Engine running hot
 

I've got a 1998 Blazer, it started running hot today. It got up around 240 before I noticed it and pulled into AutoZone. I've got plenty of coolant, no leaks. So I went in and bought a new thermostat, replaced it and it's still running hot,..so I pulled it out and I'm now running with no thermostat, and it's still running hot. I can run the heater and get it to drop to about 180 or so. Any clues to what would be causing this problem?? I appreciate any help in advance!
:icon_doh:

You have plenty of coolant, but overheating. Coolant may not be moving. If thats the case, water pumps make the coolant move. That would be the first place I would look, followed next by a clogged radiator. How many miles on your 98?

It's got about 130,000. I noticed last night after I posted this that the coolant didn't seem to be circulating. Water pump would make sense,...guess i'll give that a go.