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Discussion Starter · #1 ·
My '81 305's A/C quit. It's an original CA car, brought to TX by second owner around 2014. I bought El Roy in 2/20. A/C has stopped working. The refrigerant fittings on the accumulator appear to be R134a and the compressor looks newer (I don't think that sticker would be in that good of shape after 41 years). I can't find an A/C decal under the hood. Is it safe to assume this A/C system has been converted from R12? Anything else I should be looking for to verify?

I've never worked on A/C systems before, but one video I watched indicated that you could tell visually when the compressor was on because of the face of the pully would be idle when off, and rotating when on. I don't see anything like that. Is there a visual indicator to know if the compressor is functioning, or could the refrigerant level be too low not allowing the compressor to turn on? I can't hear the compressor kick in and the idle doesn't change, either when turning on the A/C.

I'm leaning towards starting with simply adding refrigerant just to see if low refrigerant is the problem, and then monitor the pressure every month or so to see if I have any leaks. Is this an acceptable way to see if I have any system leaks, or should I vacuum the system first? Anything else I should be doing?

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Those are R134A fittings. The triangular face piece of your pancake compressor in the last picture will spin when the compressor is engaged.

And those are original R12 hoses and not the "barrier" hoses that should be used with the R134A stuff. An R134A molecule is smaller and needs a barrier hose for best leak prevention.

Your receiver-drier might have a sight glass in the top of the can inline tube to see gaseous refrigerant streaming past but only once your compressor is spinning.

Acceptable method of testing??? If you don't pull the air and moisture out with a good vacuum for 30-60 minutes, that air and water won't be good for your system. I'd pull it down to a vacuum and add some, but not a lot of R134A with the UV dye in it to check for leaks.

Whatever you do, don't introduce sealant into your system. If you ever need to go to a professional A/C repair shop, they won't like you very much when you contaminate their recovery machine. And sealant will clog you expansion valve / suction throttling valve / pilot operated absolute valve anyway.

Rick
 

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Discussion Starter · #3 ·
Those are R134A fittings. The triangular face piece of your pancake compressor in the last picture will spin when the compressor is engaged.

And those are original R12 hoses and not the "barrier" hoses that should be used with the R134A stuff. An R134A molecule is smaller and needs a barrier hose for best leak prevention.

Your receiver-drier might have a sight glass in the top of the can inline tube to see gaseous refrigerant streaming past but only once your compressor is spinning.

Acceptable method of testing??? If you don't pull the air and moisture out with a good vacuum for 30-60 minutes, that air and water won't be good for your system. I'd pull it down to a vacuum and add some, but not a lot of R134A with the UV dye in it to check for leaks.

Whatever you do, don't introduce sealant into your system. If you ever need to go to a professional A/C repair shop, they won't like you very much when you contaminate their recovery machine. And sealant will clog you expansion valve / suction throttling valve / pilot operated absolute valve anyway.

Rick
Thanks, Rick. Is it advisable to change/upgrade the hoses? I contacted the previous owner and confirmed he never performed any A/C service since he bought it...8 years ago.
 

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You may want to follow the A/C lines and look for oil which may indicate where it had leaked in the past. The clutch face should be able to be turned when the engine is not running and when the clutch is energized (switch on dash moved/turned to A/C) the whole front clutch assembly will all turn via the belt when the engine is running. The two wire connector on the accumulator is the low pressure switch and can be jumped with a paper clip and the clutch should engage (click) when the dash switch is set to A/C and the front clutch face should not be able to be turned with the engine not running. If the system is low on Freon, its not advisable to bypass the low pressure switch and run the engine since the Freon + oil is what is needed to keep everything lubricated. Hope that helps.
 

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Discussion Starter · #5 ·
You may want to follow the A/C lines and look for oil which may indicate where it had leaked in the past. The clutch face should be able to be turned when the engine is not running and when the clutch is energized (switch on dash moved/turned to A/C) the whole front clutch assembly will all turn via the belt when the engine is running. The two wire connector on the accumulator is the low pressure switch and can be jumped with a paper clip and the clutch should engage (click) when the dash switch is set to A/C and the front clutch face should not be able to be turned with the engine not running. If the system is low on Freon, its not advisable to bypass the low pressure switch and run the engine since the Freon + oil is what is needed to keep everything lubricated. Hope that helps.
Thanks, chris32. I'll run those tests this weekend on the compressor.
 

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The brass-colored hose connectors look like the system has be reconfigured to R134A. You are correct, that if the refrigerant levels are low, the low pressure switch will not allow the compressor clutch to engage and result in burning out the compressor.If you are not able and willing to do repairs, your two options are: (1) attempt to recharge the system yourself and see if the added refrigerant will result in the clutch engaging and (2) taking your Elky to an AC shop for a recharge. The AC shop will likely give you an assessment of what additional work is necessary. Very likely, if the compressor is ok, they will recommend replacement of the orifice filter, receiver/dryer, and, possibly, the condenser (in front of the radiator).

Just be aware that the shop will try to sell you the whole package which will be a pretty hefty cost!
 

