Won't stay started

I have 1994 Lumina APV 3.8. I replaced the altornator and the battery it will start but the battery gauge shows its charging at 10 volts. I have had both of htem checked to see if they both work and they do. I have no idea what else I can do to fix the problem. If anyone has had the same problem or knows whats wrong PLEASE help me

Do you have 12v at the alternator main post? (this is, engine not running).
I feel the connection from alternator to battery is lost and check fusible link H because it may have been shot if there was a short in the previous alternator.
http://www.avigex.ca/xport/fusiblelinkh.jpg

I'm not get a voltage from the wires on the altornator but the van will still start and run at 8 to 10 volts

YOU have no charging at all and you run on battery only. It will be dead in a matter of hours and will need a recharge. Keep a battery charger connected when you are home to keep it alive until repaired..

You have 2 hot wires at alternator:
www.avigex.ca/xport/charging.jpg
The heavy gauge RED wire should have 12V all the time so if it does not read any voltage check fusible link as said before or for a test run a separate heavy gauge wire direct from the heavy post on alternator to 12V main connector (with a red plastic cover) near the brake booster.

The smaller pimk-white wire at alternator should have 12V with key on only. Turn key to ON (engine does not have to run) and measure voltage.

Report results of these tests.

Thanks it worked had the change a few links but now its running great thanks for the info it was a big help thanks