Want to fix my A/C?

[salhi_aemr]

My 73 came with AC from Factory but the AC compressor is locked. All the lines and everything are there.

What compressor everyone recommends or should I rebuild mine? also what else do I need to change in order to make my A/C work?

when I turn the fan on in the car the air blows good? so could it be just the compressor or I need to change the whole lines and anything else?

also what is the cost am looking at from labor to parts?

 

[Jeff73Mach1]

You probably need to change everything. Unfortunately when an AC unit fails, the crap that gets into the lines can be very hard to flush out completely. So what will happen is you'll replace what you think is bad and a bit of trash will find its way into your new compressor and then it fails and contaminates the system with a fresh round of trash.

Also, with the changeover form R 12, your old system will be less effective.

What I would recommend would be something along this line

http://www.classicautoair.com/?q=71_73_Mustang_Cougar_Air_Conditioning_Ford_Mercury_AC.html

You can read their installation manual and see if it is something you are comfortable with.

I've had no problems with my system, but I do know others that have posted that they did. Do your research.

 

[72HCODE]

Jeff73Mach1 is correct usually you need to change everything or you try and blow it out sometimes you get lucky.

I do not recommend an aftermarket system nothing works as well as the OEM factory A/C even if you need to totally restore it.

you would want the replace it with the same compressor unless you want extra work making an aftermarket compressor fit.

our cars used a YORK compressor and you can get a rebuild, you want to get the rebuild with the magnetic clutch and pulley installed and it will run about 400$+ shipping.

when replacing the compressor you will need to change the dryer, which is about 20-50$.

if your system is original and uses R-12 and has the original fittings then keep the R-12 you can still get it, its just a little more expensive.

if your system has been changed to R-134 then stick with the new gas.

depending on condition there are other things in the system that might need replacement; condenser, evaporator core, expansion valve, hoses.

in my area a standard A/C service is about 150-200$ that is just adding oil, vacuuming the system and filling with freon, and does not cover repairs.

a major overhaul on the A/C system can run over 800-1000$ just in parts, before you add labor.

labor will vary in my area labor is now 155$ an hour.

some places can be 65$ or less.

the fan blowing has nothing to do with the actual A/C system. the heating and cooling systems are separate and the fan just blows the air out.

there are many electrical parts to the system that need to be inspected and checked for function. there is a A/C compressor switch when you use the top lever and set it to cool using the vents and max settings.

there is a Evaporator Freeze sensor that needs to be checked that it kicks off and on to prevent the compressor from locking up.

rebuilding the york compressor may require special tools so it is better and cheaper to just buy one that has been refurbished.

if there will be more then a few hours between servicing the a/c changing the compressor, and you do not have a A/C manifold and vacuum pump to suck the air and moisture out of the system, in preparation for gas then do not change the dryer let the garage servicing the A/C system change the dryer right before they vacuum it. the dryer has descant inside and it sucks in moisture. you want it as dry as possible so it sucks the moisture out from inside the A/C system when it is running.

another item overlooked is the vacuum motor that shuts down the heater core which is located on the heater core lines in the engine bay near the firewall behind the engine. the vaccum motor rots internally from the coolant and needs to be replaced every so often. the motor shuts down the coolant to the heater core otherwise the heater core will fight with the evaporator core and you will not have cool A/C.

original A/C equipment is now over 40 years old, so usually the system needs more TLC then just the compressor.

 

[Jeff73Mach1]

I still believe that an aftermarket system is the better value for a car that will not be a daily driver nor a show car. It eliminates all the variables and possible parts that you need to worry about. $1500.00 + about 6 hours work and an evacuate and charge and you are done. The downside to an aftermarket system is that some do not operate as the originals were designed and may change vacuum motors out for cable driven microswitches. Pulleys may not route the same and wiring, if not done neatly detracts from the appearance of your engine bay. But the Sanden compressors are good quality parts and the cost savings make it an option I think is worth considering. But then again mine worked the first time out and has continued to work ever since, so my opinion would be quite different from someone who had a bad experience.

R-12 is still available, that is true, but for how long? IIRC it isn't being made anymore and all that is available is what people have on hand.

Prices will continue to climb as availability drops.

 

[jbojo]

Last time I checked R-12 was about $10.00 an ounce. Typical system has 30 to 38 ounces so you are looking at $400 just for the Freon. If you go to R-134 it is recommended that you replace everything when you do, unfortunately that means the evaporator in the heater box too. in addition R-134 does not cool as well as R-12 so the condenser is much larger with a R-134 system, the one I got is nearly double the surface area. I am in the process of getting mine going and my recommendation is to put a pressure switch on the system. It's just a safety switch so that you don't run the compressor if you have a Freon leak and lock the compressor up. It's a $25.00 part that cuts off the clutch if the Freon pressure drops below a certain PSI. When I have it all hooked up I'll post pics of this switch.

