Alt Wires On A 79

[79dog]

Hello again, coming off the alt is a 3 plug connection. That plugs into a connection coming off the harness around the voltage reg. That connection has broke on my car. All I see are two wires. I figure the black goes in the top center hole but I can't figure which side the other wire goes. And was there a 3rd wire somewhere? Any pics or info is welcome. Thx...

 

[jrichker]

See if this helps....

 

[79dog]

I'm just using a stock 79 alt. I have a sta, fld bat and grd. Which has me wondering, theres nothing hooked to the ground.

 

[jrichker]

I'm just using a stock 79 alt. I have a sta, fld bat and grd. Which has me wondering, theres nothing hooked to the ground.

Alternator ground is usually through the alternator frame. Be sure that the engine to body ground on the back of the intake manifold to the body is in good condition.

 

[RsStanG1987]

I have the alt from my 83 I can look at..


Yellow Bear racing 2k13

 

[79dog]

ok, tomorrow I'm hooking up all the grounds and see what happens.

 

[79dog]

Well, here's an update. The Alt bracket on my 79 is not steel. At least a magnet don't stick to it. So, I guess I need to run to the parts store and get some connections to hook the Alt ground up.

 

[jrichker]

If it is aluminum, that's better that steel. They use aluminum wire for mains in most houses nowdays.
I have never seen a plastic alternator mount on any Mustang, so an extra ground wire shouldn't be needed.

 

[79dog]

update, did you know it helps to have the dash cluster hooked up?

 

[jrichker]

The 87-93 Mustangs have a 500 ohm resistor in parallel with the Alt warning light. It connects with the Green wire on the alternator. It serves to tell the voltage regulator to turn on when the ignition switch is in the Run position. Your car may have a similar arrangement.