electrical issues--charging system 02

[94&92Astro]

My 02 Safari voltometer always read 13-14 and now 10-11.. It seemed to suck my battery down to the point where sometimes it won't even start, but it will keep the van running until I get to a stop and then I have to keep pressure on the gas peddle so it won't die...
I got a rebuilt Alternator from Autozone after they tested the old one (bad) and I went down to Wal-mart and swap out for a new battery...and although everything seems fine I still notice my alt guage reading 10-11 and as my luck would have it after a couple days of driving out of action once again..After reading several post here to gain some hindsight into the problem I started checking ground wires anywhere I could find one--I then noticed one of the large connectors on the solonoid atop the starter had some plastic missing and as soon as I pulled the starter down to get a better view, the plastic around this connector just crumbled out of the body and the only wire I had to disconnect was the small one to get the starter out--After this long winded explanation My questions are: Would the loose damaged connector contribute to the above mentioned charging condition and what would cause this connector to crumble before my eyes? (heat, age, wiring issues???)

[old_master]

The positive battery cable, (4ga black wire), runs from the battery to the starter solenoid. There is a second wire, (10ga red wire), attached to the same connection at the solenoid. That second wire, (has a fusible link in it), runs up to the back of the alternator. If the connection between the two wires on the solenoid is poor, or the fusible link is burned out, the alternator can not charge the battery.

Autozone alternator testers and alternators... don't trust them.

Disconnect the brown wire from the top of the alternator. Turn the ignition switch to the RUN position, engine off: You must have battery voltage on the brown wire, battery voltage on the red wire on the back of the alternator, and the battery indicator light on the dash must be on. If all that checks OK, and it does not charge, you have a faulty alternator.