If you use R-134 with a R-12 system parts you can expect a loss in cooling efficiency. The right parts for the refrigerate used produces good cooling. Look at the newer cars, they are all using R-134, I have to back off the temp setting even on 100* + days.

 

[jsbcats]

Amer,

I've got mine over at Classic Mustangs of Houston right now getting the Classic Auto Air system put in mine. They are a couple miles west of the 1960/45 intersection. I'll let you know how it turns out. Mine is a complete replacement.

Wes

 

[salhi_aemr]

Thank you Wes, I am pretty close to you close to Highway 6 & Westheimer, we should go to car shows in our ponys? there is one coming up Aug 8th by West Houston Muscle in Katy Mills parking lot, or every Saturday Niftee 50ees

Amer,

I've got mine over at Classic Mustangs of Houston right now getting the Classic Auto Air system put in mine. They are a couple miles west of the 1960/45 intersection. I'll let you know how it turns out. Mine is a complete replacement.

Wes

 

[jsbcats]

Sounds good. I'll be out of town Aug 8 but I have been wanting to get to Niftee 50ees.

 

[salhi_aemr]

Maybe if your car is done before this coming Saturday we can meet @Niftee 50

Sounds good. I'll be out of town Aug 8 but I have been wanting to get to Niftee 50ees.

 

[Carolina_Mountain_Mustangs]

Just by chance I am working on my air in my 73 vert. It had sat for over 20 years but only has 48,000 miles on it. I had pulled the dash out and decided to put a new heater core in since it still had the original. So while I have the box out I took the evaporator core out and pressure checked it using air with it in water, no leaks. I also checked the new heater core and it had a leak and had to get another one.

So I decided to go through the entire system so I pulled everything off, condenser, compressor, dryer, all the lines and I stripped the old paint, blasted some of the brackets and cleaned all the connections with fine steel wool where the o-rings go. New o-ring kit is just a few bucks and you lube them with Mineral oil. Every original o-ring was either cracked or split when I pulled them out so don’t waste your time trying to charge without changing.

I would never change to an aftermarket system that would take the value of your car way down, they are only original once.

I did quite a bit of research on this since I had never got into one always took to dealer to get charged. I discovered a fairly new refrigerant made by Deepfreeze Refrigerants in Canada. It is called Duracool 12a and is said to be better than R-12 or R-134. One 6 oz. can of Duracool 12a replaces 17 oz. or R134 and 19 oz. of R-12. So I ordered one of their kits with refrigerant, hose and gage, filter, thermometer and new connector for system charge. I also ordered their lube for the compressor.

I also have the Ford shop manual for the system and saw no reason why anyone could not do the job. Went to Harbor Freight got the full set of gages and vacuum pump. Everything together was less than the shop wanted to vac the system and charge.

I was offered a couple cases of R-12 by a friend shutting down his shop he said he could not sell the stuff had taken to a couple swap meets and never sold a single can.

I intend to do a complete thread on the forum about this change and how it works. I have not charged the system yet but getting close still have the dash out. I think you should change the compressor clean out the system and fix it.

David

 

[jbojo]

Just some info, I am not trying to say this is good or bad but want to make sure everyone knows the facts. I was contemplating using this too at one time. Duracool is a hydrocarbon based refrigerant and very flammable. Just did some research on this from the EPA site:

3. What is the legal status of hydrocarbon refrigerants such as HC-12a® and DURACOOL®?

It has been illegal since July 13, 1995 to replace CFC-12 with the HC-12a® formulation that was submitted for SNAP review in any refrigeration or A/C application other than industrial process refrigeration. The same prohibition for OZ-12® took effect on April 18, 1994. Because DURACOOL 12a® has the same chemical composition as the HC-12a® formulation that was submitted for SNAP review (i.e., Hydrocarbon Blend B), DURACOOL 12a® is also subject to the same restrictions.

HC-12a®, as reformulated to meet DOT requirements, is not the same as Hydrocarbon Blend B and has not been submitted for SNAP review. OZ Technology is therefore prohibited from marketing this blend as a substitute for any ozone-depleting substance. In addition, any use of this blend as a substitute for CFC-12 or any other ozone-depleting chemical, in industrial process refrigeration or any other refrigeration or A/C end use, is prohibited under the Clean Air Act.

