I've had my temp go up to about 190*-195*, soon as I hit the the highway, it dropped back to 160*, bled the system 2-3 times by lifting the passenger side, cap off,ect. Temp shot right up, now I'm back in the same ballgame @ 160* all the time, new stat, cap, ect... But I did notice in the rad which is extremly clean, I never get any flow up top when hot, from the fins wondering could this be the problem? But the rad looks new! Any ideas please chime in, need to put this problem to bed quickly. When I race the engine, cap off the a/f drops down 3-4 inches,let off, comes back with some spillage, but never see any flow out of those upper fins!!!!!!!! Don't seem right ?

 

A new thread?

If there is no air in the system, you have to have something that is allowing coolant to bypass the thermostat.

 

bypass hose

 

Get rid of the bypass hose and let the thermostat do its job. Your temp should get to normal then.

 

That bypass hose is there for a reason.

 

is your water pump working?

190 is typically the thermostat recommended for your truck. It should get to 190 before opening, and it will drop down due to the cooler fluid mixing, it should rise back up to normal temp and however around 190 all the time.

 

The pump gotta be working?, or it would overheat. When i jacked it on the passenger side to bleed it afew times the temp went to 190*-195*, but when I hit the highway, bang right back steady @ about 160* after that thats where it stays all the time... Today bleeding again, I did notice a no flow condition on the top fins in the radiator and it super clean in there as well as the a/f.

 

My wife took the Blazer to work last night, and says she hears gurgling in the dash area, could this be air in the heater core? if so what do I supposted to do to get it out? I'M AT WIT"S END WITH THIS PROBLEM !! Can the water pump impeller be broken off w/o knowing even though it don't overheat?

 

PROBLEM IS SOLVED ! Today I put the truck up on ramps for about 3-4hrs bounced the front bumper quite a few times and let it sit. Then I started her up with the cap off right away you could see from the upper fins bubbling of air coming out the stat opened @ 190-195 the level dropped abit, topped it off, put the cap back on, took it off the ramps, went for a ride, the temp stayed like rock @ 190-195.

 

PHEW!! I was beginning to think I did not know what I was talking about anymore.