Not blowing cold air

-
MoparMike1974 said:
R12 is not illegal, however I believe it is out of production. You can still buy it but its expensive and you have to have the proper license to purchase.
I recently had to get a license just to buy a 30lb R134 so the laws are steadily changing.
Yes you must replace the dryer when converting from 12 to 134. The proper thing to do is replace it any time the system is opened. Also, R12 and R134 dryers use different dessicants in them. Pag oil and Ester oils should not be mixed so the system needs to be flushed.
Not much room for error when servicing and AC system. Sounds like you need to hire someone.
Click to expand...

Hiring someone probably is the smartest thing to do. The entire system is about to be opened, because I have to move it all out of the way for a couple of days.

So dryer should be reached any time opening the system or anytime converting between the different types of freon. I'll get a dryer soon.
 
Dana67Dart said:
In the heater box. Well in your case the heat/ac box.

Also do you have an external valve to shut the water flow to the heater core?, Not sure if that was stock in 68 or 69.
Click to expand...

I dont think I have an external valve, if I do I dont know what it is. Are you surprised? Lol.

Heres some pictures of under the hood and my heater/ac box. I need a picture book of this car that has everything labeled. I dont do well with just reading words.

20200321_122021.jpg


20200321_122014.jpg


20200321_121902.jpg


20200321_121851.jpg


20200321_122216.jpg
 
R12 is what my brother in the A/C business refers to as liquid gold. I have converted a couple cars to R134A and other than blowing the lines out with denatured alcohol, new o rings, new reciever dryer, different refrigerant oil, and a fitting change to pump in the newer refrigerant you will never notice a change in temps compared to R12. Some people say it's not as efficient. If that means R12 can get 2-5° colder at Max cool then who cares.

I would recommend getting an A/C shop to swage new rubber lines on your old hose metal ends, because that old system probably leaks everywhere. Remember those hose lines are over 50 years old and in a dry climate.

We had the A/C lines redone on my dads lil red express. They had to cut and braze barbed fittings on the ends of the metal lines to accept the hose end crimp sleeves. Used new rubber composition Goodyear Galaxy hose. They also rebuilt the compressor.

It held full vacuum when we pumped it down and shut off the vacuum pump. My brother pumped it full of R12. You need to vac system down for an hour or 2 so the moisture in the system boils off and the pump removes it.
 
Photo #4 looks like a shutoff valve. If it is not shutting off the flow of water to the heater core the AC will not be able to cool properly.

Easy to check when engine is at temp if heat is off temp on water inlet to the valve should be hot and the outlet should be cold or a lot cooler.

Hope that makes sense
 
Dana67Dart said:
Photo #4 looks like a shutoff valve. If it is not shutting off the flow of water to the heater core the AC will not be able to cool properly.

Easy to check when engine is at temp if heat is off temp on water inlet to the valve should be hot and the outlet should be cold or a lot cooler.

Hope that makes sense
Click to expand...

So portion 1 should be hot and portion 2 should be cold?

20200321_135404.jpg
 
This looks like your Thermal Expansion Valve (TXV) for the a/c.
Is the smaller diameter line going in and exiting with the larger diameter line going into the firewall (evaporator)?
Screenshot_20200321-172434_Chrome.jpg
 
DentalDart said:
Hiring someone probably is the smartest thing to do. The entire system is about to be opened, because I have to move it all out of the way for a couple of days.

So dryer should be reached any time opening the system or anytime converting between the different types of freon. I'll get a dryer soon.
Click to expand...
Main thing is you need pull vac on the system before charging..and see if it holds.... Ac vac pump is a must. You cant just hook a can of **** to the low and have it work.
Gauges, ac vac pump and check for leaks.
I've done all my own ac work.
 
DentalDart said:
So portion 1 should be hot and portion 2 should be cold
Click to expand...
Yes. It looks like the valve is vacuum controlled. You could hook your pistol grip hand vacuume pump to the canister and see if it moves the diafram and the valve actuator.
 
Dana and DentalDart, you guys are referring to the heater hoses and control, right? Not A/C?
 
moparmat2000 said:
R12 is what my brother in the A/C business refers to as liquid gold. I have converted a couple cars to R134A and other than blowing the lines out with denatured alcohol, new o rings, new reciever dryer, different refrigerant oil, and a fitting change to pump in the newer refrigerant you will never notice a change in temps compared to R12. Some people say it's not as efficient. If that means R12 can get 2-5° colder at Max cool then who cares.

I would recommend getting an A/C shop to swage new rubber lines on your old hose metal ends, because that old system probably leaks everywhere. Remember those hose lines are over 50 years old and in a dry climate.

We had the A/C lines redone on my dads lil red express. They had to cut and braze barbed fittings on the ends of the metal lines to accept the hose end crimp sleeves. Used new rubber composition Goodyear Galaxy hose. They also rebuilt the compressor.

