Heat won't shut off

[Cordoba Tom]

The heater control on my 1982 Cordoba didn't work at all, except the heat was always on. I bought another unit, and all the buttons work, and the fan works good, but the heat still doesn't shut of no matter what adjustments I try. Has anyone had this issue, or know what may be going on? Maybe the solenoid on the heater core hose under the hood? Thanks! Tom

 

[Mikes5thAve]

If it's not the controls or the vacuum lines going to the controls it could be a stuck blend door causing it. On 5th avenues it's electric. I don't know if it is or not on the other cars.

Even with the valve under the hood open the heater box should still stop the heat. The valve is usually out of the picture on both of mine and never had it cause issues with heat.

 

[Cordoba Tom]

I'll double check the vac lines. I have them connected okay, but could they be disconnected somewhere? I'm guessing the blend box is under the heater core? Thanks!

 

[FredMcJoe]

Read thru these very helpful messages regarding "blend door".
Search results for query: blend door

Your 1982 Cordoba is equipped with the "semi-automatic air conditioning" system. Really, the only thing automatic about these is that the blend door has an electric motor which opens or closes the blend door based on the temp setting the lever is put too. It's a given that the blend door motor will go out on these cars, I have a dead one in one of my cars right now. I don't know of a replacement motor but there is mention that the electric plug gets loose so you may not need the whole motor.
Search results for query: blend door

 

[Cordoba Tom]

Thanks for the info. Certainly the connection is an easy place to start, and I'll let you know!
Tom

 

[FredMcJoe]

I think it's accessed after removing the glove box if I'm remembering it right. Finding a model with the standard A/C with the manual cable for the temp setting and removing the servo motor, and replacing the control unit with the manual style is one way to put a fast fix for it. There's quite a few of these manual cables available online, you'd also need the control unit holder, the semi auto type has an electric slide switch whereas the manual has a pivoting lever.
nos heater control cable 1976 aspen volare at DuckDuckGo

 

[Cordoba Tom]

I will be back in town next weekend and will try to access the blend door then, and I appreciate the closing ideas for opening and closing it.
Tom

 

[Cordoba Tom]

I think it's accessed after removing the glove box if I'm remembering it right. Finding a model with the standard A/C with the manual cable for the temp setting and removing the servo motor, and replacing the control unit with the manual style is one way to put a fast fix for it. There's quite a few of these manual cables available online, you'd also need the control unit holder, the semi auto type has an electric slide switch whereas the manual has a pivoting lever.
nos heater control cable 1976 aspen volare at DuckDuckGo

I did remove the glove box and found the blend door. I wired it closed to make sure that took care of the problem, but the heat is still coming through. Could there be another door that is in that area, and I closed the wrong one? I also closed the valve in the hose to the heater core and that didn't do anything either. Any thoughts? Thanks, Tom

 

[Justwondering]

Cordoba Tom ...
Just to be sure, is there any smell of engine coolant or exhaust in the heat coming out the vent?

You've checked to see the the prior owner already installed a manual line/switch/lever to control the blend door? I ask because we did that with an old truck and when mom drove it going to town for sandwiches, she came back sweating and cursing the heat in the truck. Didn't know about the override for the broken blend door.

My initial smarta$$ remark would be 'move somewhere it stays cold all the time' but given the erratic weather this year, I'm not sure even that would be possible.

I do have 1987 Fifth Avenue service manual if any of the pictures would be helpful. Not sure of the overlap with your vehicle.

Let me know,
JW

 

[AMC Diplomat]

The heat is still blowing through?

Disconnect the blower motor

 

[Cordoba Tom]

Cordoba Tom ...
Just to be sure, is there any smell of engine coolant or exhaust in the heat coming out the vent?

You've checked to see the the prior owner already installed a manual line/switch/lever to control the blend door? I ask because we did that with an old truck and when mom drove it going to town for sandwiches, she came back sweating and cursing the heat in the truck. Didn't know about the override for the broken blend door.

My initial smarta$$ remark would be 'move somewhere it stays cold all the time' but given the erratic weather this year, I'm not sure even that would be possible.

I do have 1987 Fifth Avenue service manual if any of the pictures would be helpful. Not sure of the overlap with your vehicle.

Let me know,
JW

I am sending a few pics showing that I closed the valve on the heater core hose, and that I do have a clothes hanger hooked up to open and close the door. Like I say, even with the door closed, the heat comes through. Thanks for hanging in there with me on this.

 

[AMC Diplomat]

Is this an AC car? Is the "heat" just worthless AC? Did you try unhooking the blower motor?

 

[Cordoba Tom]

Is this an AC car? Is the "heat" just worthless AC? Did you try unhooking the blower motor?

No I haven’t. I’ll give it a try. One other member mentioned that also. Thanks.

 

[FredMcJoe]

No I haven’t. I’ll give it a try. One other member mentioned that also. Thanks.

if you're in WI, you'll soon need the heat. I have an idea that if you remove the electric servo motor from the top of the heater housing, the blend door will rest in a default position of supplying heat. Instead of replacing the servo if you can find one, and if you don't want to mount a cable unit from an older Volare/Aspen, you could devise a means of connecting a bent rod that could be fashioned to hang outward and then down from the blend door shaft so you can manually adjust the heat. You'd have to design a way to hold it in position too, probably.

 

[FredMcJoe]

I am sending a few pics showing that I closed the valve on the heater core hose, and that I do have a clothes hanger hooked up to open and close the door. Like I say, even with the door closed, the heat comes through. Thanks for hanging in there with me on this.View attachment 50810View attachment 50810View attachment 50811View attachment 50812

I could be wrong but I think the foam padded door is for air recirculation for when the unit is in Max Cool. So if your interior is warm, that will only keep the cooler outside air from coming in if it's open to the interior. The blend door problem is over on the other side of the heater box near the center of the firewall. It's a servo motor that sits ontop of the housing. Remove the motor and ponder how it moves the blend door then start designing a manual rod. It's accessible thru the glove box once the box is removed, removing the passenger side lower cover below the glove box may make it easier to take out too.

 

[Cordoba Tom]

Yeah, I will need the heat soon, but still hitting around 80 the next few days. I actually tried connecting a coat hanger to the door after I disconnected the actuator behind the glove box, closed the door with it, and locked it in place, and it still let the hot air in. If it worked, I was going to connect the aspen cable. It wouldn't matter to me if it was manual or not, but it didn't stop the neat. Not sure what I am doin g wrong with it. Thanks for staying connected with me on this. I'm open to suggestions.

 

[Cordoba Tom]

I just saw your previous post, and yeah, maybe that wasn't the blend door I connected to. So the servo is inside the car, and I should be able to see it on the left after I remove the glove box?

 

[FredMcJoe]

I just saw your previous post, and yeah, maybe that wasn't the blend door I connected to. So the servo is inside the car, and I should be able to see it on the left after I remove the glove box?

yep, it's tucked down in there but it looks like it was just barely designed to be accessed down in there. Check the electrical connector first, they can get loose I have heard

 

[FredMcJoe]

allpar.com/threads/blend-door-servo-wanted-89-5th-ave.240650/

See part #9? that post on the back of it pokes up thru part #2, and the servo will be ontop of it

 

[Cordoba Tom]

Wow, thanks for the diagram. Nope, I didn't have the blend door connected to the coat hanger. I will take a look at the location above number 2, and let you know how I make out. Thanks again!