Alternator wiring troubles

[all4rocks]

I searched old topics on here about which wire goes where on the alternator. (blue and green one) Peoples answers were that it doesn't matter, it works both ways. It doesn't on my car. When I hook up the green wire the car wont start. it cranks but wont start. Any ideas?

[BruteForce]

Does it start with no wires connected to the alternator?

[all4rocks]

If I pull the green and blue wires off the car starts fine but no charging.

[Chryco Psycho]

Weird , the green wire grounds the field thorugh the voltage reg & should not affect the ign at all . do youhave wires mixed up , green could be tach signal feed & could be grounding the coil

[BruteForce]

I suspect a short to ground either in the green wire or the alternator itself.

A list of things to try:

1. get out the wiring diagrams and see where the green wire is supposed to go. Trace it and verify correct hookup with no frayed wires, etc. On an old car you can't always trust the wire colors, as some previous owner might have used different wires.

2. google to see if there's a way to bench test the alternator.

3. the voltage regulator may also be faulty - an internal short.

[ShelbyDogg]

I suspect a short to ground either in the green wire or the alternator itself.

3. the voltage regulator may also be faulty - an internal short.

The green wire only goes to the outside terminal on the voltage regulator. If the green wire was shorted, it will full field your alternator and kill your battery but not cause it to die.

The blue wire comes right off of the ballast resistor and the ignition switch. It can kill you engine with a short but would smoke the wire, bulkhead terminal, ign switch, etc. Check it with a test light on and off the alternator. I suspect your alternator too.