Mechanics

CHEVROLET BLAZER HEATER PROBLEM

1998 Chevrolet Blazer • 176,000 miles

I had heat in my blazer.I had pinhole on heatercore hose.I cut off the bad spot. Hooked hose backup lost heat.I replaced thermostat had radiator flushed still no heat
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Jnurse
March 7, 2013.



You probably have air trapped in the heater core. That's why we usually use vacuum to fill the cooling system.

Wrenchtech
Mar 7, 2013.
How do I get the airpocket out

Tiny
Jnurse
Mar 7, 2013.
It should work out on it's own.
With the engine at full operating temp, locate the 2 heater hoses where they go into the firewall and feel them to see if they are both hot to the touch.
If you find that they are both too hot to hold, then the heat in that vehicle is controlled by a blend door that regulates heated air flow. It is operated by an electric motor/actuator. The problem can be that the actuator is stripped or inoperative or the door itself could be damaged. This is what needs to be determined by examining the actuator and see if it is responding to heat change commands or not.
If they are both not too hot to hold on to, then you either have a restricted heater core or the system is not completely full and getting air pockets for some reason.

Wrenchtech
Mar 7, 2013.