Recently my 2000 Chevy Blazer has not been producing any heat. If I put the heat on the lowest setting, it eventually gets mildly warm, but nothing hot enough to keep me warm.

I checked the fluid level and it's great. The line into the heater core is nice and warm, but the line coming out of the heater core is cold. Could this mean I have an air bubble in the heater core?

Also, I understand that this could be symptoms of a faulty thermostat. Let me know what you think. ]

Thanks

Does engine get up to normal operating temp? If it does this sounds like there isn't enough coolant being sent thru heater core - either restricted, plugged up and flushing it would show that,

T
Tom Greenleaf - MetroWest Boston - USA
_________________________________________

http://www.autoacsystems.com/tomgreenleaf/

It gets up to around 180 degrees, which I thought was a normal operating temperature. How would I flush the heater core?

Gauge may be wrong. It really ought to read 220F or so and stay steady there. Edit: should read close to thermostat temp - typically 195F or so. Vehicle's gauges are approximate.

You may have a thermostat problem. From cold, feel upper rad hose. It should stay cold till thermostat starts to open which takes several minutes. If you notice it warm up fairly quickly the thermostat isn't shutting well and that would throw this off. Be careful please but upper hose should be too hot to hold.

To flush a core only you would remove the two hoses and rig up water to flush back and forth thru it with like garden hose but you can't use full pressure. If it really needs this it's best to do the whole cooling system and start off with new anti-freeze.

This is a good job to farm out as it makes a real mess and this time of year many folks have put hoses away. Know that anti-freeze is toxic and kills plants and shouldn't be left around open at all as animals and perhaps a child would drink it and that's NOT GOOD! It's a hazmat and should be treated as such.

Again this is probably just a thermostat and I suggest paying for an OE one,

T
Tom Greenleaf - MetroWest Boston - USA
_________________________________________

http://www.autoacsystems.com/tomgreenleaf/


(This post was edited by Tom Greenleaf on Dec 21, 2007, 8:49 PM)