R12 convert to r134a of Technology
Recently the owner of a '65 Mustang asked us how to convert his car's original compressor, converting from R12 to R134a refrigerant.Mercedes-Benz 300D TURBO 1987. Converting to 134a. To convert from R12 requires a new receiver/drier (not expensive) and a competent tech who knows about the incompatability of these two refrigerants. Your Nippondenso compressor contains mineral oil which you cannot completely remove by evacuating the system.Oregon. Jul 18, 2016. #4. Lat year, I bought a FZJ80 where the A/C didn't work. It used R12. I decided to convert to R134a. The advantages of R134a is that it is cheap, readily available, and environmentally friendly. I bought a manifold set and a few other specialty tools needed to recharge / convert. I figured that if I got it working, it was ...R134a refrigerant is lighter than R12. To ensure the right charge, you must fill the new system with between 75 and 85% of the factory-set capacity for optimal cooling. To discover the capacity for refrigerant, you want to use the specs for the current system and multiply the R12 charge by 0.9 or 90%. Subtract ¼ or 0.25 pounds from this number.Recharge With R134a. Connect the can of R134a refrigerant to the low-pressure side service port. Open the valve on the can of R134a and allow the refrigerant to flow into the AC system. Once the AC system has been recharged, close the valve on the can of R134a and disconnect it from the service port. Check for leaks.R12 to R134a Convert Adapter : Our low/high side r12 to r134a convert adapter can convert your old 1/4'' SAE or 7/16"-20 UNF R12 R22 charging port for fiting r134a quick charge hose, nice tool for automotive air conditioning refrigerant systems. High Quality : Our r12 to r134a retrofit adapters are made of high quality brass material, with ...R22 to R134a A/c Retrofit Fitting Adapter Kit, R12 R22 to R134a Conversion Adapter Kit for A/c Air Conditioner Refrigerant System Compatible with 1/4 SAE Thread (Gold) $1199. Typical: $12.99. Save 5% with coupon. FREE delivery Fri, May 10 on $35 of items shipped by Amazon. Or fastest delivery Thu, May 9.Oct 4, 2021 · A short video covering tips for retrofitting older A/C systems to R134a. It's not as simple as adding R134a refrigerant. Be sure to use proper fittings and s...R12, the AC works best with R12. If it is still cooling, I would use some gauges to measure the pressures. and add R12 until the pressures read correctly for the ambiant temperature. If the system needed major AC component replacement I would. consider converting to R134 but some articles mention that to.Aug 25, 2017 · To convert R12 to R134a in your system there are only a few small changes you need to make to the system. The compressor that is used in your older R12 system luckily will still work R134a refrigerant and still be just as efficient. The condenser and evaporator are simply heat exchangers so they also do not need to be changed to run a different ...cadillacmike68. A good shop can get an R134a conversion to work just as well as the original R12 system. Here in FL it gets to 95 F + every day and I can get 45 deg F air out of the system after a few minutes. Maybe my ginormous original condenser helps, but it is just as good as when it was using R12.The Dan. You are not allowed to do it yourself. You have to be a certified A/C repairer to do it. The old gas has to be stored in a container and disposed of properly because it is ozone depleting. The R134A gas is toxic to humans. Cost is $200 if you live in brisbane, PM me for details if you wish.R12 to R134a Conversion Kit, R12 to R134a AC Retrofit Fitting Adapter Kit, High/Low Pressure R12 to R134a Retrofit Kit with 1/4'' Female to 7/16"-20 UNF Connection, for Auto A/C Refrigerant System-2. 5.0 out of 5 stars 1. $9.99 $ 9. 99. 6% coupon applied at checkout Save 6% with coupon.So the cost of R-12 is real expensive, think along the lines of a 12 oz can of R-12 is about $80 last time I checked vs a 12 oz can of R-134a going for $19.99 currently. I've seen many cans of R12 on eBay, they're around $30-40 a can, but that stupid license requirement means I have to have a shop recharge it.A/C R134a Refrigerant Retrofit Kit. Part #: TEM 408886. Line: NAPA Temp Products. or 4 interest-free payments of $8.75 with. Qty: Add to Cart.While replacing the condenser is a major step in assuring reasonable performance with R134a, and youre doing everything right, Id hate for you to be disappointed in the conversion not cooling well enough