It held full vacuum when we pumped it down and shut off the vacuum pump. My brother pumped it full of R12. You need to vac system down for an hour or 2 so the moisture in the system boils off and the pump removes it.
Click to expand...

Where do the O rings go? I've read about new hoses, how much did you pay for hoses? The kits find are like 200 if I made them myself

I think the fitting I installed already allows me to pump in R134A into my system.
 
You have to find an auto A/C shop that rebuilds the existing lines you have. They reuse your metal ends and fittings, and cut the old hose off. They braze a barbed fitting to your metal line to accept the new rubber hose. Then they use a crimp sleeve over the new hose and barb end. Your original ends and fittings are reused. They do it this way because the way the chrysler lines are done from the factory cannot be duplicated when changing to new rubber hoses. The O rings go on the end of the metal lines theres a spot for them. You will see the old ones on there when you take the fittings loose and disconnect the lines.
 
Dana67Dart said:
Yes. It looks like the valve is vacuum controlled. You could hook your pistol grip hand vacuume pump to the canister and see if it moves the diafram and the valve actuator.
Click to expand...

I took the vac line off and I can get it to click on and off. Add vac and pops open/closed, press vac air in and pops closed/open.

20200321_162440.jpg
 
Opened this line (low side? ) and all kinds of stuff freon/air started shooting out.

20200321_161404.jpg
 
Looks like you twisted the copper sensing tube that goes to the orifice valve. I woulda left that alone and cracked loose one of the fittings to the dryer.

Screenshot_20200321-184000_Samsung Internet.jpg
 
DentalDart said:
Well I didnt drain anything out of my system originally because there wasnt anything in there.
Click to expand...

There is mineral oil dispersed through the system, as well as in the compressor. How deep a vacuum did you achieve/how long did you run the vacuum pump?
 
Demonic said:
There is mineral oil dispersed through the system, as well as in the compressor. How deep a vacuum did you achieve/how long did you run the vacuum pump?
Click to expand...

Just now? I just used a hand vac pump to see if the valve open and closed. I've never ran an actual ac vacuum or anything.
 
The purpose of pulling a vacuum on the system(vacating, evacuating) is to remove all moisture from the system. This is usually done for 20-30 minutes and requires a special motorized pump to do it. Most of the advice here is good and is all standard stuff for a real A/C man. The problem I think you are going to have is finding a good man that is willing to work on it.
 
I have a vacuum pump to evacuate the system... also have a set of gauges....

i think the R12 and R134 use different fitting...i know my pump and gauges will work on R134 system...
 
A/C service is simpler than a lot of people make it out. All you really need to know is how to read gauges and what they read MEAN. You can see everything from them, including a restricted system or a bad compressor. If you buy R12, be VERY careful, as there are a LOT of substitutes on the market, including some PROPANE based refrigerants. No, I'm not kidding. Propane will cool in the system, but I don't think I have to tell you why NOT to use it. lol As along as you keep everything clean, use new O-rings everywhere and take your time, I think it's in your wheelhouse of skill to do. It's really not that hard.

Look at it this way. I made my living for a time doing A/C work. If I can do it, anybody can.
 
70aarcuda said:
I have a vacuum pump to evacuate the system... also have a set of gauges....

i think the R12 and R134 use different fitting...i know my pump and gauges will work on R134 system...
Click to expand...

I have the fitting for R134A :)

You sir do have everything! One day if I'm lucky I'll have it all too.
 
Murray said:
The purpose of pulling a vacuum on the system(vacating, evacuating) is to remove all moisture from the system. This is usually done for 20-30 minutes and requires a special motorized pump to do it. Most of the advice here is good and is all standard stuff for a real A/C man. The problem I think you are going to have is finding a good man that is willing to work on it.
Click to expand...

Dont need a man when I got FABO :poke: Lol you guys are all awesome really with the wealth of knowledge.

RustyRatRod said:
A/C service is simpler than a lot of people make it out. All you really need to know is how to read gauges and what they read MEAN. You can see everything from them, including a restricted system or a bad compressor. If you buy R12, be VERY careful, as there are a LOT of substitutes on the market, including some PROPANE based refrigerants. No, I'm not kidding. Propane will cool in the system, but I don't think I have to tell you why NOT to use it. lol As along as you keep everything clean, use new O-rings everywhere and take your time, I think it's in your wheelhouse of skill to do. It's really not that hard.

Look at it this way. I made my living for a time doing A/C work. If I can do it, anybody can.
Click to expand...

I think you over estimate my wheel house. I'm not the brightest crayon in the box:p, but I dont ever mind trying to get something done in my own garage before calling in the professionals. How else am I to learn and teach the youngins this information in 30yrs if I dont?

I think after we get the motor put back together this week I'll look into the A/C more. I'd love to have A/C this summer for slurpee runs.
 
You must log in or register to reply here.
-

Back
Top