Bleeding heater core

[grindkings]

I just got done replace the heater core in my 91 blazer, fun job. However, i think i needs to be bled because it acts like there is a large air pocket in it. WHen i went to fill up will colant ony about 2 gallons went into the whole system. How can i bleed the heater core?

 

[Muddytazz]

Get your motor to operating temp so the t-stat is open and your coolant is flowing throughout the complete system, then add my coolant.

 

[kevcarr59]

Coolant Level..

When it's cold go ahead and start it but leave the radiator cap off. When it reaches temp the thermostat will open and the water will circulate. Leaving the cap off will release any pressure in the system, making it easier to get the air out. Go ahead and fill to bottom of rad. neck after it had run a few minutes.

 

[grindkings]

I went ahead and filled my radiator but my air or heat dosn't work AT ALL!

 

[Grim-Reaper]

I went ahead and filled my radiator but my air or heat dosn't work AT ALL!

Bet you hooked the lines up backwards. the bottm line is in from the instake and the top line is out to either the radiator or the water pump.

Also some people make the mistake of putting one line to radiator and one ot the water pump. Those are both returns and it will not circulate.

Also make sure the flap is opening. The control for heat is the flap on top of the box that you can see with the Glovebox out.