in TX heat. If your replacement condenser is the OE R12 style, it wont work that well for R134a. I did run a successful 134a retrofit (kept OE ...Using the specs for the current system, multiply the R12 charge by 0.9 or 90% to determine the refrigerant capacity. From this number, subtract 1/4, or 0.25 pounds. R134a won't provide the same level of cooling as R12, though. You might find that the system doesn't get as cool even after properly charging it.Type in r12 to r134a conversion in the search box. I got one on Ebay for about $6.00. When you replace the adaptor, be sure to replace the high pressure switch as well as the drier prior to evacuating the system. Perhaps I should start a new thread, let me know if this is off base, thanks.Taking the right travel adapter with you will ensure you're never without — but with so many types, it can be tricky to know what you need. We may be compensated when you click on ...Refrigerant Can Leak Easier. For starters, R12 systems and R134a systems are designed differently to accommodate the gaseous state of each. R134a systems work at higher discharge-side pressures than R12 systems, which could lead to compressor seals leaks. Additionally, since R134a is composed of much smaller molecules, it has a greater chance ...Formula: (R12 Charge Specification x 0.9) – 0.25 lbs. = R134a Charge Level. As an example, let's say the R12 charge specification is listed at 2 lbs. You would do the …Finally, add the new R134a oil, evacuate and recharge with r134a. The total for (most parts) from Lexus was about $800 + about $200 in flush, r134a and misc. The bottom line is to stick with R12 unless you are willing to do the conversion correctly. Hope this helps with your decision. - Kevin.Cost of Converting an R12 to the R134a System. It will generally cost you about $200 to have a mechanic convert an AC system for you. If you want to replace a vehicle's AC system, it will cost between $1,500 and $4,000 with an average cost of $2,750. If you decide to have a professional work on your car, you will have several options for ...When an R-12 system is retrofitted to 134a, the general rule of thumb is that the refrigerant capacity/charge should be reduced to 80-90 % of the original capacity. The original GM spec for these trucks was 56 ounces of R-12. So, if we take 56 ounces of R-12 and multiply it by .85, we get a 134a charge of 48 ounces. But, to answer your question:R134a refrigerant O-rings are of a different composition than those for R12 systems. R-12 O-rings are black in color. R-134a O-rings are blue or green in color. Ester oil charge for lubrication (amount varies by model year). You can also use PAG (Poly Alkylene Glycol) or Castrol Retro Oil for lubricant. R134a refrigerant (amount varies by model ...Supposedly, the 134A has much smaller molecules than the R12. So small that the 134A will bleed through the lines that came with the R12. At this point, I know of 7 changeovers from R12 to 134A with no bleed through. The oldest is 2 1/2 years and the newest about 7 months. Evacuation is critical though.Frequently bought together. Model 1029471 - Corvette Air Conditioning Conversion Kit, R12 To R134A, Late 1977-1982 - This kit includes a re-manufactured compressor which will operate with R134A Refrigerant, a drier, an evaporator orifice and the oil, seals, fittings and adapters. Allows Easy Conversion Includes All Conversion Parts.The key to the conversion is to find/fix any leaks that caused the R12 to leak out, R134A is smaller and will leak from a very small R12 leak. Actually, keeping the old condenser will yield a better cooling effect over a 134A condenser. New drier, new compressor and orifice tube a good flush, good vacuum and recharge it should be trouble free.Buy R12 to R134a Conversion Kit, 1Pair R12 to R134a Convert Adapters, R12 to R134A AC Retrofit Fitting Adapter Kit, R12 to R134a Adapter Fittings, Fits for Car AC Air Conditioner Refrigerant System: Air Conditioning Line Repair Tools - Amazon.com FREE DELIVERY possible on eligible purchasesConverting from r12 to r134a. i have a 1987 f150 i have to convert the ac to r134a. I have the new fittings but it says that i have to change the receiver drier because it has to have a different type of desiccant in it i called technical support for 4 seasons to see whats in theirs and i was told that from factory the 1987s have a receiver ...Features & Benefits. Warranty: Standard : Limited Lifetime. Download. Includes all parts needed for retrofitting. More cost effective than R12. Converting to R134 is less harmful for the environment. Compatible with all newer compressions. Compatible with all newer compressions.R12 to R134a Conversion Kit, 1Pair R12 to R134a Convert Adapters, R12 to R134A AC Retrofit Fitting Adapter Kit, R12 to R134a Adapter Fittings, Fits for Car AC Air Conditioner Refrigerant System. 