Heater issues
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Race Director
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From: Lansing MI
The heater core could be blocked partially or completely. Chances are pretty good you could back flush it with a garden hose and clear it out. The temp door could also be stuck on cold. Corvettes sure have plenty of hvac control head problems.
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From: Lansing MI
Disconnect the heater hoses in the most convenient location and jam a garden hose in one of them; then turn the water on. After a minute or so then jamb the hose into the other one and run water through it the other way. That's what I would do. If your antifreeze is nice and clean then you better make double sure its not the temp door stuck on cold.
Le Mans Master
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From: Orlando FL
If you turn your key the ON position and in an area where it is real quiet, you can hear the blend door move. Set your temp control to 60. Waite 30 seconds and run to 90 and sit and listen for 30 seconds and you can hear it move. You can then run it to 60 and listen again. If you can hear a creaking, it's probably moving.
If you decide to flush the heater core, use reduced water pressure as not to damage the core. Just a gentle flow. One hose comes off from the surge tank and the other from the plastic fitting (in line connector).
Did the heat slowly get cooler? Or did it just go cold one day. I assume your engine temp is 180+.
If you decide to flush the heater core, use reduced water pressure as not to damage the core. Just a gentle flow. One hose comes off from the surge tank and the other from the plastic fitting (in line connector).
Did the heat slowly get cooler? Or did it just go cold one day. I assume your engine temp is 180+.
Last edited by pcolt94; Jan 6, 2016 at 10:25 AM.
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I bookmarked this thread.
Mostly for laughs....
Next time search..... https://www.corvetteforum.com/forums...rchid=52286456
Mostly for laughs....
Next time search..... https://www.corvetteforum.com/forums...rchid=52286456
Last edited by JrRifleCoach; Jan 5, 2016 at 09:59 PM.
Burning Brakes
Joined: Jan 2011
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From: Kingwood Texas
Have you checked the blend door to see if it moves?
https://www.corvetteforum.com/forums...procedure.html
https://www.corvetteforum.com/forums...procedure.html
Last edited by MRPVette; Jan 6, 2016 at 09:32 AM.
Le Mans Master
Joined: Jan 2006
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From: Orlando FL
Have you checked the blend door to see if it moves?
https://www.corvetteforum.com/forums...procedure.html
https://www.corvetteforum.com/forums...procedure.html
You can also pull the controller out of the top of the evaporator so you can see the blend door. You can run it from one end (60 & 90) to another and see if it is moving.
Burning Brakes
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From: Kingwood Texas
Melting Slicks
Joined: May 2013
Posts: 2,692
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From: Sacramento California
Maybe the heater core has been bypassed. This is fairly common since the cores are known to leak after so many years, even if the cooling system is maintained well.
Bypassing the core is certainly not a fix but it does keep coolant from leaking into the cabin... and keeps the heater from working.
Bypassing the core is certainly not a fix but it does keep coolant from leaking into the cabin... and keeps the heater from working.
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I bookmarked this thread.
Mostly for laughs....
Next time search..... https://www.corvetteforum.com/forums...rchid=52286456
Mostly for laughs....
Next time search..... https://www.corvetteforum.com/forums...rchid=52286456
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Instructor
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From: rochester ny
Couple more pics
Here is what the blend door looks like (top left):
This is what my actuator looked like once I took it out:
Once you can see into the heater box set the temp to 90 and you should be able to see the door open then set to 60 and you should be able to see the door close. After replacing the blend door actuator I have heat again.
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[QUOTE=mwm1993;1591267863]
Here is what the blend door looks like (top left):
This is what my actuator looked like once I took it out:
Once you can see into the heater box set the temp to 90 and you should be able to see the door open then set to 60 and you should be able to see the door close. After replacing the blend door actuator I have heat again.[/QU
Where is the door actuator motor located at? Mine is no closing
Here is what the blend door looks like (top left):
This is what my actuator looked like once I took it out:
Once you can see into the heater box set the temp to 90 and you should be able to see the door open then set to 60 and you should be able to see the door close. After replacing the blend door actuator I have heat again.[/QU
Where is the door actuator motor located at? Mine is no closing
Le Mans Master
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From: Orlando FL
Where is the door actuator motor located at? Mine is no closing
One of the reasons the motors develop a problem is if the drain for the evaporator is clogged and back up, the water has nowhere to go and flows out into the cabin and right into the motor.
To get to the motor you need to remove the knee kick panel on the passenger side. Then underneath the motor hangs held on by 2, 7mm bolts and a connector.