Alternator or regulator?

The charging circuit on the 97 Aerostar finally failed completely. The current had been cycling when running and headlights were on, but was too intermittent to get it checked out. I drove it 1/2 hour today, no
problems starting or running. Parked. Then a couple of hours later went out to start it, engine turned over slowly and then slowed to a stop without starting. Tried again and the solenoid was chattering. Did not notice what the ammeter read before it went dead.
I then put charger on the battery. 2 hours later, it cranked right up. While idling,I saw that the ammeter indicated it was discharging about midway between far left (discharge) and mid-point.
I'm letting the battery charge over night so I don' t get stranded while running for parts.
Now what I need to know - how to isolate the problem to the alternator or the voltage regular. Also, if it's one or the other, how difficult is it to r/r myself?
Would you recommend having O'Reilly's check out the alternator or regulator?
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in message news:... The charging circuit on the 97 Aerostar finally failed completely. The current had been cycling when running and headlights were on, but was too intermittent to get it checked out. I drove it 1/2 hour today, no problems starting or running. Parked. Then a couple of hours later went out to start it, engine turned over slowly and then slowed to a stop without starting. Tried again and the solenoid was chattering. Did not notice what the ammeter read before it went dead.
I then put charger on the battery. 2 hours later, it cranked right up. While idling,I saw that the ammeter indicated it was discharging about midway between far left (discharge) and mid-point.
I'm letting the battery charge over night so I don' t get stranded while running for parts.
Now what I need to know - how to isolate the problem to the alternator or the voltage regular. Also, if it's one or the other, how difficult is it to r/r myself?
Would you recommend having O'Reilly's check out the alternator or regulator?
*** Or better yet, how can I isolate it? I remember taking a car to O'Reillys years ago for the same problem. They put the meter on it and said right away that the alternator was bad. I had the local shop change alternators, but then the old unit checked out good. The problem had actually been loose connections at the alternator.
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On Sat, 1 Oct 2016 22:22:29 -0700, "Snuffy \"Hub Cap\" McKinney"

Why not just take it to a local shop to begin with?
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On Sat, 1 Oct 2016 22:19:27 -0700, "Snuffy \"Hub Cap\" McKinney"

the integrated regulator. I changed the regulator on my old aerostar twice for that same problem - when I finally replaced the alternator the problem went away. he brushes were OK and the diodes tested OK, but the charge rate was still intermittent. Theoretically a regulator should have fixed the problem and I highly doubt I got 2 bad regulators from 2 different sources. I was fortunate to find a quality rebuilt alternator at the wreckers - had just been installed a few weeks before the van ended up totalled. - for less than the cost of another regulator.
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