4.3 out of 5 stars. 14. 50+ bought in past month. $9.99 $ 9. 99. Save 3% on 2 select item(s)Buy R12 to R134A AC Fitting Adapter Kit, R12 to R134a Conversion Kit, Quick Coupler Valve A/C Fitting, R12 R22 to R134A High/Low Fitting Port 1/4In SAE Conversion Adapter, Pack of 2: Air Conditioning Line Repair Tools - Amazon.com FREE DELIVERY possible on eligible purchasesYou can MAKE a R134 system work as well as a R12 system but it takes time and a real good A/C tech. When you convert, it helps because you have more of it in the system. I wish there was way to turn the R134 system into a R12 system personally. If you start a thread, be responsible and post the final outcome.R12 to R134a Conversion Kit, R12 to R134a AC Retrofit Fitting Adapter Kit, High/Low Pressure R12 to R134a Retrofit Kit with 1/4'' Female to 7/16"-20 UNF Connection, for Auto A/C Refrigerant System-2. 5.0 out of 5 stars 1. $9.99 $ 9. 99. 6% coupon applied at checkout Save 6% with coupon.The key to the conversion is to find/fix any leaks that caused the R12 to leak out, R134A is smaller and will leak from a very small R12 leak. Actually, keeping the old condenser will yield a better cooling effect over a 134A condenser. New drier, new compressor and orifice tube a good flush, good vacuum and recharge it should be …1. Don't expect 134a to cool as well as R-12 no matter what you do. 2. To give 134a the best shot, buy a 134a expansion valve. 3. Dryers are refrigerant specific. Get one for 134a. 4. You only have to replace seals on fittings you disconnect. 5. There's enough room for straight adaptors, you don't need angle ones. 6. For your hot weather, …Hello friends, I have a question about converting the old R12 system to R134 system for my 91 Volvo 740. I've posted this question in the 740's section but didn. FAQ; Active Topics; ... Converting AC system from R12 to R134a. Help, Advice, Owners' Discussion and DIY Tutorials on all Volvo's "mid era" rear wheel drive Volvos. 1975 - 1993 240R12 To R134a Conversion Kit, with Dust Cap, R12 R22 R502 to R134A Fast Quick Conversion Adapter Switch, Adapter Valve 1/4Inch SAE Low Side Port Adapter, R134A Quick Coupler Interface, and Core Valve. 4.0 out of 5 stars. 60. $6.99 $ 6. 99. FREE delivery Tue, May 21 on $35 of items shipped by Amazon.One key to the use of R-134a is the amount to use. At a given temperature, R-134a will have a higher pressure than R-12. Therefore, you must use LESS R-134a in your system than you would R-12. The formula is this: R-12 amount x 90% - 1/4 lb. = R-134a amount. In the F-body system, 48 ounces of R-12 are used (3 pounds).R134a requires larger compressors and larger heat exchangers than R12, so performing a conversion while retaining the factory R12 compressor/heat exchanger means you can only fill the system to roughly 80% capacity. For example, if your system originally had 34 oz of R12, then your newly converted R134a system will only have 27 oz (34 x .80 ...The old R-12 system took 4.25 lbs , so I'm going to start with 3.75 lbs of R-134A But what about the refrigerant oil? My new 134A compressor came with a 3 oz. charge. My original service manual states that the factory compressor should have 10.5 oz of oil.Changing the desiccant to XH-7 is usually recommended if an R-12 system is converted to R-134a. The desiccant should also be replaced if a blend contains R-22 because R-22 is not compatible with XH-5 or XH-7 desiccant. The recommended desiccant in this case would be XH-9.R12 is hard to find and very expensive too. I would appreciate any inputs and info. Thanks! R12 is not much more than r134. Look on eBay. It's about 40$ a pound. You need about 2 lbs. the converting to r134 the right way will cost you a whole lot more. Just change the compressor, check for leaks, and charge with r12. The cost of converting an R12 to the R134a system will vary The old R-12 system took 4.25 lbs , so I'm going to start One key to the use of R-134a is the amount to use. At
