heater control problems need help.
Burning Brakes
Joined: Aug 2004
Posts: 971
Likes: 7
From: roanoke va
Might be the blower motor resistor bad causeing the high speed only. It is on the out side of the heater box. Sometimes you can take it out and find a broken/ burnt wire coil attached. My 72 only had high speed and it had a broken/ burnt coil.
Might be a vacum line disconected going to the heater control. The doors are operated by vacum.
Might be a vacum line disconected going to the heater control. The doors are operated by vacum.
Thread Starter
Instructor
Joined: Oct 1999
Posts: 182
Likes: 0
From: SW Oklahoma
Problem with blower was the relay. As a side the relay crosses over to a 77-70 Impala as it is not corvette only.
Now to tackle the problem with it not blowing out the vent or drfog--just heat. Looked at it very quickly the other day. Took the side panels off the consol and nothing looks out of place. All lines seem to be hooked up etc. All levers move. Any quick tests you guys know of?
Now to tackle the problem with it not blowing out the vent or drfog--just heat. Looked at it very quickly the other day. Took the side panels off the consol and nothing looks out of place. All lines seem to be hooked up etc. All levers move. Any quick tests you guys know of?
Thread Starter
Instructor
Joined: Oct 1999
Posts: 182
Likes: 0
From: SW Oklahoma
Last follow up. I took the side panels off the consol. The vacumem mixer for the heater, vent and defog will come out by itself with a small screwdriver. Took it apart and did not see anything wrong with it. Checked the varous doors with a vacum pump and they all worked. I went back to the switch and cleaned it up. The rubber gasket looked good. In taking it apart I broke the snap plug that holds it together. it seemed to me that it was not sealing properly -it sandwitches the gasket between the housing. I drilled the center hole bigger and ground down the center stud to tighten it up then used a short screw with thread locker to reassemble it. I put some light grease on the gasket prior to assembling it I might add. It worked fine. Hope this helps someone else out who has similar problems. Now I just need to find a new switch in case this one does not last long.
Drifting
Joined: May 2005
Posts: 1,629
Likes: 4
From: Somers CT
Originally Posted by BobKap7
Where can I find a vacume diagram for the "76?
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