> I took my van out to go camping this weekend.  About an hour and a
> half into the drive, it overheated.

I'm not a mechanic, but I've had my share of coolant problems.  Some
questions:

1)  was the (front) radiator HOT when it over-heated??
2)  Did the cooling fan come on when it over-heated??
3) did your temp gauge needle (on the instrument panel) peg to hot??

If the answer to these questions is NO, then I'd be led to question the
veracity of the water (coolant) pump,  OR some blockage in the lines
to and from the radiator or the the radiator itself.

Of course, air in the coolant system is to be suspected too, even an
air locked water pump.  But if you're happy that the system was
"properly" bleed then that's that.

Try letting the van idle for a long period of time and feel the hoses get
hot and how far forward the heat gets before the van over-heats, does
the fan come 'on', does the gauge peg to hot.

Thermostat failed CLOSED? (I don't think they do this do they??)
They fail open????

If the answer to the above 3 questions is YES, then ........... You got
me, most likely air in the coolant system letting only a small bit of
coolant to the front rad.

Anyway that's m2cw.  Malcolm