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Hey yall I have a 86 F150 with the 5.0 got rid of the efi and went to a carb. ( having problems with the system.) plus I like carbs better. But anyway I cooked the battery and tested the volts I was running at and it was 18.5 so i replaced the voltage regulator alt and battery which all could have been needed anyway but I am still running 18.5 or so. I have not driven it a good distance yet cause I am not sure if I will cook the battery again or not. Is That normal for it to be running that high? Thanks for the help yall. Just want to check myself before i cook another battery
18.5 is too high. If you run it long you will cook the battery again. Check the yellow "A" wire going to the regulator and make sure you have 12v on this wire with the truck off.
Thanks for the input. I will check when I get home from the station. Also it has the a-s-f-i voltage regulator and there is nothing connected to the i. Which i was told was not a problem because that is just the gauge in the truck. Is that correct?
Here's how it's wired. Not having the "I" connected means you have the gauge package in the dash, that's normal.
The A terminal is what the regulator uses to determine how much the alternator should be charging.
When the regulator determines how much the alternator should be charging, it puts this variable voltage on the F wire and the variable voltage on the F is what controls the alternator output. The S wire on the regulator brings the system online when the keyswitch is in run. The S wire on the alternator is optional if you have a factory choke.
Hey thank you for the diagram. I will go through and make sure its all correct. Right now So I am thinking the guy at ricart ford here in columbus told me wrong cause he had me attach the s on the alt to the s on the regulator. That is probably why the regulator is not coming on and registering the info. So I am going to need to attach that to a key hot wire?
Your wiring should have a green/red in the harness near the regulator. That should have voltage when the key is turned to run, and that is what hooks to the S terminal of the regulator.
The only time the S terminal of the alt is hooked to the S terminal of the regulator is in the different configuration that uses the I terminal and a idiot light in the dash.