 |
 | Home | Contact Us | FAQ | Search & Site Map | Link to Us |
 | Sign In | Join | Other 45 Sites in Network |
Car Forum / Mazda / Mazda Miata / June 2007R12 to R134a conversion in MX5 Miata
Anyone have a 'handle' on converting the AC compressor oil in a 90 Miata from R12 compatible to R134a, etc. Any hidden items/issues I should be aware of, etc. Whats been your experience in AC efficiency after conversion to R134a, etc.? Thanx > Anyone have a 'handle' on converting the AC compressor oil in a 90 > Miata from R12 compatible to R134a, etc. What ever you do, do it RIGHT! That means evacuating the system, removing the compressor, draining all the oil and replacing it with oil made for R134a (the remove the compressor step is usually skipped, it shouldn't be.) Replace the accumulator or receiver/drier (whichever the Miata uses) and then evacuate the system for a loooooooog time to be sure you've removed as much of the old Freon, oil and water as possible, then recharge with R134a. > Any hidden items/issues I should be aware of, etc. Probably but I don't know of any? As always, check Miata.net http://www.miata.net/garage/r134.html > Whats been your experience in AC efficiency after conversion to > R134a, etc.? Did it in a Jeep Cherokee, I really didn't notice any decrease in cooling.  SignatureXS11E, Killing all posts from Google Groups The Usenet Improvement Project: http://blinkynet.net/comp/uip5.html If I were going to keep the 90, I'd replace the compressor with a new one already setup for 134a. (Ten years of wear and all that.) If the A/C is currently working ok with R12, I'd leave well enough alone. > > Anyone have a 'handle' on converting the AC compressor oil in a 90 > > Miata from R12 compatible to R134a, etc. [quoted text clipped - 18 lines] > Did it in a Jeep Cherokee, I really didn't notice any decrease in > cooling. > If I were going to keep the 90, I'd replace the compressor with a > new one already setup for 134a. There's no such thing, to set up a compressor for 134a you drain out all the oil and replace it with oil made for 134a. Since the compressor is/was made/rebuilt for a car using R12 it will almost certainly have R12 oil in it. > (Ten years of wear and all that.) Agreed. That what I did when I converted my Jeep Cherokee. I figured if I had to remove the compressor I wasn't going to put the old one back on when I could get a rebuilt for a reasonable price that included a warranty. > If the A/C is currently working ok with R12, I'd leave well enough > alone. It's getting very hard to find R12 around here and those who have it are VERY proud of it. If there's anything wrong with the system that requires more than 1 pound of R12, I'd probably do the conversion or at least think about it.... SignatureXS11E, Killing all posts from Google Groups The Usenet Improvement Project: http://blinkynet.net/comp/uip5.html The compressors come preloaded with either 134a & oil or R12& oil. At least at our local parts stores. Most of the non special order compressors in stock are setup for 134a. > > If I were going to keep the 90, I'd replace the compressor with a > > new one already setup for 134a. [quoted text clipped - 18 lines] > requires more than 1 pound of R12, I'd probably do the conversion or at > least think about it.... > The compressors come preloaded with either 134a & oil or R12& oil. Correct, and a compressor for a NA Miata will come with R12 oil since that's what the vehicle used originally. SignatureXS11E, Killing all posts from Google Groups The Usenet Improvement Project: http://blinkynet.net/comp/uip5.html No compressor I ever bought had oil in it. The oil absorbs moisture. The proper oil is supplied seperately. >> The compressors come preloaded with either 134a & oil or R12& oil. > > Correct, and a compressor for a NA Miata will come with R12 oil since > that's what the vehicle used originally. The last compressor I bought came with both an oil and 134a refrigerant load. The previous one for an 89 MPV (orig was R12) was a replacement setup for 134a. All I'm saying is that as the R12 becomes more expensive and harder to get, the replacment market is making available replacments intended for 134a. Seems that shipping with a refrigerant and at least partial oil load helps the reliability of the replacement. > No compressor I ever bought had oil in it. The oil absorbs moisture. The > proper oil is supplied seperately. [quoted text clipped - 3 lines] > > Correct, and a compressor for a NA Miata will come with R12 oil since > > that's what the vehicle used originally. The oil in a new compressor is assembly oil. I very much doubt that refigerant was loaded into the compressor since it would escape during fitting. The EPA would be unhappy. More likely it was nitrogen to purge any air out of the compressor after assembly. > The last compressor I bought came with both an oil and 134a refrigerant > load. The previous one for an 89 MPV (orig was R12) was a replacement [quoted text clipped - 13 lines] >> > Correct, and a compressor for a NA Miata will come with R12 oil since >> > that's what the vehicle used originally. > The oil in a new compressor is assembly oil. Wrong. It's the proper oil for the vehicle. > I very much doubt that refigerant was loaded into the compressor > since it would escape during fitting. The EPA would be unhappy. > More likely it was nitrogen to purge any air out of the compressor > after assembly. None of the above, all the compressors I've seen, and that's a whole bunch of 'em, new and rebuilt come with nothing but the oil and caps over the fittings