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Discussion Starter #1
I'm in the process of putting back together what I believe to be factory air on my 63. Ive been breaking down the engine and took the ac system apart (which it was a closed system prior to) and I'm getting close to putting it back together.

Before I broke the system down I tried running it and from what I could tell the compressor was working but no cooling. The canister thats mounted vertically to the passenger side fender (receiver?) is what I am wondering about. My brother knows a good bit about ac but this year he's not sure about. He was asking me to check if there is some kind of bag that sits inside the canister that captures moisture or if its an open cannister. If its an open cannister with no bag I can reuse it he thinks, otherwise I'll need a replacement.

Any ideas on this?
 

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I'm in the process of putting back together what I believe to be factory air on my 63. Ive been breaking down the engine and took the ac system apart (which it was a closed system prior to) and I'm getting close to putting it back together.

Before I broke the system down I tried running it and from what I could tell the compressor was working but no cooling. The canister thats mounted vertically to the passenger side fender (receiver?) is what I am wondering about. My brother knows a good bit about ac but this year he's not sure about. He was asking me to check if there is some kind of bag that sits inside the canister that captures moisture or if its an open cannister. If its an open cannister with no bag I can reuse it he thinks, otherwise I'll need a replacement.

Any ideas on this?
Your receiver/dryer that you are referring to is a sealed unit.Once the system has been opened and exposed to any possible moisture.It must be replaced.And yes, it has a dessicant bag inside.
 

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Keep the original and send it to Classic Air in Florida. They will cut it open and put in new and reweld it for $80. The original is worth alot restored. They did my 66 and it looks great. Cory
 

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Discussion Starter #6
Thanks for the info, I called classic air in tampa and explained where I am with the restore.

Since I have removed the receiver he recommended replacing it or sending mine down to them for $80 to rebuild.

My concern was having it redone getting it back and re install the system, charge it then find that either the compressor or condenser has an issue. Then i would have to disconnect the failing part and have the $80 go down the drain since that would mean having to redo the receiver again.

I asked if there was a way to test the compressor without having to have it connected to the system. He said that getting a drill to spin the front bolt would give enough power to see if there was proper suction and exhaust by placing a thumb over the valve the bigger being the one to test suction. This is a basic and not thorough test obviously but you get an idea if the compressor was working at all.

The condenser as far as i know is fine. Not sure how to test that really. I did have a stem crack on me when trying to remove a hose from it so it will need to be welded back together.

Ill post back in a few weeks with an update.

thanks again!
 

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it will be a good idea to completely tear the system down and clean the following and change the O rings at the following locations....

Thermal expansion valve....
condenser.....
evaporator....
compressor muffler....

hows the compressor and clutch?

system components are often checked individualiy by pressurizing to high pressures,300 psi or so with nitrogen.

if it was a good system before then you may take your chance on the compressor.
 

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Discussion Starter #10
it will be a good idea to completely tear the system down and clean the following and change the O rings at the following locations....

Thermal expansion valve....
condenser.....
evaporator....
compressor muffler....

hows the compressor and clutch?

system components are often checked individualiy by pressurizing to high pressures,300 psi or so with nitrogen.

if it was a good system before then you may take your change on the compressor.
I had my brother take a look under the hood while I cranked it up last year and fiddle with the AC Controls. I heard him say that the clutch was engaging which surprised him. There was even a bubble in the view glass on the receiver. This system may have been good to go before I broke it down to do an engine restore/rebuild. We didnt have any R12 at the time, but now we have found some.

I went today to the only AC place that I can find locally that deals with restorations. I took the broken down system to them to look at and they say that it really needs to be brought in w the vehicle to accurately
test. Since the engine wont be ready for another couple of weeks I told them that I wanted to get what I could reconditioned that made sense before I start putting things back on, especially the condensor. That thing was a pain to get off. Had to remove the grill and even took the bumper off just to have room to work. They said they would charge me $96 to flush the coils out of the condenser w some kind of acid, blast it, and straighten out any fins that need it. So i left it not really knowing if thats reasonable but was wanting to see some kind of progress. If this seems like a bad idea or price to you guys I could stop them since they said it would be a week or so til they could get to it.

Also I mentioned my concern of having Auto Air in Tampa redo the receiver while I am still in test mode which might lead to having to take a part off the system and render the receiver useless again. They said for now they would recommend keeping it as is for the initial testing on the car. Then once everything else checks out pump out the R12 and send the receiver off to have it redone at that time.

They also recommended rebuilding the POA valve and getting a new expansion valve. I am not sure how to get to these parts yet. The POA isnt listed in the Shop Manual but the expansion valve is. Not sure how to remove the expansion valve yet.

If I take off the muffler what do I clean it with, laquer thinner? And where do I get the o rings and where do they go?

Also is the evaporator the same as the reciever?
 

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No POA valve!

There is no low pressure switch either,so the clutch will engage if all the wiring is there.Having the clutch engage is no indication that the system has sufficient pressure like newer cars.

I understand that you want to simply charge the system and see.Are you willing to sacrifice R12 to do this?