Since HC-12a®, as submitted for SNAP review, is chemically different from HC-12a®, as reformulated to meet DOT requirements, and since it has a different legal status under the Clean Air Act, users of any substance marketed as HC-12a® should be aware of which HC-12a® they have purchased.

Note: Many states prohibit using flammable refrigerants in motor vehicles, regardless of which original refrigerant was used in the vehicle.

4. May hydrocarbon refrigerants be used to replace CFC-12, commonly referred to as "Freon® ," in cars?

No. It is illegal to use hydrocarbon refrigerants like HC-12a® and DURACOOL 12a® as substitutes for CFC-12 in automobile or truck air conditioning under any circumstances.

5. Why is it legal to use hydrocarbon refrigerants as CFC-12 substitutes in industrial process refrigeration, but not elsewhere?


EPA has not yet received data that adequately address the safety issues of hydrocarbon refrigerants in applications other than industrial process refrigeration. Flammability risks depend on the type of refrigeration or air-conditioning system. Industrial process refrigeration, for instance, does not include air conditioning, which pipes refrigerated air directly into occupied areas. Industrial process refrigeration generally refers to complex customized appliances used in the chemical, pharmaceutical, petrochemical and manufacturing industries. Direct risk to human health is reduced in industrial process refrigeration; for example, access to areas near the system is typically restricted. In addition, other regulations exist to protect the safety of industrial workers.

EPA will review any additional material that is submitted under SNAP regarding the safety considerations of using hydrocarbon refrigerants in systems other than industrial process refrigeration.

 

[Jeff73Mach1]

I guess propane is out then? (And yes propane will work in an R12 system and yes it might be a bit hazardous.)

 

[jbojo]

I guess propane is out then? (And yes propane will work in an R12 system and yes it might be a bit hazardous.)

I see that R-12A is a propane/butane blend, might prove interesting if you have a hose rupture in an hot engine compartment.

 

[Carolina_Mountain_Mustangs]

Just some info, I am not trying to say this is good or bad but want to make sure everyone knows the facts. I was contemplating using this too at one time. Duracool is a hydrocarbon based refrigerant and very flammable. Just did some research on this from the EPA site:

3. What is the legal status of hydrocarbon refrigerants such as HC-12a® and DURACOOL®?

It has been illegal since July 13, 1995 to replace CFC-12 with the HC-12a® formulation that was submitted for SNAP review in any refrigeration or A/C application other than industrial process refrigeration. The same prohibition for OZ-12® took effect on April 18, 1994. Because DURACOOL 12a® has the same chemical composition as the HC-12a® formulation that was submitted for SNAP review (i.e., Hydrocarbon Blend B), DURACOOL 12a® is also subject to the same restrictions.

HC-12a®, as reformulated to meet DOT requirements, is not the same as Hydrocarbon Blend B and has not been submitted for SNAP review. OZ Technology is therefore prohibited from marketing this blend as a substitute for any ozone-depleting substance. In addition, any use of this blend as a substitute for CFC-12 or any other ozone-depleting chemical, in industrial process refrigeration or any other refrigeration or A/C end use, is prohibited under the Clean Air Act.

Since HC-12a®, as submitted for SNAP review, is chemically different from HC-12a®, as reformulated to meet DOT requirements, and since it has a different legal status under the Clean Air Act, users of any substance marketed as HC-12a® should be aware of which HC-12a® they have purchased.

Note: Many states prohibit using flammable refrigerants in motor vehicles, regardless of which original refrigerant was used in the vehicle.

4. May hydrocarbon refrigerants be used to replace CFC-12, commonly referred to as "Freon® ," in cars?

No. It is illegal to use hydrocarbon refrigerants like HC-12a® and DURACOOL 12a® as substitutes for CFC-12 in automobile or truck air conditioning under any circumstances.

5. Why is it legal to use hydrocarbon refrigerants as CFC-12 substitutes in industrial process refrigeration, but not elsewhere?


EPA has not yet received data that adequately address the safety issues of hydrocarbon refrigerants in applications other than industrial process refrigeration. Flammability risks depend on the type of refrigeration or air-conditioning system. Industrial process refrigeration, for instance, does not include air conditioning, which pipes refrigerated air directly into occupied areas. Industrial process refrigeration generally refers to complex customized appliances used in the chemical, pharmaceutical, petrochemical and manufacturing industries. Direct risk to human health is reduced in industrial process refrigeration; for example, access to areas near the system is typically restricted. In addition, other regulations exist to protect the safety of industrial workers.

EPA will review any additional material that is submitted under SNAP regarding the safety considerations of using hydrocarbon refrigerants in systems other than industrial process refrigeration.

Yes that information is on the web site. I am not a business so they sent me the refrigerant. Everything that I read about its performance was great. It has passed all environmental testing in Canada the U.S. always drags their feet approving anything.

