I have a 2000 LT 4x4 4.3 Blazer, that has been running a little warm latey (Keep in mind I live in AZ) Last night the temp out side was around 102-104 range and my wife and I went up to chandler, Az for our grandson's 9th birthday. On the way up I notice the temp gauge going higher and higher until it hit 235, now it has never been this hot before and temp outside has hit 120 and up. It would run around 210-212 fan kick in with a whoose sound and the temp drop.

I have replace the radiator, both hoses, thermostat (sp) and today a new 16lb radiator cap.

It will sit in the drive way all day long running with the air on full blast and the temp won't even reach 210, but once I start down the road, it starts its climb.

I did notice that when I had the cap off and running, I didn't notice much circulation and the water was cool to the touch, but yet when I turn the heat on it was hot air blowing.

I'm thinking water pump even though its not leaking or doesn't appear to have any play, but it is orginal (97,300 mi).

I have also notice that the fan kicks in a little latter then it use to (around 210, now around 212-214 mark and doesn't make as much noise as it use to) I check the fan and when I try to twirl it with one finger, it might move a couple of inches, but then as I continue, it will have a spot where it might move 5 inches. Maybe the fan clutch is starting to go also?

I hear mention of the temp sensor, could that also be a problem?

Any ideas of how I should approach this? I tread the water pump and clutch fan change out, they are a real bear..and I refuse to pay someone 200 bucks to change the water pump....not including the part...but I'm getting older (on the back side of 61) and its gets a little harder and longer now days...

Thanks for any ideas.

 

Wow, I shouldn't mention taking it in to a shop and paying 200 bucks.

Thanks for all your answers, you all are great and a big help.