AC not working

[Carmine]

Hi everyone. I have a '64 SS that came with factory a/c. It's not working properly. It doesn't blow cold enough air. I'm not trying to compare it to modern day car a/c, but this just isn't working properly. The fan/blower works fine and when you push down the one lever for the a/c, the compressor engages and the engine rpm decreases slightly. I had it to a mechanic who replaced some type of vacuum switch controlling the heat and a/c. He said that the previous owner converted it over to the modern refrigerant and it was full. He seems to think that everything is working properly, but I don't. The air will get slightly cooler but not cold. With winter coming, I certainly don't need the a/c or will even be driving the car much longer. I spoke with the mechanic the other day and told him of my concerns. He is a real decent guy and said to bring it back in the spring and he'll check it some more. I know little to nothing about a/c. I guess there are 3-4 main parts to it. Based on my description, is there something we should be looking at again?? Some thing I can gently pass along to him?? Thank you, Carmine.

 

[Nuts]

Carmine,

I know that some will say they could cool a side of beef with the A/C in there 6o's Chevy, with original A/C. Mine does an okay job, but nowhere near anything like modern A/C. I changed mine over to the new refrigerant one time and changed it right back to R12, because it didn't work nearly as well on that than. It's hard to find shops that know much about the "old" A/C systems, but don't give up the battle, they will do a good job when setup correctly.

Bill

 

[blkblk63ss]

carmine , on those older system,s if i remember correctly , compressor clutch will be engaged by voltage from switch directly and not by a low pressure switch which then does provide voltage as most modern system's are . so if pressure's are ok, that would indicate system is full and no leak's and everything is correct as as far as component's, like compressor , condensor, valve's ,dryer, ect. I would check the temp door adjustment to see if it is closing properly on ac mode , and the door seal's are ok. You have factory air and i have not worked on those system's so i can't tell you where that adjustment is , but your mechanic could find it most likely.Hope this help's.Like the mech said, hard to tell going into colder time of year to check an ac properly. You stated you was not happy with temp, what is your temp coming out of vent's????

 

[Ronnie Russell]

I don't know squat about a.c. but back in the day I worked at parts stores and our biggest seller for a.c. stuff was called a suction throttling valve for the GM cars. Located behind passenger front fender.. The valve itself was cheap, many mechanics bought them by the dozen, however, labor charge was huge.

 

[blkblk63ss]

I don't know squat about a.c. but back in the day I worked at parts stores and our biggest seller for a.c. stuff was called a suction throttling valve for the GM cars. Located behind passenger front fender.. The valve itself was cheap, many mechanics bought them by the dozen, however, labor charge was huge.

Thank's ronnie ,
As i mentioned pressure's should indicate this i would think on that system , but i would rule not that out completely.they were a problem on older f$$d car's also.

 

[Don Jacks]

Given that todays a/c systems are so much simpler and lighter,no Suction throttling valve,no poa valve,no expansion valve,it makes zero sense,in my view to use those antiquated systems anymore on anything but a restored car that's rarely driiven.On a car that is to be used and enjoyed often,go with a modern system and forget the problems.My dad's first car with a./c was a 1961 Brookwood wagon,followed by a 1963 Impala wagon,followed by a 65 Impala sedan.All three units worked very well at the time,especially since the cars were several years old when he got them.In those days,parts were not a problem,today they are either non-existant,or very expensive,and dont work very well with R-134.While there is some R-12 still around,Its hard to find,and expensive when you do.I have years of automotive repair under this old belt,and that includes a/c work.About 5 years ago ,we did a repair job on aa 1970 Olds Cutlass for a customer that had let the car sit for several years.While the factory had by then eliminated,or found ut that it wasnt needed,the suction throttling valve,it still had that blasted poa [pos is more approiate]on it,and I lliked to have never found a replacement for the one that had failed,and the car simply did not work that well.I would have "moderenized" the system,but the customer wanted it to be stock,so all he can do is live with it.Carmine,you may be in thge same boat .On the other hand,Winters coming,and this could make for a great winter project.Best of luck with it.

 

[Carmine]

Thank you everyone for your responses. When I first brought this car up from Louisiana, the owner said the a/c worked fine. This was Feb. and at that time I didn't need it in NY. I did try the blower switch and a/c lever and everything appeared to engage and work ok I guess. It was later, maybe May, that I tried it again. Everything engaged and the a/c didn't seem much colder then the outside air. Quite honestly, I didn't notice much difference. I waited until mid-summer when the temps started getting high. Tried it again and the air was no cooler then the outside air. Took it to the mechanic who is an older gentleman and said he had worked on these before and could fix this one. A few days later I stopped by and he said that the PO had changed the refrigerant to the modern stuff. He said that it was full and no leaks detected but it still didn't blow cold air and would require further checking. A few more days went by and I stopped by his shop again. He showed what I describe as a vacuum switch, with a brass plunger and I believe two vacuum ports. This might be what some are referring to as a "suction throttling valve". He said this controls the heat and a/c depending on what is called for. He showed me the plunger which appeared to be stuck. He felt this was the problem. I've never seen this part before and didn't know it existed. He asked if I could get a new one and I didn't have a clue if I could or not. Went to the internet and found a company in Texas who apparently manufacture these. Took a pic of it and went to the mechanic and showed him. He said that would work and I ordered one. I'm not complaining, should be happy I was able to get it, but this part was expensive; $95.00. Took the car back again and left it. I didn't know it at the time, but this part gets installed on the passenger side, up under the dash someplace. I think he had to take the glove box out. He called that the car was done and I went to pick it up. He said everything worked fine. Guess I got caught up in the excitement of having it fixed, so I left with the car, without trying it first. Shortly down the road, I tried it and maybe, just maybe, it was a little bit better. Certainly not what I had expected. I drove it home and tried it several different times, several ways. Still not blowing cold air to my satisfaction. A few weeks later, I returned to the mechanic and told him of my displeasure. He said I could bring it back and he would continue to try and fix it. He feels that whatever is not working properly, is minor in nature. He feels we're close to having it operate properly. Winter is approaching so I told him I'd return in the Spring with the car.