At minimum you should change all the O rings in the system!

Also there are alternatives to R12 such as 406A








I had my brother take a look under the hood while I cranked it up last year and fiddle with the AC Controls. I heard him say that the clutch was engaging which surprised him. There was even a bubble in the view glass on the receiver. This system may have been good to go before I broke it down to do an engine restore/rebuild. We didnt have any R12 at the time, but now we have found some.

I went today to the only AC place that I can find locally that deals with restorations. I took the broken down system to them to look at and they say that it really needs to be brought in w the vehicle to accurately
test. Since the engine wont be ready for another couple of weeks I told them that I wanted to get what I could reconditioned that made sense before I start putting things back on, especially the condensor. That thing was a pain to get off. Had to remove the grill and even took the bumper off just to have room to work. They said they would charge me $96 to flush the coils out of the condenser w some kind of acid, blast it, and straighten out any fins that need it. So i left it not really knowing if thats reasonable but was wanting to see some kind of progress. If this seems like a bad idea or price to you guys I could stop them since they said it would be a week or so til they could get to it.

Also I mentioned my concern of having Auto Air in Tampa redo the receiver while I am still in test mode which might lead to having to take a part off the system and render the receiver useless again. They said for now they would recommend keeping it as is for the initial testing on the car. Then once everything else checks out pump out the R12 and send the receiver off to have it redone at that time.

They also recommended rebuilding the POA valve and getting a new expansion valve. I am not sure how to get to these parts yet. The POA isnt listed in the Shop Manual but the expansion valve is. Not sure how to remove the expansion valve yet.

If I take off the muffler what do I clean it with, laquer thinner? And where do I get the o rings and where do they go?

Also is the evaporator the same as the reciever?
 

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The expansion valve is located inside the under dash unit (evaporator).Look inside the driver side ball and that’s it. A brass looking device with a large line in and out. It can be removed in place if you have the right combination of tools. Otherwise it's best to remove the under dash unit from the car, and completely take it apart to get to the valve. Take the valve apart and clean it. Replace the cone shaped screen filter and O rings. Flush out the evaporator with air, water and more air to completely remove any water that may be trapped inside. Do the same with the condenser.

When you remove the rubber hoses, slice them off! Without scratching or marking the fittings inside! If you failed to do this when removing your condenser hoses then you know what you did wrong and why you now have to repair the tube fittings……


O rings?.......

Compressor muffler-2
Expansion valve-----2
Condesnsor----------2
Filter dryer…………2
 

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Discussion Starter #13
The expansion valve is located inside the under dash unit (evaporator).Look inside the driver side ball and that’s it. A brass looking device with a large line in and out. It can be removed in place if you have the right combination of tools. Otherwise it's best to remove the under dash unit from the car, and completely take it apart to get to the valve. Take the valve apart and clean it. Replace the cone shaped screen filter and O rings. Flush out the evaporator with air, water and more air to completely remove any water that may be trapped inside. Do the same with the condenser.

When you remove the rubber hoses, slice them off! Without scratching or marking the fittings inside! If you failed to do this when removing your condenser hoses then you know what you did wrong and why you now have to repair the tube fittings……


O rings?.......

Compressor muffler-2
Expansion valve-----2
Condesnsor----------2
Filter dryer…………2
Thanks Wagonman!

I have removed the hoses brackets and all, and i did end up slicing them off doing my best not to cut into the aluminum fittings. I had one on the condenser crack on me.

heres a few pics
http://s387.photobucket.com/albums/oo320/msgdesign/ac system/

its cracked where the silver meets the black paint.

A few questions

  1. Should I have the cracked fitting welded or have a new fitting created?
  2. Are the o rings that i will need any different than the rubber ones that Ive found in the hardware stores?
  3. Is R406A or hotshot cheaper to test with? Where can you purchase them?
  4. Should I have the receiver redone by Auto Air in Tampa before I put things all back together? Or should I test the system with the bad receiver before since there is a risk of having to redo it an additional time if the system doesnt check out?
 

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Thanks Wagonman!

I have removed the hoses brackets and all, and i did end up slicing them off doing my best not to cut into the aluminum fittings. I had one on the condenser crack on me.

heres a few pics
http://s387.photobucket.com/albums/oo320/msgdesign/ac system/

its cracked where the silver meets the black paint.

A few questions

  1. Should I have the cracked fitting welded or have a new fitting created?
  2. Are the o rings that i will need any different than the rubber ones that Ive found in the hardware stores?
  3. Is R406A or hotshot cheaper to test with? Where can you purchase them?
  4. Should I have the receiver redone by Auto Air in Tampa before I put things all back together? Or should I test the system with the bad receiver before since there is a risk of having to redo it an additional time if the system doesnt check out?

You can have the fiting repaired.By someone qualified.

You can purchase the O rings from a refrigeration supply house or possibly an auto supply house.Dont use cheap hardware store O rings...

