spiking engine temp, dropping voltage?

[chrisl757]

Driving to work today and my engine temp cycled back and forth from 210 all the way up to the red band (but never into the red).

Then a few miles later, it sounded like the belt was squeaking, and my voltage dropped down to 9 volts.

And then the belt stopped squealing, voltage went back to 12 volts, but I still had the engine problem.

What is this?

At first I thought it was a bad thermostat, but now the belt noise makes me wonder if it's something else.

any ideas?

[chrisl757]

which seized, ripped up a belt, and messed up my day.

since the jeep is too far from home, now I get to pay somebody to fix it....wonderful.