A/C Suggestions
Thread Starter
Racer
Joined: Dec 2001
Posts: 352
Likes: 0
From: SELMA AL
A/C Suggestions
I have a 66 SB cpe with A/C, and I just can't get it to blow real cold. It puts out some cool air at the vent but not much. I have had it worked on, and they found a small seal leak in the compressor, but that was it. Fixed and recharged, still just cool.
Is there anything else to look for. Condensor and evaportator are about 4 yrs old, with virtually no miles.
It's getting hot and summer is coming. Didn't they really work ok when new, or is that dreaming?
Look forward to hearing from all of you.
Frac :) GB
Is there anything else to look for. Condensor and evaportator are about 4 yrs old, with virtually no miles.
It's getting hot and summer is coming. Didn't they really work ok when new, or is that dreaming?
Look forward to hearing from all of you.
Frac :) GB
Le Mans Master
Joined: Jan 2000
Posts: 8,918
Likes: 27
From: New Hill NC
Re: A/C Suggestions (FRAC)
That thing should freeze your kahonies off. There is an extensive section in the 66 service manual. Any good A/C shop should be able to tell you what is going on by doing some simple checks.
Le Mans Master
Joined: Jan 2002
Posts: 8,913
Likes: 283
Re: A/C Suggestions (wombvette)
Quote
"That thing should freeze your kahonies off"
I agree.
Is it freezing up anywere? Look under the hood and note for frosty lines.
I am looking at the shop manual for my 65 and it shows an air door to divert the air across the evaporator. Is this shuting all the way? Did not see a heater core shut off valve.
Could be a POA valve or the filter in the expansion valve. Just a guess I am no AC pro but I had a similar problem with my 70 C-20 truck that I just finished getting the AC going in. Turned out to be the POA valve and the expansion valve (restricted filter). I installed an electric POA valve that cycles the compressor on and off. Blows air down to 37*. Nice and cold now.
Mark
"That thing should freeze your kahonies off"
I agree.
Is it freezing up anywere? Look under the hood and note for frosty lines.
I am looking at the shop manual for my 65 and it shows an air door to divert the air across the evaporator. Is this shuting all the way? Did not see a heater core shut off valve.
Could be a POA valve or the filter in the expansion valve. Just a guess I am no AC pro but I had a similar problem with my 70 C-20 truck that I just finished getting the AC going in. Turned out to be the POA valve and the expansion valve (restricted filter). I installed an electric POA valve that cycles the compressor on and off. Blows air down to 37*. Nice and cold now.
Mark
Drifting
Joined: Feb 1999
Posts: 1,260
Likes: 5
From: Brandon FL
Re: A/C Suggestions (ghostrider20)
Could be a POA valve or the filter in the expansion valve. Just a guess I am no AC pro but I had a similar problem with my 70 C-20 truck that I just finished getting the AC going in. Turned out to be the POA valve and the expansion valve (restricted filter). I installed an electric POA valve that cycles the compressor on and off. Blows air down to 37*. Nice and cold now.
There is a fix for this. Similar to the POA update. With this update you remove the innards of the STV, and install a thermostat that cycles the compressor. Very much like most of today's systems operate. I installed one on my 65 coupe and it worked perfectly.
The previous posts are correct. These midyear A/C units are capable of freezing meat when operating properly.
Thread Starter
Racer
Joined: Dec 2001
Posts: 352
Likes: 0
From: SELMA AL
Re: A/C Suggestions (FRAC)
Thanks, I had forgotten about the POA valve. My early consultant on the car suggested that I changed out to the 67 POA valve from the get go, and I never got "around tuit".
It doesn't cool enough to freeze up that fast, so it must be one of the other things.
I'll see if I can get my ace mechanic on the fix with your suggestions.
I'm glad to hear that what it should do, so at least I know I am not chasing my tail on this.
I plan on driving it to BG for the 50th in late June, and take my wife. If it is not cooling, I won't get past B'ham.
Thanks again.
Frac :) GB
It doesn't cool enough to freeze up that fast, so it must be one of the other things.
I'll see if I can get my ace mechanic on the fix with your suggestions.
I'm glad to hear that what it should do, so at least I know I am not chasing my tail on this.
I plan on driving it to BG for the 50th in late June, and take my wife. If it is not cooling, I won't get past B'ham.
Thanks again.
Frac :) GB
Le Mans Master
Joined: Jan 2002
Posts: 8,913
Likes: 283
Re: A/C Suggestions (FRAC)
Like mentioned you do not have a POA valve, but a STV (suction throttling valve). There should be an expansion valve with a temp probe going to the evaporator.
1- You could replace your stv with a POA or the electric conversion kit. I paid around $125.00 for the unit that replaces the the POA or in your case the STV.
It does not look stock so if that is a concearn maybe a POA may be better for period correct, although my supplier noted that allot of new POA valves are junk. The cost was almost the same for either units.
Mark
1- You could replace your stv with a POA or the electric conversion kit. I paid around $125.00 for the unit that replaces the the POA or in your case the STV.
It does not look stock so if that is a concearn maybe a POA may be better for period correct, although my supplier noted that allot of new POA valves are junk. The cost was almost the same for either units.
Mark
Burning Brakes
Joined: Mar 2001
Posts: 995
Likes: 0
From: Alhambra CA
Re: A/C Suggestions (FRAC)
What refrigerant did they charge the system with???
I have heard that some conversions will not get nearly as cold as they will when charged with R-12..
My system has R-12 and will freeze you out if not controled.
Check system pressures and that should tell you the condition of the refrigerant controls.
If that valve is stuck closed, suction side pressure will be very low.
Head pressure will be high.
Make sure you have a full charge some conversions are forced to run a low charge if using R134 as the head pressures are higher.
Tony
[Modified by pittsaj, 9:15 PM 5/14/2003]
I have heard that some conversions will not get nearly as cold as they will when charged with R-12..
My system has R-12 and will freeze you out if not controled.
Check system pressures and that should tell you the condition of the refrigerant controls.
If that valve is stuck closed, suction side pressure will be very low.
Head pressure will be high.
Make sure you have a full charge some conversions are forced to run a low charge if using R134 as the head pressures are higher.
Tony
[Modified by pittsaj, 9:15 PM 5/14/2003]
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