I have a 1968 buick with factory air.. The air just doesn't seem like it should. How does original a/c unit's match up with the a/c unit's of today? My a/c Blows ice cold and I recently put a new blower motor in, but... It Isn't blowing out the vents hard enough to cool the car let along me. I did feel air blowing out the fender with the car shut off and just the blower motor running though? Maybe the air isn't all getting pushed into the box?
when it's right it will freeze you out of the car. Make sure all you ducts are hooked up and there are no air leaks. Then make sure you're not icing up the evaporator. That will kill the airflow quickly.
Your AC system is controlled by vacuum, so it's possible that there is a problem with either the lines running to each damper/flapper door. If a damper is not opening/closing properly which wouldn't allow air to flow freely to the desired duct. With 40 year old vacuum lines, it would not surprise me that at least one is leaking. Good luck tracing that down, since there are about 7 or 8 separate ones. Your dash controller could also be faulty as wel.
The OEM AC system in your 68 should be roughly comparable to a meat locker below ambient temps of 80-82 degrees or so. Above ambient 82-85 degrees it will keep you very cool, but your fuel mileage will decrease almost exponentially with the temperature at the vents. :grin: To reiterate what 70aqua_custom said: "when it's right it will freeze you out of the car. Make sure all you ducts are hooked up and there are no air leaks. Then make sure you're not icing up the evaporator. That will kill the airflow quickly. After 40 years, the system could very well have ingested enough dust, dirt and debris to block the airflow past the evaporator. That is always a concern with "old" cars. My 1985 Lincoln Mark VII needs the evaporator case pulled for cleaning due to crappy air flow at 24 years.
for those that don't know, on an a-body, it is possible to remove the blower resistor from the evaporator housing and gain access to clean the evaporator. I use a bug/chemical sprayer and a flashlight. The wand from the sprayer will reach inside and get close to the evaporator. The dirt and excess solution drains out the bottom. I use a non foaming coil cleaner called Calclean but some greased lightning, 409 or similar will work fine. Mine was spotless and it only took a few minutes.
Well guess I'll be taking a look for these problem's. To get to the evaporator i take off the inner fender well on the passenger side correct?
not really, http://www.v8buick.com/showthread.php?t=149908 but I don't understand why you need to get to the evaporator?
there are a couple of ways to tell is your evap is freezing up. If it's freezing up, you will see frost or ice on the outlet of the evap before it goes into the POA valve. That is the large aluminum pipe that makes a 180 turn. Sometimes the ice will melt when you idle but it will freeze when you're going down the road. If you have great airflow whe you first turn on the A/C and then it gradually reduces, it's icing up. Another way to tell is there will be a large puddle of water under the right front of the car about a half hour after you park it. You don't want to take the A/C box apart and run it to find out if it's icing up.
Ok if those are the signs to look for it's def freezing up. What should I do now to fix this? Even when I fist start the car and turn on the a/c it still doesn't feel like it's blowing very hard. I'll check and make sure all the correct door's are open today.
There is no combination of air diverter door positions that will block the airflow. The most likely reason for poor airflow is years of dust and dirt plastered on the evaporator, assuming your ducts are in good shape. This will also cause icing.
The duct's are in great shape as far as I can tell. We replaced the blower motor awhile back.. it barely spits air out the vent's unfortunately, but it does blow very cold. I need to clean the evaporator then?
Probably. Pull the blower resistor like 70aqua_custom suggested and see if you can see the evaporator at all. It would be good to verify the problem before you open it up. The only problem I see with cleaning it through the resistor hole is that anything that doesn't go out the drain will lay at the bottom of the evap and hold water. That could lead to corrosion, although if there is a lot of gunk in there now, it's holding water already.o No:
Pulled the blower resistor.. can't see the evap from their I could see a door directly behind it which was closed though.
it isn't easy but with some light and the right angle, you can see the evap to the right when looking through the hole. Trust me, it's in there. If all you see is black, it's dirty and needs to be cleaned.