to keep the oil in. SignatureXS11E, Killing all posts from Google Groups The Usenet Improvement Project: http://blinkynet.net/comp/uip5.html > No compressor I ever bought had oil in it. The oil absorbs > moisture. The proper oil is supplied seperately. Every one we ever bought, and we used to replace a dozen or more annually, had oil in it. SignatureXS11E, Killing all posts from Google Groups The Usenet Improvement Project: http://blinkynet.net/comp/uip5.html >> No compressor I ever bought had oil in it. The oil absorbs >> moisture. The proper oil is supplied seperately. > > Every one we ever bought, and we used to replace a dozen or more > annually, had oil in it. Yep, they have assembly oil. >>> No compressor I ever bought had oil in it. The oil absorbs >>> moisture. The proper oil is supplied seperately. [quoted text clipped - 3 lines] >> > Yep, they have assembly oil. Wrong, they have the correct refrigerant oil, NOT assembly oil. SignatureXS11E, Killing all posts from Google Groups The Usenet Improvement Project: http://blinkynet.net/comp/uip5.html The last replacement compressor I bought for personal use was for a 98 Chev Cavalier earlier this year. The label specified the amount and type of oil and refrigerant preloaded into the compressor. > >>> No compressor I ever bought had oil in it. The oil absorbs > >>> moisture. The proper oil is supplied seperately. [quoted text clipped - 5 lines] > > Wrong, they have the correct refrigerant oil, NOT assembly oil. > The last replacement compressor I bought for personal use was for > a 98 Chev Cavalier earlier this year. > The label specified the amount and type of oil and refrigerant > preloaded into the compressor. They can't preload refrigerant into the compressor, it's opened during installation, how would they prevent the refrigerant from escaping? The label merely says what type of oil is in the compressor, R12 or 134a. Compressors are oil filled and the extra has to be removed. You drain the old compressor into a measuring cup, drain the new compressor and put back the same amount of oil that was in the old one. Look in your shop manual or Google it up. SignatureXS11E, Killing all posts from Google Groups The Usenet Improvement Project: http://blinkynet.net/comp/uip5.html > Compressors are oil filled and the extra has to be removed. You drain > the old compressor into a measuring cup, drain the new compressor and > put back the same amount of oil that was in the old one. > > Look in your shop manual or Google it up. This link shows a cutaway of a rebuilt Denso A/C compressor and it is listed as "100% replaced with OE-Specified oil. OE-specified oil does not sound like assembly oil to me. http://www.densoproducts.com/product.asp?productCategoryID=5 Damn, agreeing with Leon and XS11E, what's going on here? Pat > Damn, agreeing with Leon and XS11E, what's going on here? We'll allow you to exhibit some *small* doubts as to the validity of the photon drag theory of white paint. However, allow me to present for consideration this one indisuptable fact: My Miata is white and it goes as fast as I want. SO THERE! SignatureXS11E, Killing all posts from Google Groups The Usenet Improvement Project: http://blinkynet.net/comp/uip5.html The label was on a tag wired to the compressor, not on the compressor. While you are supposed to minimize loss of refrigerant, 134a is not nearly as bad as R12, etc, and can be bought over the counter by anybody. (at least in my area) The oil preload is the oil for normal use. The compressor I mentioned has more than one OEM application. It was stocked with "GM" oil, and instructions came with it on how to change to other OEM oil viscosities. They went something like this-- Amount of oil in compressor was listed on tag. Drain and measure amount drained. Subtract remainder from dry system requirement. Add appropriate amount to closed system under vacuum if applicator available. If not pull vacuum after or during adding oil. Add measured amount of refrigerant. Turn compressor by hand to allow oil to distribute and make sure compressor is not oil locked. I just added about 1/2 the required oil at a midpoint coupling in the system, and the rest split between the compressor inlet and outlet hoses. Then closed and pumped down the system before adding 134a. The original compressor failed and dumped metal into the system. The coils and hoses had to be flushed, and the receiver dryer replaced. > > The last replacement compressor I bought for personal use was for > > a 98 Chev Cavalier earlier this year. [quoted text clipped - 11 lines] > > Look in your shop manual or Google it up. You could try to get hold on a distributor of R413A. This is good replacement-fluid for R12 without exchanging other hardware. Works great in my 91 for 2 years now... Jeroen -- The Silver Striped 91B Crystal White Miata - http://miata.feelders.com Mazda MX-5 Club of the Netherlands Technical and Websitecommission Member - Meguiar's Clinics -- | Anyone have a 'handle' on converting the AC compressor oil in a 90 | Miata from R12 compatible to R134a, etc. Any hidden items/issues I | should be aware of, etc. | Whats been your experience in AC efficiency after conversion to R134a, | etc.? | Thanx |
Reply to this Message |
 Sign In
 Join
 My Latest Posts My Monitored Threads My Blog My Photo Gallery My Profile My Homepage Start New Thread Enable EMail Alerts Rate this Thread
|
©2008 Advenet LLC Privacy Policy - Terms of Use
This website includes both content owned or controlled by Advenet as well as content owned or controlled by third parties.