We all know the R-12 blow up was a hoax also. Freon is a heavy gas and in now way could have ever got to the ozone layer to do anything. There were studies showing that the ozone levels in the 50's was more out of whack before there were hardly any air conditioners and much less refrigeration.

There was probably some politics in both of the situations.

Studies made using the ginkgo tree have shown that carbon gas levels were higher millions of years ago than they are now. That tree has been growing and still lives for over 270 million years so fossils give details of how the air was in history. I guess the flintstones cars didn't have catalytic converters.

Loud exhaust is illegal also but not going to take that off either.

When I work on my car I always try to find something better and this sounds like a great product that will eventually be allowed here. It will be an interesting test to see how cold the air is coming out of the vents.

I am not going to do something that would harm anyone and yes you cannot go to the local shop and get them to install the duracool in your car but you can.

I would see a CNG vehicle as a much more dangerous fire and explosion hazard over a few ounces of duracool. I ran my van with a dual fuel system back about 1975 when gas got scarce. There was enough propane in the 32 gallon tank and 20 gallon gas tank to take out several city blocks if it leaked out.

I still think it is all political when you see all the buses, trucks and about every brand of car has CNG which will one day be in the headlines when a station or vehicle blows.

I have a friend that when he cranks up his monster 66 GTO that is over 500 CI it makes ice on the intake manifold so much gas is getting vaporized. He thought something was wrong the first time he cranked it and called someone at Roush and they just laughed and told him it was acting like an air conditioner due to the volume of air going into the engine.

Some resist change I embrace it. Some things work some don't but if you don't try you will never know.

David

 

[jeff8877]

R-12 can be picked up at swap meets or on ebay for $15-$30 a pound. You need a bit over 2 lbs as I recall. The components needed to rebuild an original system such as dryer, compressor, expansion valve etc can all be picked up reasonably at rockauto

 

[Carolina_Mountain_Mustangs]

R-12 can be picked up at swap meets or on ebay for $15-$30 a pound. You need a bit over 2 lbs as I recall. The components needed to rebuild an original system such as dryer, compressor, expansion valve etc can all be picked up reasonably at rockauto

I can get the R-12 for free but want to try something new. When I got my 73 I pulled the belt off the air first thing to get that extra hp. Now I am old and need to stay cool, lol.

Are you going to post pics of the Mach during the repaint?

David

 

[1973_Mustang_Conv]

Just by chance I am working on my air in my 73 vert. It had sat for over 20 years but only has 48,000 miles on it. I had pulled the dash out and decided to put a new heater core in since it still had the original. So while I have the box out I took the evaporator core out and pressure checked it using air with it in water, no leaks. I also checked the new heater core and it had a leak and had to get another one.

So I decided to go through the entire system so I pulled everything off, condenser, compressor, dryer, all the lines and I stripped the old paint, blasted some of the brackets and cleaned all the connections with fine steel wool where the o-rings go. New o-ring kit is just a few bucks and you lube them with Mineral oil. Every original o-ring was either cracked or split when I pulled them out so don’t waste your time trying to charge without changing.

I would never change to an aftermarket system that would take the value of your car way down, they are only original once.

I did quite a bit of research on this since I had never got into one always took to dealer to get charged. I discovered a fairly new refrigerant made by Deepfreeze Refrigerants in Canada. It is called Duracool 12a and is said to be better than R-12 or R-134. One 6 oz. can of Duracool 12a replaces 17 oz. or R134 and 19 oz. of R-12. So I ordered one of their kits with refrigerant, hose and gage, filter, thermometer and new connector for system charge. I also ordered their lube for the compressor.

I also have the Ford shop manual for the system and saw no reason why anyone could not do the job. Went to Harbor Freight got the full set of gages and vacuum pump. Everything together was less than the shop wanted to vac the system and charge.

I was offered a couple cases of R-12 by a friend shutting down his shop he said he could not sell the stuff had taken to a couple swap meets and never sold a single can.

I intend to do a complete thread on the forum about this change and how it works. I have not charged the system yet but getting close still have the dash out. I think you should change the compressor clean out the system and fix it.

David

David a few months back I wanted to convert my vehicle to the original AC.

Still haven't got there... a friend of mine is helping and wondering hwo to go about about cutting the firewall for the AC Hoses. (Its a non-AC Car) .

Would you mind getting me a picture of the Firewall and Hose connections from the Engine perspective? Need to figure out how to template the holes.

