Fan clutch and overheating?

[bowtie_pasta]

Ok, I had my first overheat experience with my Blazer yesterday.  Had to pull over and let her cool down.  Visual check reveals nothing.  Coolant level fine, no leaks from radiator or water pump.  Upper radiator hose is hot, so I don't think the Tstat is stuck.  No squealing noises, nothing.

 

So, I'm about to start small and work my way up.  The fan clutch doesn't seem to have any resistance when the engine is hot.  In fact I don't hear the 'roar' of the fan pulling hard RPM's like it used to when the engine started to temp a little.  I'm going to change it.  I hear they are only good for 100k anyways.

 

Have any of you folks ran into this problem?  I'm hoping it's not the water pump.

 

PS- the truck has ~95,000 on it.

 

Thanks peeps!   :thumb:

[bowtie_pasta]

Changed fan clutch - no dice.

 

Changed thermostat - bingo, cool as a cucumber!  Wheeeew, that's all I have to say!   :hail:

 

later