Yes, send out and have your receiver/dryer re-done,meanwhile replace all the O rings and clean the TXV(thermal expansion valve) filter screen.If this screen is full of brass or aluminum,it is an idication of compressor failure.If the screen is clean,then your system may have been ok.I dont know the history of the car.was the system running last week? or has been a decade?

Go ahead and use 406A,you will be happy with it! You may need a license to purchase it i'm not sure.You HAVE to have a license to purchase r12!

After you replace all the O rings,clean out the components install new hoses with a new dryer you can check for leaks by pulling a vacuum.Using a micron gauge will give you a better indication of system "tightness" and cleansiness.Most industrial HVAC techs use this method.I applied it to auto use,its a better way to go.If your brother does'nt have a micron gauge then pull the system down to 29-30 in/Hg. and see if the system will hold that vac for an hour or so.This will give you an idea if its somewhat tight.

From this point,charge the system accordingly with 406A and see how it works.......
 

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Do not use water!

Do not use water or air to flush your coils or any part of the air conditiong system!

Air contains water. Water inside of the system combined with oil, refrigerant and heat under pressure over time will create acid and sludge in the system that will cause major problems down the road.

Water is the last thing you want inside of your sealed system.There are coil flushes for cleaning coils and you must use dry nitrogen to blow them through the coils.


When you broke the system down you should have sealed every component to keep out dirt and moisture. If not flush the coils and replace the oil in the compressor.

When you reasemble it with a new/rebuilt reciver dryer you can use dry nitrogen to pressurize the system and let it set 15 minutes. This will let you know if you have any sizable leaks in the system.

You will then need to have a vacuum pump to pull a deep vacuum to remove all air and moisture from the system. After a good vacuum is pulled you may then recharge the system with refrigerant. If a small amount of water is left the bag in your recever dryer will trap and hold it. It can only trap a small amount of water.

Most People will not have a tank of dry nitrogen and a vacuum pump and will have to pay to have this kind of work done. Doing it wrong may cost more in the long run.

I am not an expert at auto A C systems however I have 32 years under my belt doing refrigeration, heating and air conditioning.

Hope this info helps, good luck
EarlyIIs
 

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Discussion Starter #16
thanks Early11's, I'm picking up the condensor today from being redone. They flushed it out w some kind of acid so its not all rusted out in there. Im about to send off the receiver to be redone as well.
 

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Early11's is technically correct and the textbook way of flushing is with a solution and then nitrogen.

BUT....

Water is a bad thing in an A/C system we know.In a completely torn down system water and air can be used as a vehicle to remove debris from the coils of the condensor,evaporator ect.....blowing it out with air is fine to remove excess water.

After system assembly evacuating the system completely removes water and air.this is why we evacuate!

flushing and presurizing with nitrogen is a proffesional way of doing it.



Personally i didnt have a bottle of nitrogen laying around at my house or shop when i did my system.


Do not use water or air to flush your coils or any part of the air conditiong system!

Air contains water. Water inside of the system combined with oil, refrigerant and heat under pressure over time will create acid and sludge in the system that will cause major problems down the road.

Water is the last thing you want inside of your sealed system.There are coil flushes for cleaning coils and you must use dry nitrogen to blow them through the coils.


When you broke the system down you should have sealed every component to keep out dirt and moisture. If not flush the coils and replace the oil in the compressor.

When you reasemble it with a new/rebuilt reciver dryer you can use dry nitrogen to pressurize the system and let it set 15 minutes. This will let you know if you have any sizable leaks in the system.

You will then need to have a vacuum pump to pull a deep vacuum to remove all air and moisture from the system. After a good vacuum is pulled you may then recharge the system with refrigerant. If a small amount of water is left the bag in your recever dryer will trap and hold it. It can only trap a small amount of water.

Most People will not have a tank of dry nitrogen and a vacuum pump and will have to pay to have this kind of work done. Doing it wrong may cost more in the long run.

I am not an expert at auto A C systems however I have 32 years under my belt doing refrigeration, heating and air conditioning.

Hope this info helps, good luck
EarlyIIs
 

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Discussion Starter #18
no nitrogen around my crib neither:)
but for testing if i need some i will seek it out vs running the r12 that i do have just in case there is a leak.
 

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Water in A C system.

Wagon man is right that the vacuum pumps job is to remove the water (and air) from your air conditionig system.

Let me add that the only way to know if you removed all of the water from an air conditoning system with your vacuum pump is if you have a micron gauge to tell how deep of a vacuum you have pulled. If you don't have one you will not know if you have removed all of the water. .

I do not know just how much water the automotive reciver dryers will trap and hold. My service manual shows they have about 10 cubic inches of desiccant inside of them. An 8 cubic inch dryer like I would install on a small refigeration system will trap and hold 115 drops of water at 125 degrees when used with R12. The automotive reciver will run hotter than 125 degrees and most likley hold less.

As you can see it is possible to not get all of the water out with the vacuum pump and your new reciver dryer will trap it and protect the system if the amount of water is not to large.

In my case I already own the vaccuum pump, two nitrogen tanks and a micron guage.

This does make it much easier for me to go by the book.

EarlyIIs
 
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