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Sep 22, 2014 · 09:05 AM. 06:21 PM. 1987 - 1996 F150 & Larger F-Series Trucks - 1990 F150 AC 134a Conversion - I am a new member that is converting my 1991 F150 AC system from R12 to 134A. I changed out everything, but the evaporator core, which I flushed. I put a 134A type clutch cycling/pressure switch in.The R-12 system in my '92 Corvette with R12 in it doesn't do any better than that. I actually have a ton of R-12 around in small and large containers that I have had for years. But, when my '92 R-12 system gives out, I am doing a "major" conversion to R134a -- meaning, I am putting the condenser, evaporator, compressor, and all the a/c lines ...Easy to use kit, includes everything needed to recharge an automotive A/C system or retrofit from R-12 to R-134a. Includes three cans of High Mileage R-134a with Oil and How-To CD. Comes with reusable trigger dispenser with built-in gauge and temperature dial indicator. Includes retrofit valves needed to convert the high and low-pressure ports ...Remove R12 in the system and replace liq. line filter drier. Evacuate the system, topped with correct amount of POE oil and charge with R134a. The Saint has given you the proper procedure for converting a system from R-12 to R134A in a sealed system. Yours are belt driven, big difference.One of the best ways to make sure you can play all of your TV shows and movies on any device, anywhere you go, is by making sure they're all in the same format and have the same co...CORRECT CHARGE AMOUNT - The typical 134a charge of a factory R12 system is 70-80% of the original R12 charge amount. NOTE - Ignore the sight-glass. A properly charged 134a system will likely show bubbles in the sight-glass. If your sight-glass is clear with a 134a charge, the system is significantly overcharged.A/C Guy. 80 posts · Joined 2011. #15 · Nov 9, 2012. Since the manual says to use vacuum pump oil, the machine can be used for r134a. Drain most of the oil by tipping the unit upside down and upright then upside down repeatedly. Then fill with synthetic oil and you will get many happy miles out of it. Like.Buy Fourtry R12 to R134a Conversion Fitting Adapter Kit - R12 to R134a Retrofit Kit with High/Low Side Fitting, Conversion Kit with Fitting Port 1/4" to 7/16" Fit for Car A/C Air Conditioner Refrigerant: Air Conditioning Line Repair Tools - Amazon.com FREE DELIVERY possible on eligible purchasesSimplifies conversion from the old R12 to newer 134a. (For more information on converting to 134a, click here.) Reduce horsepower draw. Reduce weight. NOTE: 1 . This kit will only work on vehicles that have a small block Chevy V8 with compressor mounted on the drivers side (left) of the vehicle and stock v belt setup.Classic Auto Air is your source for Model Specific A/C kits for 80's & older Ford, GM, Mopar, Porsche, Custom Street Rods & more.R12 to R134A Adapter, R12 R22 to R134A High/Low Fitting Port Retrofit 1/4'' to 7/16"-20 UNF Conversion Adapter, Fits for AC Air Conditioner Refrigerant 4.1 out of 5 stars 614 1 offer from $9.49Apologies for the delay in replying but I couldn't find this immediately. I don't know if the kits are still available but this covers the procedure for cars from 1975 to 1990. For the 1991 on model the instructions are slightly different. Converting AC from R12 to R134 240 1975 to 1990.pdf. (3.37 MiB) Downloaded 1493 times.The conversion of R12 to R134a refrigerant is according to a formula. Applying this formula will convert the value of the original R12 charge to the R134a charge. You can begin the formula in pounds by multiplying the R12 charge value by .75. When the scales are in point story .25 or .5 increments, it is adjusted to the highest quality.Keep the original mineral oil refrigeration oil and run a b*u*s*t*a*r*d refrigerant like Freeze 12, or get all the mineral oil you can out of the system and install POE oil and R-134A, or COMPLETELY flush the system of mineral oil, replace the compressor and dryer, and install PAG oil and R-134A. The BEST and Deere-approved method is the latter ...R134a is the most commonly used refrigerant to convert automotive air conditioning away from the destructive R12. It's possible to convert from R12 to R134a without replacing the system's components, so when R134a was brought out, it seems to be a good match to many automotive air conditioning issues.09:05 AM. 06:21 PM. 1987 - 1996 F150 & Larger F-Series Trucks - 1990 F150 AC 134a Conversion - I am a new member that is converting my 1991 F150 AC system from R12 to 134A. I changed out everything, but the evaporator core, which I flushed. I put a 134A type clutch cycling/pressure switch in.R12, the AC works best with R12. If it is still cooling, I would use