Howdy folks. Finally got new tranny fluid level correct with it warmed up to proper level and it shifts nicely! Now on to the next project which is the a/c. Blower fan works perfect but no cold air. I read an earlier thread about the fact that you can not get R-12 anymore and the replacement is R-134a but there has to be a modification done in order to use R-134a. 93celicaconv mentioned that if a modification had been done that there would be different connecting fittings and a sticker stating that the modification had been done before I got this car. I checked to see if the clutch kicked in when the a/c button is pressed but nothing and I checked the window on the receiver next to the high pressure charging valve and it was clear, I didn’t see any freon passing through. I thought of checking for fuses exclusive to the a/c compressor just not sure where to look. My thoughts are to do the modification so I can use R-134a but I don’t know how. I have checked around locally and none of the auto repair shops will do the modification and something about having to drain the old R-12 oils from the lines. I would appreciate any input on this subject, thank you.
Toyota777
Howdy folks. Finally got new tranny fluid level correct with it warmed up to proper level and it shifts nicely! Now on to the next project which is the a/c. Blower fan works perfect but no cold air. I read an earlier thread about the fact that you can not get R-12 anymore and the replacement is R-134a but there has to be a modification done in order to use R-134a. 93celicaconv mentioned that if a modification had been done that there would be different connecting fittings and a sticker stating that the modification had been done before I got this car. I checked to see if the clutch kicked in when the a/c button is pressed but nothing and I checked the window on the receiver next to the high pressure charging valve and it was clear, I didn’t see any freon passing through. I thought of checking for fuses exclusive to the a/c compressor just not sure where to look. My thoughts are to do the modification so I can use R-134a but I don’t know how. I have checked around locally and none of the auto repair shops will do the modification and something about having to drain the old R-12 oils from the lines. I would appreciate any input on this subject, thank you.
R-12 conversion to R-134a
Howdy folks. Finally got new tranny fluid level correct with it warmed up to proper level and it shifts nicely! Now on to the next project which is the a/c. Blower fan works perfect but no cold air. I read an earlier thread about the fact that you can not get R-12 anymore and the replacement is R-134a but there has to be a modification done in order to use R-134a. 93celicaconv mentioned that if a modification had been done that there would be different connecting fittings and a sticker stating that the modification had been done before I got this car. I checked to see if the clutch kicked in when the a/c button is pressed but nothing and I checked the window on the receiver next to the high pressure charging valve and it was clear, I didn’t see any freon passing through. I thought of checking for fuses exclusive to the a/c compressor just not sure where to look. My thoughts are to do the modification so I can use R-134a but I don’t know how. I have checked around locally and none of the auto repair shops will do the modification and something about having to drain the old R-12 oils from the lines. I would appreciate any input on this subject, thank you.
I won't go very deep at this point. But, you might want to depress the Schroeder valve (shown in your picture) to see if you have any pressure in the line. If none, the first thing you have to assume is that you have a leak somewhere. You have to identify where the leak(s) is/are and fix that first.
Then, you have to determine if you want to go low cost or go by the book. There are some that say the low cost is just as good as the book conversion. In my book, it is not. Low cost is you leave the old mineral oil in and just add some PAG oil. Book process is to flush out all the old mineral oil and then add PAG oil. Then, with a micron-level vacuum pump, you pull down the system in vacuum to remove all non-condensible air and water vapor. Then leave it sit overnight and see if the vacuum level changes next day - if it does not, the system is sealed and ready for a fill. If it changes, you still have a leak to attend to. WIth the proper oil in there, you add enough R134a per the stated system capacity.
Just realize that a Japanese designed vehicle using R12 is not overdesigned at all. Because R134a is not as efficient, you will loose about 20% of it's original effectiveness. R12 is still available - you can check sellers on eBay - it may be expensive, but likely not as expensive as a conversion. Then the low cost fix and the book fix are the same - you don't need to worry about the oil (unless a fix for a leak involves replacing the compressor, condenser, evaporator, and/or receiver/dryer).
Then, you have to determine if you want to go low cost or go by the book. There are some that say the low cost is just as good as the book conversion. In my book, it is not. Low cost is you leave the old mineral oil in and just add some PAG oil. Book process is to flush out all the old mineral oil and then add PAG oil. Then, with a micron-level vacuum pump, you pull down the system in vacuum to remove all non-condensible air and water vapor. Then leave it sit overnight and see if the vacuum level changes next day - if it does not, the system is sealed and ready for a fill. If it changes, you still have a leak to attend to. WIth the proper oil in there, you add enough R134a per the stated system capacity.