This car came with factory air and it's important to me that it operate properly. I've read stories where some cars have sat for 20-30 yrs. and when started, the a/c works like new. Guess it's the luck of the draw. I don't expect the same result from this as I get from my new pickup truck, but this isn't even close for me. Really not acceptable. Interesting that one thread mentioned checking the temp. door adj. and the door seals. If I remember correctly, the mechanic said this vacuum switch controlled that. Will have to ask him again about that.

Sorry I was a little winded with this. I wanted to explain to everyone a little of its history. If anyone recalls anything else, I'm all ears. Thank you again, Carmine.

 

[Nutts62]

I shopped around in here a bit to see if I could find some articles about this Air Conditioning thing in the Bel Air. It worked great last year, this year just blowing ambient air. Compressor is coming on and the fan when you pull the lever, but not getting that refreshing cool breeze. This is probably not an issue I can resolve myself. But you never know, maybe there is just a button I can reset and things will start working normally again. My step dad was talking about this wonder throttle valve in the fender that he said was always a problem in the past. Couldn't find anything about a throttling valve in here.

 

[303Radar]

Whats the pressure inside the lines? May have a cracked compressor case or hoses.

 

[Don Jacks]

Those old compressors had a nasty habit of the front seal failure due to lack of use in colder weather.This was the reason that many owners manuals said to run the a/c unit for at least 15 minutes monthly.Get an A/C pressure gauge set up and check the pressures.On a 70 degree day your low pressure should be about 30 psi on the low side and about 180 on the high side.If it's where it should be then there's likely an expansion valve,or a POA valve issue,if the pressures are low,there's likely a leak somewhere,and it will need recharging.Take a picture of the fittings and post them here if you're not sure about the type of Freon[R-12 or 134] that you'll need.It was almost routine to have to recharge the A/C on these older units on a yearly basis.

 

[Nutts62]

What is this wonderful item that is tucked up into the right fender well in the most impossible place to to work on? With all the oil and grime around I suppose it could be leaking all my precious cold air making material out maybe? Also there is that wire that opens and closes some valve in it. What direction does it need to be in for proper operation?

I haven't attached any gauges to it yet as I don't have any. But will get some with my R12a order. I am guessing R12a will work fine hopefully? Unless I take it the shop and have them top off the freon..

 

[Don Jacks]

Yes you have R-12,and good luck finding it!When you do,,,,,,,,,,,be prepared for it to be expensive ! Now that I've got the bad news out of the way,IF [and only if] the system has lost it's charge,take to a shop and have it converted to the much cheaper,much easier to find 134A.Have them put a leak checking dye in it when they recharge the system.A large leak will show up quickly[anywhere from two days to 2 weeks.a smaller leak may last you all season,but the dye will leave a trace,often visable to the naked eye,but certainly under a black light.That valve is known as a POA valve,and yes,that cable should be hooked up,but it hasn't in years and the system worked fine.They don't usually leak but can fail internally.Do not concern your self with it right now,unless the system is basicly full of Freon,but is not circulating the Freon.This is where the A/C shop comes in.R-12 and 134-A are not compatable.They have to have separate gauge fittings,seperate vacuum and recovery machines,ect.There are fittings availeable,and it might be a good idea to change oil in the compressor as well.Let's start with the pressure readings first.

 

[MRHP]

I used a r12 drop in replacement a few weeks ago on an early land cruiser. Vents blowing 36 degrees. Got it on amazon. I have used similar products before with the same results. I think it was r12a.

 

[MRHP]

RedTek brand R12a.

 

[Don Jacks]

Good,Thanks Brian,that'll work!

 

[Carmine]

WOW. Can't believe how old this thread is. If I didn't mention it already, I sold the '64 SS. Great car. Solid. Nice driver. Just wasn't what I wanted. I'm very happy with my '62 409 SS clone. Can really relate to it. It's a keeper. Going to let the kids fight over it LOL, Carmine.

 

[63impalass409]

My kids and wife are already fighting over my 4 cars and I'm only 47 so I told them I will try to sell everyone of them before I die and party the money away so they would shut up!!

 

[blkblk63ss]

My kids and wife are already fighting over my 4 cars and I'm only 47 so I told them I will try to sell everyone of them before I die and party the money away so they would shut up!!

So when you gonna die????? I mean how are you going to know so you have time to get them sold, and then feel good enough to party!!!!

 

[Nutts62]

Sorry I will be digging up old threads for a long time. It's all I have for the history of the 62. I am quite impressed with dad's write up on the time we spent building up the Buick for my son. I need to figure out a way to capture all this information out of the wonderful site.. Thanks for everyones feedback and input. I will purchase a R12a kit off of amazon this week. It will have some gauges in it I hope. Will get some numbers and go from there. Money is tight right now as I am pouring it into items on my truck that need repaired before the trip to the convention.. Shocks, tires, tie rod crap. Things I have have just kind of let fall to the waste side since I haven't been traveling much with the truck under loaded conditions.

 

[61BUBBLE348]

Nutts 62, no problems, with all the old timers around here it will bring back new memories.

bring em forward and ask as may questions you want, Bill posted regularly and was teaching and learning from us all.