12 Conversion Farmall M

Ok, converted farmall m to 12 volts, starts and runs but when i turn ignition switch off, ammeter shows a slight discharge, once ignition switch is turned off there should be no current going through, after awhile, battery is discharged, what could be the problem if engine starts?

if you did not install a resistor you would have power feeding the alternator causing your battery drain.

(quoted from post at 18:08:49 06/21/14) if you did not install a resistor you would have power feeding the alternator causing your battery drain.

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Ok, that explains everything, did not install a resistor, where do I buy one and what kind?

The lack of a resistor will not cause the battery to discharge with the engine not running. It will prevent the engine from stopping when the switch is turned off.

Assuming you are using a 10SI Delco Remy alternator, check to make sure you have the wire from the battery stud on the alternator connected to #2 terminal and the wire from the ignition switch, through a resistor or diode, connected to #1 terminal. If #1 terminal on the alternator stays hot when the engine is not running it will drain the battery.

(quoted from post at 19:25:37 06/21/14) The lack of a resistor will not cause the battery to discharge with the engine not running. It will prevent the engine from stopping when the switch is turned off.

Assuming you are using a 10SI Delco Remy alternator, check to make sure you have the wire from the battery stud on the alternator connected to #2 terminal and the wire from the ignition switch, through a resistor or diode, connected to #1 terminal. If #1 terminal on the alternator stays hot when the engine is not running it will drain the battery.

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Ok, thanks, I am using a 10SI Delco Remy, I'll check the connections again.

Listen to Owen.. he gave you CORRECT advice.

(quoted from post at 22:58:14 06/21/14) Listen to Owen.. he gave you CORRECT advice.

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OK, thanks for all your help.

(quoted from post at 20:10:31 06/21/14)

(quoted from post at 19:25:37 06/21/14) The lack of a resistor will not cause the battery to discharge with the engine not running. It will prevent the engine from stopping when the switch is turned off.

Assuming you are using a 10SI Delco Remy alternator, check to make sure you have the wire from the battery stud on the alternator connected to #2 terminal and the wire from the ignition switch, through a resistor or diode, connected to #1 terminal. If #1 terminal on the alternator stays hot when the engine is not running it will drain the battery.

Click to expand...

Ok, thanks, I am using a 10SI Delco Remy, I'll check the connections again.

Click to expand...

Another question, if I install an internally resisted 12V coil, can I eliminate the resistor or diode?

are u saying I did not?

(quoted from post at 23:08:10 06/21/14)

Another question, if I install an internally resisted 12V coil, can I eliminate the resistor or diode?

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You can eliminate the resistor for the ignition system by using a 12 volt coil but you will still need some way of keeping the #1 terminal of the alternator from back feeding the ignition circuit and preventing the engine from shutting down when the switch is turned off.

This can be done with a diode which stops any current from coming back out of the alternator to the ignition circuit, a resistor which drops the voltage of the back feed too low for the engine to stay running, a light bulb which can serve as a charge indicator and also lowers the voltage, an ignition switch with separate accessory and ignition feed terminals, or a separate source to energize the #1 terminal. A separate source could be a switch that you manually activate to provide the power or it could be done automatically by using a switch closed by engine oil pressure.

Thanks Owen, and everyone for your help. I can get it going with this information.