I believe I just "fried" my A/C compressor on my 68 Riv, with Climate control. Need some advice. The system was empty for freon, but as the temperature does not call for use of A/C, I used the system in heater mode only. After some time the unmistakable smell of burned cable was noticed. Stopped the car and noticed a burned A/C clutch etc. Found out that I have a live connection to the clutch all the time when the fan is operating. To me it seems like the compressor are operating all the time, even when the system is in heating mode. :rant: Can this be correct? Regards, Per. :ball: :ball:
That's not correct, Per. The switch is prolly broke in the dash.....it's part of the heater/ac controls. In order to fix this correctly, you will need to fix that and install a good compressor. I would flush the entire system and drain the compressor first before installing it and then add a full charge of oil to the system which I think should be around 10 ozs. If you plan on using 134 then use ester oil, it's compatible with both r134 and r12. I won't mention how well hc-12 propane based refrigerant (duracool)worked for me......I'm not up to the arguement that I'm certain will follow that declaration. :grin: :bglasses:
Per, Joe is right.......does your clutch engage even when you have it on vent? When I read your post I was under the assumption someone ran a wire from your fan motor to the a/c clutch. I forgot what year Riv you have, but in '67 the clutch should not come on in defrost........I think that changed in later years but I don't know for sure maybe '68 or '69? :bglasses:
On the early Automatic Climate Controls (even in 66 and 67), compressors operate all the time (exept in off position) when the outside temperature is above ~45F. If it still operates when it's freezing outside, you will need to replace the ambient switch. On 68 Rivieras, it is located just beside the cooling hose for the blower motor. If you run out of refrigerant, It's a good idea to disconnect the compressor as there is no thermal limiter on pre-71 cars. I'd also disconnect it in the cold season because it's harder to notice if there is a refrigerant loss... Later ACC systems have a Vent position on which the compressor doesn't operate. Some 1974 and all 1975 and newer Automatic Climate Controls have an Economy mode that allows automatic operation (and heating) but cuts the compressor. It will operate on all the other settings (exept off!) above 40F. My 67 Riv doesn't have ACC so the compressor runs only in the A/C and Recirculation modes. Even if I can switch it manually, I dont want to burn the compressor if it overheats, so when I replaced it, I used a newer compressor with a superheat switch on it's head and I added a thermal limiter from a 76 Buick. When you'll replace your compressor, be sure to have the correct pulley dimension, 67-72 Riviera GS models and any 67 and newer Buick with an A-6 compressor and 3.42 rear axle have a larger pulley.
Thanks. Ambient temp at the moment around 50, so the compressor would still have been working :af: I'll better install an in-line on/off switch for the clutch later. The only "major" thing left on the car was the ACC. Had planned to get all the vacuum hoses installed this winter. Recon I now need a complete rebuild ou: Anyway, Merry X-mas & a peacefull new year to you all. Per. :beer :beer
Per, I've never shipped parts internationally, but I may have what you need to convert your ACC to manual A/C. From what I've heard and read about it it's a very unreliable system. I never got into ACC on old Rivs and don't know what's involved to convert it, but I have some extra '67 Riv a/c parts and if you want to try I may have the parts you would need........let me know. :bglasses:
Thanks for the offer Joe. I would have loved to have the original ACC working, and have been collecting parts for it from the US for more than a year now. (I even got hold of the "Buick '66 '67 '68 Auto Climate Control diagnosis guide", in addition to the shop & part manual). So l'll try to get it up and running first. (If anybody need something from the manuals, I'll try to scan it). Can understand that the system was not very good, there is fare to many vacuum hoses, switches, releys etc all over the place for it to be reliable. Anyway,I just want to try to get it working "for the heck of it". When/if I give up, I'll give you a shout. All the best, Per. :beer :beer
Joe, ACC systems changed every year back then and the 67 and 68 system are very different! Their operation is similar but almost every part was changed! I might be interested in your 67 ACC parts if they are for the late type 67 ACC (yes, there were two ACC systems that year!)
Phil, the parts I offered Per were non-ACC parts.........all I have is a few extra standard A/C parts.
Joe, I should have read your post better! I have parted out a 67 with ACC and I hoped to install it in mine (I like trouble!) but there were so many defective parts in it that I changed my mind! Automatic a/c systems are quite complicated but switching from automatic a/c to manual a/c is also complicated. The wiring harnesses are different on ACC cars. The 68 dashes and are completely different from the 67 and the heater box isn't the same. The control panels are exclusive to the 68 models too. The good thing about the 68 ACC system is that it was more reliable and more simple than the 67 system. Parts are hard to get because each GM division had different automatic systems, and the Buick system was not the best or the most popular, dealers were probably afraid of them, I heard that they were unable to make the 66-67 system work properly under warranty! Most of the other automatic A/C systems in the other GM divisions used electronic temperature sensors while the Buick sensors were mechanical. In 71, all GM divisions shared the same more reliable system which had very few modifications during the seventies.
Joe, I somehow agree with you. It sounded like a very "fancy" option when I found out that a car from 1968 had a ACC. After looking into it in more details and trying to find out why it did not work, the joy rapedly faded. For sure, there would have been nobody locally to fix it. When I got it, most of the parts where missing, including all vacuum hoses, and it was operating by manually adjusting the unit from under the hood. AND, since it probably have not operated for the last +30 years, that's excactly why I want to get it working now. :Brow: BTW, If anybody have a good spare "Thermostatic Vacuum Regulator", (that's the "white plastic" dingi that are located behind the dashpad on the passenger side, having three small vacuum hose connectors, one temp. cable and two 1/2" air hose connectors), I would be very much interested. Per. :beer :beer
