sparks fly and i dont want to fry anything

[stock1970]

my stock 70 302 bronco failed to start a month ago, it just clicked once as if battery was totally dead, i disconnected the pos and neg cables to battery and reconnected and it started.. then just last week it did it again, i figured the switch was going out so i changed it and the battery cables. i am pretty sure i connected everthing back up to switch correctly but now when i try to connect the battery cables back up it sparks so hard it leaves a spark mark on the battery post.. .. maybe i connected something up wrong from the alternator to the switch and ground i am not sure.. there are two black wires coming out of the atlernator harness of wires along with the others.. are they both ground or what.. all help would be great..

 

[surfer-b]

yeah, you have grounded a pos. somewhere, check out this post for the alt. wiring how-to, its just one of the many:
http://classicbroncos.com/forums/showthread.php?t=131718&highlight=alternator+field+stator+wire

 

[Viperwolf1]

The large black wire goes to the BATT terminal.

 

[zeeman1]

Sounds like you grounded a + wire, easy fix, but finding it can be fun.

 

[stock1970]

i figured it out.. i took all the old electrical tape off of the wiring on back of alternator and it turns out the two black wires i was worried about were one wire. someone had taped up with the rest.. this wire went from the ground on the block to the fender bold that the switch uses.. i removed that and hooked it all back up and held the neg cable on the battery and the bronco was trying to start.. i put the old switch back on and everything is good it turns out the new switch i purchased was stuck to the on position.. who would have thought that the new part was the bad part.. lol..

 

[zeeman1]

glad you got it, thats always a great start for the weekend!