 

[Carolina_Mountain_Mustangs]

Just by chance I am working on my air in my 73 vert. It had sat for over 20 years but only has 48,000 miles on it. I had pulled the dash out and decided to put a new heater core in since it still had the original. So while I have the box out I took the evaporator core out and pressure checked it using air with it in water, no leaks. I also checked the new heater core and it had a leak and had to get another one.

So I decided to go through the entire system so I pulled everything off, condenser, compressor, dryer, all the lines and I stripped the old paint, blasted some of the brackets and cleaned all the connections with fine steel wool where the o-rings go. New o-ring kit is just a few bucks and you lube them with Mineral oil. Every original o-ring was either cracked or split when I pulled them out so don’t waste your time trying to charge without changing.

I would never change to an aftermarket system that would take the value of your car way down, they are only original once.

I did quite a bit of research on this since I had never got into one always took to dealer to get charged. I discovered a fairly new refrigerant made by Deepfreeze Refrigerants in Canada. It is called Duracool 12a and is said to be better than R-12 or R-134. One 6 oz. can of Duracool 12a replaces 17 oz. or R134 and 19 oz. of R-12. So I ordered one of their kits with refrigerant, hose and gage, filter, thermometer and new connector for system charge. I also ordered their lube for the compressor.

I also have the Ford shop manual for the system and saw no reason why anyone could not do the job. Went to Harbor Freight got the full set of gages and vacuum pump. Everything together was less than the shop wanted to vac the system and charge.

I was offered a couple cases of R-12 by a friend shutting down his shop he said he could not sell the stuff had taken to a couple swap meets and never sold a single can.

I intend to do a complete thread on the forum about this change and how it works. I have not charged the system yet but getting close still have the dash out. I think you should change the compressor clean out the system and fix it.

David

David a few months back I wanted to convert my vehicle to the original AC.

Still haven't got there... a friend of mine is helping and wondering hwo to go about about cutting the firewall for the AC Hoses. (Its a non-AC Car) .

Would you mind getting me a picture of the Firewall and Hose connections from the Engine perspective? Need to figure out how to template the holes.

I will see if I cannot put a piece of paper on the firewall and use the bolt holes for the heater box to align and mark the opening for the hoses. I will take some pics from inside and outside. The non air cars have the cowl vents on both sides but air cars only have a cowl vent on the right for the heater / air conditioner so you will need to block left one off. It is easier to go to air than from air to vents. The vented cars have a bubbled sheet metal part in the side cowl to clear part of the heater that an air car does not have. I will PM with info and will mail the template if I cannot scan it. I have a non air car also might compare them.

David

 

[Carolina_Mountain_Mustangs]

Just by chance I am working on my air in my 73 vert. It had sat for over 20 years but only has 48,000 miles on it. I had pulled the dash out and decided to put a new heater core in since it still had the original. So while I have the box out I took the evaporator core out and pressure checked it using air with it in water, no leaks. I also checked the new heater core and it had a leak and had to get another one.

So I decided to go through the entire system so I pulled everything off, condenser, compressor, dryer, all the lines and I stripped the old paint, blasted some of the brackets and cleaned all the connections with fine steel wool where the o-rings go. New o-ring kit is just a few bucks and you lube them with Mineral oil. Every original o-ring was either cracked or split when I pulled them out so don’t waste your time trying to charge without changing.

I would never change to an aftermarket system that would take the value of your car way down, they are only original once.

I did quite a bit of research on this since I had never got into one always took to dealer to get charged. I discovered a fairly new refrigerant made by Deepfreeze Refrigerants in Canada. It is called Duracool 12a and is said to be better than R-12 or R-134. One 6 oz. can of Duracool 12a replaces 17 oz. or R134 and 19 oz. of R-12. So I ordered one of their kits with refrigerant, hose and gage, filter, thermometer and new connector for system charge. I also ordered their lube for the compressor.

I also have the Ford shop manual for the system and saw no reason why anyone could not do the job. Went to Harbor Freight got the full set of gages and vacuum pump. Everything together was less than the shop wanted to vac the system and charge.

I was offered a couple cases of R-12 by a friend shutting down his shop he said he could not sell the stuff had taken to a couple swap meets and never sold a single can.

I intend to do a complete thread on the forum about this change and how it works. I have not charged the system yet but getting close still have the dash out. I think you should change the compressor clean out the system and fix it.

David

David a few months back I wanted to convert my vehicle to the original AC.

Still haven't got there... a friend of mine is helping and wondering hwo to go about about cutting the firewall for the AC Hoses. (Its a non-AC Car) .

Would you mind getting me a picture of the Firewall and Hose connections from the Engine perspective? Need to figure out how to template the holes.

To keep from tangling up the threads I will go start a new one it will have pictures and a template.

David