Just realize that a Japanese designed vehicle using R12 is not overdesigned at all. Because R134a is not as efficient, you will loose about 20% of it's original effectiveness. R12 is still available - you can check sellers on eBay - it may be expensive, but likely not as expensive as a conversion. Then the low cost fix and the book fix are the same - you don't need to worry about the oil (unless a fix for a leak involves replacing the compressor, condenser, evaporator, and/or receiver/dryer).
So I performed the test you spoke of and I did get pressurized air that released when I pressed the Schroeder valve, not a lot but enough to know there was pressure in the line. As for the R-12 on ebay, which one is closest to the original R-12; Arctic Air, Frosty Cool, Envirosafe? I assume I will need a charge hose, fitting, and inline gauge. My son said the guy he bought it from told him that it just needed a charge of freon. I want to keep things as original as possible on this car, not to mention the benefits of the R-12 instead of the R-134a.
Several question there. I'll provide some answers. You need an R12 can tap (if you purchase R12 in the small cans) with a connector hose. You don't need a gauge. That Schroeder valve you show in your picture has a viewing glass just above it (needs to be wiped off/cleaned up to see through it better). As you slowly recharge the system, there will be a lot foaming going on that you can see through that site glass. The moment the foam disappears (while the compressor is still running) is when the system is full.
These kind of kits on ebay is all you need to tap the R12 cans and dispense into your car (note, don't use the Schroeder Valve shown in your picture - there is another Schroeder Valve that is in a refrigerant tube just forward of your passenger side strut tower - that is the low pressure line where refrigerant is added. The one in your picture is used when attaching a complete set of gauges to read the high pressure side. Here are some options: Auto Air Conditioner R12 Refrigerant Recharge Leak Kit Freon NOS | eBay and R12 Refrigerant Freon™ Dupont Sercon Igloo Interdynamics Charge Hose & Can Tap / | eBay
As for the R12 itself, the capacity of your system is 25.4 oz. +/- 1.8 oz. I don't see as much old stock R12 on ebay like I used to - I wonder if ebay is restricting the sale of R12?. I would not recommend Frosty Cool, Envirosafe, etc., as those are substitute refrigerants made recently. Arctic Air, Dupont Igloo, Interdynamics, and similar would be good options. Here is one example from ebay: Vintage INTERDYNAMICS 12 AC Refrigerant Can 14 Oz. UNUSED | eBay. In Facebook, there are multiple options - here are a few: Facebook လောဂ်အင်ဝင်ရန် and Facebook လောဂ်အင်ဝင်ရန် and Facebook လောဂ်အင်ဝင်ရန်
The fact you had pressure in your system yet means you hopefully have not had atmospheric air enter the system, so you may be able to avoid drawing down your system with a micron vacuum pump. If you want to be safe, you should pull down your system using a micron vacuum pump for air conditioning systems. There are many auto parts stores that have free rentals of such a pump.
If you get your supplies, let me know before you attempt to add refrigerant - I should be able to help you on the process better in a separate post when you are ready.
These kind of kits on ebay is all you need to tap the R12 cans and dispense into your car (note, don't use the Schroeder Valve shown in your picture - there is another Schroeder Valve that is in a refrigerant tube just forward of your passenger side strut tower - that is the low pressure line where refrigerant is added. The one in your picture is used when attaching a complete set of gauges to read the high pressure side. Here are some options: Auto Air Conditioner R12 Refrigerant Recharge Leak Kit Freon NOS | eBay and R12 Refrigerant Freon™ Dupont Sercon Igloo Interdynamics Charge Hose & Can Tap / | eBay
As for the R12 itself, the capacity of your system is 25.4 oz. +/- 1.8 oz. I don't see as much old stock R12 on ebay like I used to - I wonder if ebay is restricting the sale of R12?. I would not recommend Frosty Cool, Envirosafe, etc., as those are substitute refrigerants made recently. Arctic Air, Dupont Igloo, Interdynamics, and similar would be good options. Here is one example from ebay: Vintage INTERDYNAMICS 12 AC Refrigerant Can 14 Oz. UNUSED | eBay. In Facebook, there are multiple options - here are a few: Facebook လောဂ်အင်ဝင်ရန် and Facebook လောဂ်အင်ဝင်ရန် and Facebook လောဂ်အင်ဝင်ရန်
The fact you had pressure in your system yet means you hopefully have not had atmospheric air enter the system, so you may be able to avoid drawing down your system with a micron vacuum pump. If you want to be safe, you should pull down your system using a micron vacuum pump for air conditioning systems. There are many auto parts stores that have free rentals of such a pump.
