I have a 01 f350 7.3 . To start the battery light come on and the gauge went up to 18v on dash shut off and restarted same got it home about 2 miles . Started up next day battery light on gauge normal, noticed power steering pump seal went out and covered Alternator didn't test it . I got ahold of a new 200a powermax alternator , light still on , also it has 2 new deka 875cca battery's that might have 20 starts on them . I got 11.7 volts at both battery's hooked up and separated or disconnected ,same 11.7 on the big lug on alternator ,now if I take the big wire off alternator I 14.5 volts on the alt. lug. ( does this mean its working properly?) . If I unplug the small wire on alt. the light goes out.

Also the new alt. plug is different the alt has 3 prong and a separate one prong the 3 prong is marked A S I need to know if green goes to I and orange to A.
Any help very appreciated.

 

Moved from intro forum to tech forum.

Welcome to FTE!

 

Here are the charging diagrams. I hope they help.

 

Thank you that answered my wire location.

 

Anyone know if the 14.5 volt out of the disconnected alt is sign of a good alt?

 

When you say disconnected alt. You mean the wires are not connected to the plug and it still charges.

 

13.7 Volts with everything hooked up properly and working. With the batteries disconnected (big wire), the voltage doesn't matter because alternators work with a load attached... but can suffer damage when no load is present. 11.7 volts means you're operating on your battery charge alone. You need battery voltage to the "I" on the regulator to get the alternator to charge. If it's not there, you could have a bad fuse on that line.

 

Thanks for reply. This new alt must not be putting out . When all connected and I has battery voltage 11.7 I'm still only getting 11.7 v at battery stud on alt. I'll double check this info later in messing with this I herd the starter could stick and cause the bat light to come on so as I checked the starter I noticed one of the long bolts holding the motor together was broke off so got to take care of that first and then back to the charging issue .

 

Yes the battery wire on the alt disconnected , I get 14.5v out of the alt stud.i wanted to know if that means the alt was working properly.

 

With engine off I have 11.7 on pin A , with engine off key on I have 11.7 at pin A and I. Fusses must be good. Still no starter waiting for wife to get home with car. So when I get this running and both pins A I have voltage and I'm only getting 11.7 at alt battery lug does this mean alt is bad?