79 alternator/charging system question
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79 alternator/charging system question
I have a 1979 302 carbed that im putting in my 86' bronco 2 its in runs great and everything but the batt isnt being charged back up. I have everything hooked up except for the plugs they are flat one has 2 wires the other has three can anyone tell me what the wires in these plugs do?? and maybe which ones need what so i can splice them in to charge the batterey thanks guys
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im honestly not sure its turned into such a mess its a donor alternator all i know is the 3 wires that come off one goes to the batt post on the and the other 2 go into the voltage regulater i think and out of the voltage reg comes 2 plugs one with three wires and the other with 2 and some of the wires are hott some arent i imagine these need to go somewhere but im not sure where or what they do the 86 bronco 2 had efi and some weird stuff so im just trying to splicve what i need and all that sorry if i didnt answer the question is there a specific way to figure this out or can imake my own wire harness??? thanks man.
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Look close at the regulator on the Bronco. See if you can find the terminals labeled "I", "A", "S", and "F". They may be embossed in the plastic.
If you have that, then you should have a red/lightgreen on the "I" already. The "A" should have a yellow on it already. All you have to do is make sure;
the orange/lightblue wire goes from the "F" of the regulator to the "F" of the alternator,
the white/black "S" of the regulator goes to the "S" of the alternator(This may also go to the choke on the carb)
And a large black/orange goes from the bolt on stud of the alternator to the battery +. This usually hooks to a splice in the harness and then to the +bat side of the starter solenoid.
If you have that, then you should have a red/lightgreen on the "I" already. The "A" should have a yellow on it already. All you have to do is make sure;
the orange/lightblue wire goes from the "F" of the regulator to the "F" of the alternator,
the white/black "S" of the regulator goes to the "S" of the alternator(This may also go to the choke on the carb)
And a large black/orange goes from the bolt on stud of the alternator to the battery +. This usually hooks to a splice in the harness and then to the +bat side of the starter solenoid.
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Look close at the regulator on the Bronco. See if you can find the terminals labeled "I", "A", "S", and "F". They may be embossed in the plastic.
If you have that, then you should have a red/lightgreen on the "I" already. The "A" should have a yellow on it already. All you have to do is make sure;
the orange/lightblue wire goes from the "F" of the regulator to the "F" of the alternator,
the white/black "S" of the regulator goes to the "S" of the alternator(This may also go to the choke on the carb)
And a large black/orange goes from the bolt on stud of the alternator to the battery +. This usually hooks to a splice in the harness and then to the +bat side of the starter solenoid.
If you have that, then you should have a red/lightgreen on the "I" already. The "A" should have a yellow on it already. All you have to do is make sure;
the orange/lightblue wire goes from the "F" of the regulator to the "F" of the alternator,
the white/black "S" of the regulator goes to the "S" of the alternator(This may also go to the choke on the carb)
And a large black/orange goes from the bolt on stud of the alternator to the battery +. This usually hooks to a splice in the harness and then to the +bat side of the starter solenoid.
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From: Virginia
If it still won't charge;
With the truck off, check for voltage at the large terminal on the back of the alternator. If you do not have voltage there, then there is a fusible link blown in this wire.
If you have voltage, then take the "F" wire off the back of the alternator and tape it so it won't short out. Then get a scrap piece of wire and hook it to the "F" of the alternator, and lay it up beside the battery. Get the engine started, and put a meter on the battery. Then touch the scrap "F" wire to the battery +. If the voltage jumps up on the battery, and the engine slows a little and the alternator may even whine a little bit, that means the alternator is good.
With the truck off, check for voltage at the large terminal on the back of the alternator. If you do not have voltage there, then there is a fusible link blown in this wire.
If you have voltage, then take the "F" wire off the back of the alternator and tape it so it won't short out. Then get a scrap piece of wire and hook it to the "F" of the alternator, and lay it up beside the battery. Get the engine started, and put a meter on the battery. Then touch the scrap "F" wire to the battery +. If the voltage jumps up on the battery, and the engine slows a little and the alternator may even whine a little bit, that means the alternator is good.
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If it still won't charge;
With the truck off, check for voltage at the large terminal on the back of the alternator. If you do not have voltage there, then there is a fusible link blown in this wire.
If you have voltage, then take the "F" wire off the back of the alternator and tape it so it won't short out. Then get a scrap piece of wire and hook it to the "F" of the alternator, and lay it up beside the battery. Get the engine started, and put a meter on the battery. Then touch the scrap "F" wire to the battery +. If the voltage jumps up on the battery, and the engine slows a little and the alternator may even whine a little bit, that means the alternator is good.
With the truck off, check for voltage at the large terminal on the back of the alternator. If you do not have voltage there, then there is a fusible link blown in this wire.
If you have voltage, then take the "F" wire off the back of the alternator and tape it so it won't short out. Then get a scrap piece of wire and hook it to the "F" of the alternator, and lay it up beside the battery. Get the engine started, and put a meter on the battery. Then touch the scrap "F" wire to the battery +. If the voltage jumps up on the battery, and the engine slows a little and the alternator may even whine a little bit, that means the alternator is good.
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what test?? testing the alternator? i figured it was working cause the meter moved when i revved the truck but with the meter not moving as much as it should and returning to a low level of about 11 at an idle thats what lead me to guess voltage regulator
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From: Virginia
These two tests from a previous post. These will tell us if the alternator is good, and the fusible link is not blown.
If it still won't charge;
With the truck off, check for voltage at the large terminal on the back of the alternator. If you do not have voltage there, then there is a fusible link blown in this wire.
If you have voltage, then take the "F" wire off the back of the alternator and tape it so it won't short out. Then get a scrap piece of wire and hook it to the "F" of the alternator, and lay it up beside the battery. Get the engine started, and put a meter on the battery. Then touch the scrap "F" wire to the battery +. If the voltage jumps up on the battery, and the engine slows a little and the alternator may even whine a little bit, that means the alternator is good.
If it still won't charge;
With the truck off, check for voltage at the large terminal on the back of the alternator. If you do not have voltage there, then there is a fusible link blown in this wire.
If you have voltage, then take the "F" wire off the back of the alternator and tape it so it won't short out. Then get a scrap piece of wire and hook it to the "F" of the alternator, and lay it up beside the battery. Get the engine started, and put a meter on the battery. Then touch the scrap "F" wire to the battery +. If the voltage jumps up on the battery, and the engine slows a little and the alternator may even whine a little bit, that means the alternator is good.
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ok yeah sorry i checked the fusable link on accident i touchd the wire to the block unplugging it and it sparked so im sure its good. i changed the voltage regulator and still not charging so im taking the alternator in tomorrow to autozone they'll test it for free so if thats not the problem then i have no idea whats going on but hopefully ill find it there and change it out.
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