> The needle on the temp. gauge never seems to go above the top edge of
> the warning light.  At that point it triggers the high speed cooling
> fan.

The high speed fan should not be triggered until the needle gets near the
top of the guage.

I can think of three possibilities:

1) The temp guage is wrong and the van really is overheating. (the sensor
for the guage has nothing to do with turning on the fan.  The fan has it's
own switch installed in the radiator)

2) Someone modified the fan wiring to turn on the high speed instead of
low when the temperature starts to rise.

3) The fan switch is defective, turning on the high speed at too low a
temperature.

Bill