Heater control cable

[Bonnewagon]

I got my AC working on the Bonnewagon but now when I move the heater control to "cold" the cable seems to get bound up. It won't go all the way to "cold" and if I do force it I hear a snapping sound and it goes limp. Then I hear the flapper door in the heater/AC housing thud shut and the AC airfow diminishes. Pushing it back to "heat" seems to make it OK again, then it happens all over again. Before I tear the control box out, what should I be seeing inside? The book said something about a self-adjusting cable,what might that be?

 

[Blake442]

Drop the glove box and you can watch the temp cable in action.
Check for binding, or any cracked pedestals that would lead to the cable to deflect and not operate smoothly.

 

[Bonnewagon]

Thank's Blake!

 

[Bonnewagon]

You called it Blake. Dropped the glove box and it was right in front of me. Little plastic tit broke off the arm on the door. Luckilly I had a close quarters drill and made a hole so I could use a screw and nut to secure the cable clamp to the arm. That's the adjustable feature- the clamp slides on the cable. All better now.

 

[86Cutlass383SR]

Bonnewagon, that's odd we was both messing with this today. Mine has the same problem, the little tit broke off for the cable and I planned on fixing it the same way. Small nut and bolt.

I also noticed on mine that the little cable retainer that you have to squeeze together to pull out, mine has broke loose. Can you think of any way to fix this or you think I'll have to get a differant cable?

Can you explain the *adjustable cable*. What exactly adjusts and where?

Luckily I have my dash out so I can work on it a bit better. I need to get all this fixed so I can get my dash back in.

 

[Blake442]

I had that same piece of the arm break on my Malibu wagon.
It was even better that it was 25* out and it was stuck on cool...

I just held it in place and wrapped it with a bunch of thin strips of Gorilla tape.
Worked perfect for another year or two til I stopped driving it. It was still holding and working fine when I parted it out!

 

[Bonnewagon]

86, the nut and screw worked well. I found a screw that fit through the square clip that holds the cable. Then I drilled the plastic arm a hair smaller so the screw would cut it's own threads and inserted the screw from the bottom, through the clip. Then I put a nut on top so I could tighten it like a jam nut against the arm and keep it from loosening. Am I understanding you correctly? Is that square clip that holds the cable to the arm on the door what you mean as a retainer? That is the "adjustable" part. It slides on the cable so you can get the proper range of motion on the sliding button on the face of the heater control panel. So if the "cold" position ended up an inch to the right, you can slide the clip on the cable and correct it. The book says to just force it, but I think that's how mine broke. It does clamp it pretty tightly so if yours is loose or broken, it may need to be replaced, or maybe a screwdriver forced through the middle to spread it out again. Or do you mean a retainer that holds the cable in place upstream?

 

[Blake442]

A while back Joe posted a link and part number for the replacement arm that broke.
I'm way too lazy to search for it...

 

[Bonnewagon]

I gotta add- all that AC/heater stuff is WAY too inaccessible. My lower mode was not working right and my cold AC air was getting dumped on the floor. The book said to unfasten and tilt the whole dash away from the firewall to access it. Well instead I took off the glove box again and the lower heat duct and could eyeball the vacuum motor attaching nuts. I got in there with a 1/4" ratchet and 3 extensions to reach the 3/8" nuts and removed the vacuum motor to test it and it worked, it just had fallen off the door lever. Made it right and now I'm cool again. But it took HOURS and that was a shortcut.