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03 astro. bleeding heater core.

1K views 4 replies 4 participants last post by  a7tl46 
#1 ·
Well I checked all the elements that might cause this no heat issue. Radiator is full. changed themostat. checked control valve with vacuum and operated correctly. Appears I'm not getting circulation in and out of the heater core. Have a 4 hose control valve, and the other 2 hoses get plenty hot. I just think the hot coolant takes the easy path through the valve and just recirculates back to the engine and never gets up the core hoses. Have run for close to an hour with nothing. Any sure way to get the air out of the core ? BTW.... also flushed the heater core and was quite clear
 
#3 ·
The water pump needs RPM's to push the water around to the heater core(s). Once you have burped it in the driveway, take it for a drive. One way or another, heat will work it's way around.
 
#5 ·
thanks for all replies. have done the drive thing. guess maybe a flush. i did bring up to temp and pulled the return hose from the heater core. Coolant flowed but at a trickle, and not really hot. Certainly not as hot as the other hoses. brick scan tool was reading 87-88 degrees from the thermostat. Think that should be higher.
 
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