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Good info here. I echo Handyman, but I don't think it is a sales pitch. The AC system relies on many components and shop labor is expensive. You stated the AC system stopped working. There is a reason for this. Leaks are the most common cause. Since the system is empty of freon you do not need to purchase an expensive evacuation storage system or take it to the shop to safely discharge the system. You can certainly do this yourself if you have the time and patience. You will need a vaccum pump $85 and AC charging gauge set $60 from Harbor freight and likely 24 oz of R134a.

If you want this done right and have very high chances of success then you should replace the hoses, drier and condenser. You need to trigger the compressor on to make sure it works. You can run it for 10 seconds without problems. If it does not work then you need to replace the compressor too.

The best online video I found is this one. It gives you all the details you need to vacuum and recharge the system after you change the components.

You also mentioned that you were willing to charge it and monitor the leaks. As others stated, the compressor will not turn on if the freon pressure is low. This is the function of that safety switch. A cheap way to charge the system is to buy the cans with R134 hose connector attached. Add the freon and it may kick on the AC system and work. However, this is very risky on a very old system that was not working for an unknown amount of time. It will likely leak freon into the atmosphere which is bad. However, there is a small chance it will work and not leak. Odds are low.

The better option here if you commit to doing the work yourself is to buy the vacuum pump and gauges. Then you can pull vacuum and hold it in the system to see if it leaks. It likely will. Then you can proceed with replacing parts as your budget fits and keep checking the vacuum. No risk to the environment and if you are on a budget you can select the parts to replace one at a time. Test compressor first to make sure it works then the order of replacing parts should be Drier and Condensor first, then the hoses.

Once you find that you can hold a vacuum for one hour or overnight (better test) then you can safely add oil and freon and the chances of leaks are very low. You need to add the correct amount of freon and typoe of oil. Hopefully this is stated on the tag. If not then you need to reasearch your compressor model to find out the type of oil and the amount it needs. There are a ton of oils so this can be tricky and hard to find. I like to use the oil with dye so if leaks occur you can quickly pinpoint the location of the small leak with a UV light.

Hope this helps.

Cheers,
Scott
 
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Discussion Starter · #8 ·
The brass-colored hose connectors look like the system has be reconfigured to R134A. You are correct, that if the refrigerant levels are low, the low pressure switch will not allow the compressor clutch to engage and result in burning out the compressor.If you are not able and willing to do repairs, your two options are: (1) attempt to recharge the system yourself and see if the added refrigerant will result in the clutch engaging and (2) taking your Elky to an AC shop for a recharge. The AC shop will likely give you an assessment of what additional work is necessary. Very likely, if the compressor is ok, they will recommend replacement of the orifice filter, receiver/dryer, and, possibly, the condenser (in front of the radiator).

Just be aware that the shop will try to sell you the whole package which will be a pretty hefty cost!
Thanks, 57 Handyman. If I understand correctly, the receiver/dryer has dessicant in it which should be replaced. Is there a way to test the condenser to see if it needs replacing?
 

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Discussion Starter · #9 ·
Good info here. I echo Handyman, but I don't think it is a sales pitch. The AC system relies on many components and shop labor is expensive. You stated the AC system stopped working. There is a reason for this. Leaks are the most common cause. Since the system is empty of freon you do not need to purchase an expensive evacuation storage system or take it to the shop to safely discharge the system. You can certainly do this yourself if you have the time and patience. You will need a vaccum pump $85 and AC charging gauge set $60 from Harbor freight and likely 24 oz of R134a.

If you want this done right and have very high chances of success then you should replace the hoses, drier and condenser. You need to trigger the compressor on to make sure it works. You can run it for 10 seconds without problems. If it does not work then you need to replace the compressor too.

The best online video I found is this one. It gives you all the details you need to vacuum and recharge the system after you change the components.

You also mentioned that you were willing to charge it and monitor the leaks. As others stated, the compressor will not turn on if the freon pressure is low. This is the function of that safety switch. A cheap way to charge the system is to buy the cans with R134 hose connector attached. Add the freon and it may kick on the AC system and work. However, this is very risky on a very old system that was not working for an unknown amount of time. It will likely leak freon into the atmosphere which is bad. However, there is a small chance it will work and not leak. Odds are low.

The better option here if you commit to doing the work yourself is to buy the vacuum pump and gauges. Then you can pull vacuum and hold it in the system to see if it leaks. It likely will. Then you can proceed with replacing parts as your budget fits and keep checking the vacuum. No risk to the environment and if you are on a budget you can select the parts to replace one at a time. Test compressor first to make sure it works then the order of replacing parts should be Drier and Condensor first, then the hoses.

Once you find that you can hold a vacuum for one hour or overnight (better test) then you can safely add oil and freon and the chances of leaks are very low. You need to add the correct amount of freon and typoe of oil. Hopefully this is stated on the tag. If not then you need to reasearch your compressor model to find out the type of oil and the amount it needs. There are a ton of oils so this can be tricky and hard to find. I like to use the oil with dye so if leaks occur you can quickly pinpoint the location of the small leak with a UV light.

Hope this helps.

