance primary 6 volt coil. Do not use with a direct 12 volt No external resistor required coil with 3 ohm resistance primary.

If his 12 volt coil doesn't say FOR EXTERNAL RESISTOR, He's good to go as is.
 

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