some gauges to measure the pressures. and add R12 until the pressures read correctly for the ambiant temperature. If the system needed major AC component replacement I would. consider converting to R134 but some articles mention that to.The oil used in R12 and R134a are different and not compatible. So the steps involved are cleaning out the old oil, replacing all the O-rings, replacing the dryer, replacing the expansion valve, and converting the high and low side connectors from Schrader to quick connect valves. I bought a manifold set and A/C system flush kit off Amazon ...This 1968-1990 Corvette air condition conversion kit includes everything needed to convert your R12 air condition system to the more environmentally friendly R134a refrigerant. The kit includes new service port adapters, 12oz Ester oil and an assortment of R134a compatible O-rings and lube. Note: Zip recommends replacing the drier/accumulator ...Buy R12 to R134A AC Retrofit Fitting Adapter Kit, R12 R22 to R134A High/Low Fitting Port Retrofit 1/4’’ to 7/16"-20 UNF Conversion Adapter, Fits for AC Air Conditioner (A/C Adapter Valve Core Kit): Air Conditioning Line Repair Tools - Amazon.com FREE DELIVERY possible on eligible purchases1983-1993 A/C Conversion Kits: http://latemodelres.to/ACconversionKits_YouTube_____How To Charge Your Must...I'm converting from R12 to R134a. For R12, our cars take 33oz of R12 & 5oz of mineral oil. Now that I'll be converting to R134a, what's the correct capacity? I've read a few threads on this topic and I only found a single post saying you can't use 33oz of R134a.Santech Adapter - R12/R134a Air Conditioning Adapter Fitting Shop All Santech. Santech121101. Part # MT1617. SKU # 121101. Year Warranty. In-Store Pickup. Select Store. for pickup availability. Home Delivery Get it by. June 1. Same Day Delivery Not available. In stock | Estimated delivery June 1. ADD TO CART. PRODUCT SPECIFICATIONS. Warranty: 1 ...Buy Yaocom R12 to R134a Ac Fitting Adapter Kit, R12 to R134a Conversion Ac Retrofit Fitting Adapter Quick Coupler Valve A/c 90° Fitting, High Low Side Retrofit Fits for Car Ac Air Conditioner Refrigerant: Air Conditioning Line Repair Tools - Amazon.com FREE DELIVERY possible on eligible purchasesThe proper way is to have the proper equipment. First, you have to evacuate the system of R12. Second, have the proper fittings for the low side and high side. Remove the old R12 fittings and install the new R134 fittings. Third, add the same amount of R134 oil that was evacuated from the R12 system.Steps To Convert R-12 to R-134a. Take the vehicle to a repair shop licensed for A/C work that can evacuate the system of R-12 and recover it properly. Using an A/C flush kit, flush the evaporator and condenser to remove any remaining mineral oil in the system. Empty oil from the compressor and flush oil from high-pressure and suction lines.2 Reasons the 134A conversions will never work correctly. the gas filament inside the expansion valve is set to an R12 temperature. So original expansion valves will never work properly with 134A temperature. At night you might get a slight cool moment. Secondly, the design of the condenser is a "tube and Fin" design.A/C conversion. It's hard to do a detailed step by step on this. The biggest problem is the difference in the oils used in R12. and R134a systems. It's generally accepted that one cannot effectively remove. all the R12 mineral oil from a compressor that has run it. Same goes with the receiver/dryer.As for the R134 oil, 8 ounces of ester or PAG 150 will be fiThe cost of R12 is around $400 / lb in my area
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1973 Mach 1 a/c conversion from r12 a to r134a. My car still has the original a/c system and components and I'm wanting to get it converted to the new type freon. As far as I know everything is there and works including the compressor. I have been told that all I need to do is install new fittings on the refrigerant lines and install an inline ...R12 to R134a Conversion Kit, R12 to R134a AC Retrofit Fitting Adapter Kit, High/Low Pressure R12 to R134a Retrofit Kit with 1/4'' Female to 7/16"-20 UNF Connection, for Auto A/C Refrigerant System-2. 4.6 out of 5 stars. 14. $9.99 $ 9. 99. Buy 3, save 5%. FREE delivery Mon, Mar 18 on $35 of items shipped by Amazon.The most important thing when converting to 134, is that you MUST make sure to put the system into a complete vacuum (30"Hg) to burn off the moisture and residue from the old r-12. I suggest finding a shop that won't charge too much to reclaim the R-12 from the system and suck it down into a vacuum. Install kits can be purchased at aftermarket ...