Cheers,
Scott
Thanks, Scott. I'll check the compressor this weekend.
 

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"Is there a way to test the condenser to see if it needs replacing?" vacuum test see if the system holds a vacuum, look for oil on the unit, try adding dye in the Freon and look for the dye, use a Freon leak detector.
 

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One of the most common places to leak is the condenser as it's exposed to everything from the road. Bad O rings is another. Buying a kit to do a recharge yourself isn't a bad idea. I found a nice gauge set at a swap meet and put on an adaptor to use the small cans. There are basically two ways to look for leaks. One is a dye kit with UV light so you can see leaking dye clearly. The other is a halogen leak detector meter. I picked up a Snap On one cheap at a swap and it helped me more than once. The meter has a probe you hold to various places on the system and when it starts singing, you know that's a leak. The dye kit is the cheapest way to go and is a reliable way to find leaks. If you put a gauge on it and see that you do have adequate pressure, then the issue is elsewhere for another reason such a clog or non operating clutch or compressor issue.
 

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Discussion Starter · #13 ·
One of the most common places to leak is the condenser as it's exposed to everything from the road. Bad O rings is another. Buying a kit to do a recharge yourself isn't a bad idea. I found a nice gauge set at a swap meet and put on an adaptor to use the small cans. There are basically two ways to look for leaks. One is a dye kit with UV light so you can see leaking dye clearly. The other is a halogen leak detector meter. I picked up a Snap On one cheap at a swap and it helped me more than once. The meter has a probe you hold to various places on the system and when it starts singing, you know that's a leak. The dye kit is the cheapest way to go and is a reliable way to find leaks. If you put a gauge on it and see that you do have adequate pressure, then the issue is elsewhere for another reason such a clog or non operating clutch or compressor issue.
Thank you!
 

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If you've never done any a/c work you would be smart to get a qualified person to do it for you. The system has to be vacuumed and you need a good set of gauges, etc..Yep you can get rooked by the wrong tech, but do some research and you can find some very honest qualified techs to work with.
 

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Thanks, 57 Handyman. If I understand correctly, the receiver/dryer has dessicant in it which should be replaced. Is there a way to test the condenser to see if it needs replacing?
not really. it is a visual inspection to look for signs of fin damage and leaking. if the condenser appears to be 40 years old you should replace it. it is a disposable part like the drier. vacuum test will indicate a leak but you cannot use that test to determine where the leak is. dye test helps locate leak but you have to pressure charge the system to use the dye. so visual inspection is really the best method. the other important issue to address is that even if the condenser does not leak and looks ok, it can have internal clogs like a radiator. so it may not leak but will not perform well and the ac system will have high pressures and not blow cold. then you have to start all over and not you have to evacuate a fully charged system which requires a shop or expensive evac system to do it right. if in doubt replace it. not expensive and consider it disposable.
 
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Discussion Starter · #16 ·
If you've never done any a/c work you would be smart to get a qualified person to do it for you. The system has to be vacuumed and you need a good set of gauges, etc..Yep you can get rooked by the wrong tech, but do some research and you can find some very honest qualified techs to work with.
Thanks, Wayne. I'm leaning towards having a mechanic do the work, so I'm trying to get educated and check a few things myself so I can at least have an intelligent dialogue with the mechanic.
 

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Discussion Starter · #17 ·
not really. it is a visual inspection to look for signs of fin damage and leaking. if the condenser appears to be 40 years old you should replace it. it is a disposable part like the drier. vacuum test will indicate a leak but you cannot use that test to determine where the leak is. dye test helps locate leak but you have to pressure charge the system to use the dye. so visual inspection is really the best method. the other important issue to address is that even if the condenser does not leak and looks ok, it can have internal clogs like a radiator. so it may not leak but will not perform well and the ac system will have high pressures and not blow cold. then you have to start all over and not you have to evacuate a fully charged system which requires a shop or expensive evac system to do it right. if in doubt replace it. not expensive and consider it disposable.
Thanks, again, Scott.
 

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Elroy81, being educated and learning is a good attitude to have, especially in this hobby and when dealing with an area that you are not familiar with. While there are some unscrupulous people in every business, there are also honorable owners who don't take advantage of someone due to their lack of knowledge. Unfortunately, this happens all the time. As the saying goes...an educated consumer is a good customer!

Just know, there is so much information available online so don't stop learning.
 

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Discussion Starter · #19 ·
not really. it is a visual inspection to look for signs of fin damage and leaking. if the condenser appears to be 40 years old you should replace it. it is a disposable part like the drier. vacuum test will indicate a leak but you cannot use that test to determine where the leak is. dye test helps locate leak but you have to pressure charge the system to use the dye. so visual inspection is really the best method. the other important issue to address is that even if the condenser does not leak and looks ok, it can have internal clogs like a radiator. so it may not leak but will not perform well and the ac system will have high pressures and not blow cold. then you have to start all over and not you have to evacuate a fully charged system which requires a shop or expensive evac system to do it right. if in doubt replace it. not expensive and consider it disposable.
Thanks, again, Scott.
 
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