I don't know if this has anything to do with it but they used to have a capacitor or some sort of condenser located next to the voltage regulator and if it was removed or missing then you would have the same problem or it wouldn't charge at all. they said it was to keep the alt. noise out of the radio but I have never heard it coming through the radio in my life. but when ever I had a vehicle and that thing was not there then I would have problems with the charging system

 

maybe not related, just saying, but i had the same problem on a 1996, found that both front power lock switches were shorted out, passenger side was totally charred, battery drain stopped as soon as i clipped that wire and replaced it.

 

Guess we will see. With a new alternator, the battery reads 13 and charging it reads 14.2.

 

Rusty, Does that E-150 have the old style alt. on it? The reason I ask is it does have that style is because there is a way to see if the charging system is working like it should and that way is if you can take the battery cable off of the battery positive or negative it doesn't matter which one just don't touch them to the other then if the engine still stays running then all of the charging is good. first you must start the engine before you take off the battery cable

 

If I put a voltmeter on the battery while trying to start it, how far down should the needle drop? I know it will rebound after I quit trying to turn it over. Just wondering how much juice a starter should draw?

 

If it goes below 9.6 volts, either the starter is pulling too much, or the battery is weak.
The starter in that engine should draw about 150 amps.

If you wanted to really get an accurate number, you could get one of those ammeters that you hold next to the battery cable (range 0 to 250 amps) and when cranking you can see the actual current draw.

 

Thanks, I will check it. I had the battery tested at Auto Zone and they say it is good, but who knows, I have had parts stores tell me that about stuff before and be wrong.

 

It drops to about 10 when cranking. And it will idle with the negative cable off as one of the other posters asked.
I drove it last night, just for a couple miles with the lights on. When I got back home and shut it off, I restarted it, but it turned over really slow. This morning I checked battery voltage (I unhooked the battery over night) and the battery showed 12.6, and it started without any problem. I left the battery connected this time. Guess I will see what happens now.

 

Rusty what do the battery cables look like ? Sounds like there could be some internal corrosion.

 

The ground cable is new. The positive is clean and has good connections.