[PACKING] These Low/High side retrofits/adapters/fittings will convert your old 1/4" SAE or 7/16"-20 UNF R12 R22 charging port and make it accept the R134a quick disconnect hose.Retrofitting AC systems is something that has been done for many years now. In 1996 systems were switched over to R134a from R12 refrigerant. R12 refrigerant...2 Reasons the 134A conversions will never work correctly. the gas filament inside the expansion valve is set to an R12 temperature. So original expansion valves will never work properly with 134A temperature. At night you might get a slight cool moment. Secondly, the design of the condenser is a "tube and Fin" design.Apr 27, 2015 · Location: Youngstown Ohio. Posted April 27, 2015. It's also worth noting that the 134a system runs at a higher pressure than a r12 system and in some cases the hoses need to be changed with barrier hose . You will only need to put 70-80% of the recommended r12 amount with 134 a .Compatible with all newer compressions. Murray retrofit kits and components are designed to upgrade R12 A/C systems to R134a and are compatible with nearly all compressor types. Retrofit adapters are compatible with R134a refrigerant and charging manifolds, and are precision-manufactured for application-specific fit and accuracy.The oil used in R12 and R134a are different and not compatible. So the steps involved are cleaning out the old oil, replacing all the O-rings, replacing the dryer, replacing the expansion valve, and converting the high and low side connectors from Schrader to quick connect valves. I bought a manifold set and A/C system flush kit off Amazon ...Formula: (R12 Charge Specification x 0.9) – 0.25 lbs. = R134a Charge Level. As an example, let's say the R12 charge specification is listed at 2 lbs. You would do the following: Example: (2 lbs. x 0.9) – 0.25 lbs. = 1.55 lbs. This indicates that an R12 charge level of 2 lbs. converts to an R134a charge level of 1.55 lbs.I converted my Audi GT to R134a when I modernized it with a Sanden compressor vs the old York style (still R12 components). The only parts I replaced were O-rings and hoses, because I needed custom fittings to route the latter. The system worked BETTER than it had with R12.Installation video:Rspeed Miata R12 to R134 Air Conditioning A/C Conversion Retrofit Kit for 1990-93 MiataRspeed.netPart#: NAB-71450Product link: https://www...R12 to R134a Conversion Kit, 2 Pair R12 to R134a Convert Adapters, R12 to R134A AC Retrofit Fitting Adapter Kit, R12 to R134a Adapter Fittings, Fits for Car AC Air Conditioner Refrigerant System. 4.5 out of 5 stars. 12. $16.99 $ 16. 99. FREE delivery Mon, Mar 25 on $35 of items shipped by Amazon.Classic Auto Air is your source for Model Specific A/C kits for 80's & older Ford, GM, Mopar, Porsche, Custom Street Rods & more.Vintage Air 18865 Goll St. San Antonio, TX 78266 P. 1-800-862-6658 F. 210-654-3113Apr 2, 2011 · 227 posts · Joined 2011. #8 · Apr 3, 2011. Yeah, California just switched from 134a to 134ca, which is the same thing, except instead of the puncture top, they are now self sealing tops, which require a special adapter which costs another $6, then you have an additional $10 core charge for each can, so that the state can reclaim the 8-10% ...A/C Guy. 80 posts · Joined 2011. #15 · Nov 9, 2012. Since the manual says to use vacuum pump oil, the machine can be used for r134a. Drain most of the oil by tipping the unit upside down and upright then upside down repeatedly. Then fill with synthetic oil and you will get many happy miles out of it. Like.R134a systems use less refrigerant and more oil as compared to R12. The receiver/dryer should be replaced. If the new one has a sight glass, it'll be useless after the conversion, and the milky appearance is normal. It's normal for the cooling to be slightly less effective after the conversion.Dean. 41411 posts · Joined 1998. #3 · Sep 18, 2006. All I've ever done is replace the refrigerant oil in the compressor, flush out the system, replace the line to compressor O-rings and add the R-134 access valve adapters and charge it with R-134A. But like Tom said, R-12 works much better.To convert your car’s AC R12 System to R134a, you must first evacuate the R12 refrigerant with a vacuum pump and then use an R134a adapter to inject the new refrigerant. Turn on the air conditioner … Converting your system from R12 to R134a. To the guy