So I get around to taking a good look at my alternator on my 78 F-250 4X4 with a 351M in it.
And I notice that it isn't the right one. It doesn't reach the tension band for the second bolt. And only has one place for a wire on the back. There are 3 wires coming out of the wiring harness that goes to it, and they look like they should go to the alternator. Can that thing work well in that condition??? The wires are what really throw me. The one wire that is hooked up goes to the positive terminal of the starter relay. Can that charge adequately??? Had some battery dead problems lately causing me to wonder?
The belt worked itself loose because there is only one bolt holding the alternator on and checking that out I found the rest.
Any help would be greatly appreciated!!!!!!

 

>It doesn't reach the
>tension band for the second bolt.
>And only has one place for
>a wire on the back.
>There are 3 wires coming out
>of the wiring harness that goes
>to it, and they look like
>they should go to the alternator.

There can be 2 or 3 wires to the stock alternator. You definitely need an orange wire to the field and a black/red striped wire to the starter relay. The white/black stripe wire to the stator terminal is kind of optional depending on the model of truck. Usually it supplies voltage to the electric choke.


> Can that thing work well
>in that condition??? The wires
>are what really throw me.
>The one wire that is hooked
>up goes to the positive terminal
>of the starter relay. Can
>that charge adequately???

If it is the stock alternator I would say no.

>Had some battery dead problems lately causing
>me to wonder? The belt worked
>itself loose because there is only
>one bolt holding the alternator on
>and checking that out I found
>the rest.

By the decription I would say it is the wrong alternator for the truck. Maybe someone added another type of alternator say from a Dodge or Chevy.
If you dont think it is a good setup. Pick up a stock alternator and get a wiring diagram to help. Actually reply with what type of voltage regulator you have and the number and color of wires on it. Then I will give you more help returning it to the stock Ford setup if you want.
Good luck and hope this helps.
Sparky

 

Mike alt aren't very expensive, I would suggest you go to a parts house and get a lifetime warranty reman. (correct) one, and use the one that you have as a core trade.

Good Luck


John

66 F100s
In the still cool hours of the night, you can hear chevys rusting away.