359 tach signal wire

The alternator only has 2 wires. A positive and the ground. I’ve never seen a smaller wire attached any where on the alternator or more than the 2 from factory. I agree with the idea that it was working till the alternator was done. So you have to start with what they were fiddling with. Unless some ####### ran a separate power wire to the tachometer due to a bad connection etc at some point in the trucks life. I think that be a rare event personally. If I’m not mistaken that twisted pair off the tach and speedo come around the right rear of engine. Then through the fire wall on right side. I’m sure the Speedo does the tach I could be wrong. One possibility is all the kysor engine protection is right there in amongst that alternator at the center of head. If he grounded some of that out and it tripped a breaker on the switched accessory circuit that gets yiur tach and temp guage. The temp could be a liar in this scenario and stay in the middle. One of the switched accessory circuits will kill the fan too, the speedo should be with the tach as far as switched power. But at that trucks age anything is possible. Many will just piggy back power from another circuit. I would start looking in that loom that has the Jake’s and the kysor stuff. I’m betting that was tugged on during removal and partially unplugged tach or there is a wire grounded out in the twisted pair

 

Where have you been?

 

I would definitely loosen the ground cable and rotate it down like the other one to take the stress out of the crimp. Wouldn't hurt to put another end on with a proper crimp and some heat shrink?

 

Glad they could be of help. I would hate to have to start the New Year off by having to fire these guys.

 

You still selling that subpar Canadian hay to unsuspecting Amish folks?