1979 A/C Duct problem
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Joined: Jun 2005
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From: Independence Mo.
1979 A/C Duct problem
I finally got the a/c to work on my 1979 but know the only place I am getting air out if thru the floor vents. No air is being blown out thru the dash vents. Any help or guidance on where to start looking. Thanks Gary B.
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From: CORVETTE 77 385 C.I. TEXAS
On at least later C3 the problem is that heater is the default position (no vac. or vac. leak) due to being designed in the north. Vent should be default. Very safe bet the problem is 1 OR 2:
1) The vac. line from engine is damaged from heat - a small plastic tube that goes in below the hood theft switch into wiper valley. Replacing most of engine side w/ hose will fix. OR
2) The vac. switch itself is not switching due to vac. leak as the usually plastic rivet is not holding the 2 main switch parts together well. Besides replacing, it is also possible to tighten this &/or lube w/ a thin layer of white lithium grease or vasoline to fix.
3) If you have a heater, the small vac. hose to heater hose valve underhood probably also needs replacing. Block w/o heater.
PS The design problem comment is not intended to be offensive to any of our northern friends.
1) The vac. line from engine is damaged from heat - a small plastic tube that goes in below the hood theft switch into wiper valley. Replacing most of engine side w/ hose will fix. OR
2) The vac. switch itself is not switching due to vac. leak as the usually plastic rivet is not holding the 2 main switch parts together well. Besides replacing, it is also possible to tighten this &/or lube w/ a thin layer of white lithium grease or vasoline to fix.
3) If you have a heater, the small vac. hose to heater hose valve underhood probably also needs replacing. Block w/o heater.
PS The design problem comment is not intended to be offensive to any of our northern friends.
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Joined: Jan 2000
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From: Minot ND
Corvette Manual PDF file page 192
I was not able to cut and paste from my Manual. However, I uploaded the file to my server for you to download. It is at: www.minot.com/~hlmrlm.
The file is named manual5.pdf. The information you need is on page 192.
Good luck with everything. My '79 had the same problem. It was a combination of a melted line near the distributer. I also replaced the center console control switch. It works real well now.
The file is named manual5.pdf. The information you need is on page 192.
Good luck with everything. My '79 had the same problem. It was a combination of a melted line near the distributer. I also replaced the center console control switch. It works real well now.
Last edited by Ron Major; Jul 6, 2005 at 10:55 PM. Reason: spelling