If you get your supplies, let me know before you attempt to add refrigerant - I should be able to help you on the process better in a separate post when you are ready.
I checked the local O’reillys and the rental pump is for R-134a only. Here are the items I plan on purchasing, please advise
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I would not get that vacuum pump. A target vacuum on these air conditioning systems is about 500 microns or 29.92 in. of mercury.
Better choices from Harbor Freight would be:
- 2.5 CFM Vacuum Pump
or
- 3 CFM Two Stage Vacuum Pump
These would be the level auto parts stores would have for rentals.
Better choices from Harbor Freight would be:
- 2.5 CFM Vacuum Pump
or
- 3 CFM Two Stage Vacuum Pump
These would be the level auto parts stores would have for rentals.
I have converted many a personal car to 134 including my 91 Celica.
Do not get that vacuum pump. It needs to be connected to a compressor to work, and the compressor has to run a very long time to get low enough vacuum.
Check around with other parts stores to see if they have a normal 2stage vacuum pump to run as it will pull the proper deep vacuum.
Try the local pawn shop for an old r12 set of gauges. Also, they usually have piles of hoses that you could fit to a new guage.
Ideally, you should use a full set of gauges with localized shutoff (near the car). This ensures that
If converting, I have used ac flush and device. Disconnect pipes and flush. Pull the compressor and tip to drain as much oil as you can. Pour in flush and rotate to break up oil, drain repeat. Replace drier/accumulator and o rings that you can reach. Add pag per above to compressor and accumulator. Connect everything and apply vacuum, let sit overnight. Connect new shroeder valve fittings to fit 134 guages. Connect can and open, vacuum will pull Freon in. Shut off can connection. Connect new can (if using small cans) and open again. You'll reach an equilibrium that is enough to stay above the low Freon switch limit. Start car and turn on ac. There are tables to show where high and low pressures should be. These tables account for air temp and humidity levels to fine tune the amount. (Pressure in the system will be higher if the outside temp is higher)
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Do not get that vacuum pump. It needs to be connected to a compressor to work, and the compressor has to run a very long time to get low enough vacuum.
Check around with other parts stores to see if they have a normal 2stage vacuum pump to run as it will pull the proper deep vacuum.
Try the local pawn shop for an old r12 set of gauges. Also, they usually have piles of hoses that you could fit to a new guage.
Ideally, you should use a full set of gauges with localized shutoff (near the car). This ensures that
- you can monitor for problems (hi too high or low too high)
- minimize the dump of Freon and introduction of air/moisture.
If converting, I have used ac flush and device. Disconnect pipes and flush. Pull the compressor and tip to drain as much oil as you can. Pour in flush and rotate to break up oil, drain repeat. Replace drier/accumulator and o rings that you can reach. Add pag per above to compressor and accumulator. Connect everything and apply vacuum, let sit overnight. Connect new shroeder valve fittings to fit 134 guages. Connect can and open, vacuum will pull Freon in. Shut off can connection. Connect new can (if using small cans) and open again. You'll reach an equilibrium that is enough to stay above the low Freon switch limit. Start car and turn on ac. There are tables to show where high and low pressures should be. These tables account for air temp and humidity levels to fine tune the amount. (Pressure in the system will be higher if the outside temp is higher)
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I appreciate everyones input. I feel going forward that converting the celica to 134a might be in my best interest going forward. I know R-12 is becoming very hard to get and I don’t want to run into the issue of not finding it in the future. I am waiting for a quote from a local garage on the conversion because I do not have the equipment or place to do the work. Does anyone have an idea of what a fair quote would be?
Typically 1-2K.
When the boys started driving, we ended up with 6 cars. At 1.5K per AC repair, I figured out that I could acquire all the better tools for the cost of the 1st repair. Made my money back on the next 8 repairs (seal breaks, condensor holes, compressor seizes, etc)
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When the boys started driving, we ended up with 6 cars. At 1.5K per AC repair, I figured out that I could acquire all the better tools for the cost of the 1st repair. Made my money back on the next 8 repairs (seal breaks, condensor holes, compressor seizes, etc)
Sent from my Pixel 5 using Tapatalk
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