Hey everybody, The top vents on my '72 Riv have not worked since I got her. I believe the AC is not working but that is a different story and I just wanted to get the vents working first. Would any of you advise a process for diagnosis?
I assume you are talking about the defrost/fog function? The vents next to the windshield? I'm going to assume your vent system is similar to the one in my 74 Lesabre. That is controlled by a vacuum switch. That switch was made of plastic which cracks over time. Once it cracks it won't hold vacuum and your defrost won't work anymore. In my case I discovered this while changing the heater core. I wasn't able to find a replacement, but I was able to glue it up. Note this will be a huge job to get to it, almost as much work as changing a heater core. That all being said, someone may come along and say the Riv vent system is totally different. I will check my 74 Buick shop manual later tonight and let you know if no one else chimes in. (I know you have a 72 but it's unlikely there will be significant differences between the two years.)
Ah thanks for the info! It's actually not just the window defogger but all of the vents in the dash too. The only place that air comes out is the lower vent above the driveshaft hump. I will look for the switch in the manuals that I have to get the location.
I just read your other thread “ Where does this hose go?” I wonder, with the hose now attached to the correct port, has your vent issue been resolved?
Had the same problem in my '69 Skylark . The hose was off the canister under the hood. Having air come out of the tunnel outlets seems to be the 'default'setting.
Haha! I don't believe it - it worked!!! The vents blew a whole load of dust and crap in my face that was probably years old and will now give me some horrible disease but the vents work!! Thanks so much James, great suggestion, really appreciate it! Now I just need to get the AC reinstated which my workshop can do.
As I posted earlier, most of the time it is because the vacuum line is disconnected for one reason or another.
Hi, yes thank you for posting that, it was just that I did not know where the vacuum line was. Good to know and I am glad it was that easy. Just need to get the AC recommissioned now
I’m glad that worked out so well. Your AC refrigerant system may need to be leak tested , and evacuated with a vacuum pump. Before adding refrigerant.. They’re many AC experts on this board that can walk you through those steps. I’m very confident that you’re capable, with their guidance. Or, your workshop can do as you say.
