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I need to change my system from r12 to r134a freon. How do I drain the old compressor oil and how do I know how much of the new oil would need to put be in? Would I need to change any hoses and/or o-rings even if it is not leaking?

Also, I read that the original compressor may not be compatible with the new r134a freon. Is this true?

Thanks.
 

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heres list that u will want to consider replacing,
compressor (make sure it is r134 compatable, if you can clean out the o.e compressor well enough i dont see any harm in using the o.e compressor)
all new lines
new evap canister
and one more thing i cant remember.

i work at a shop that does all sorts of ac and if u just use all the o.e stuff that had r12 in it u will contaminate the r134 and if u do end up taking it to a shop they will charge extra to evap the contaminated stuff.

as far as how much r134a it will be the same as the r12. no more than 2 lbs tho
 

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First off there is a lot of wrong info here. The old compressor is fine. You don't need new lines. "new evap canister" never heard of one. They don't exist. If you meant the reciever / drier then yes. You need one with a high enough number dessicant level for the r134a compatible. My suggestion is to buy it from http://hondapartsnow.com or your local honda dealer. Online will be cheaper. Yes you should replace all the o-rings. They should be green in color and r-134a compliant. Yes you should drain the compressor oil, Your going to have to take it out unless you can get it out with the hoses off and compressed air. If you take the compressor out you can also take off its rear sheet metal sheild and remove its high pressure release valve to get more oil out if needed. You can also shoot compressed air through the hoses to try to get stuff out. If you cover the other end with a white paper towel or rag you should be able to tell if you get anything out. You should put a certain amount of oil back in the compressor that is r134a compliant. You should also put small amount in the new reciever / drier too. The reciever / drier install should be the last thing you do. You should keep the reciever drier capped up until ready to install. Once you add the oil to it you should install it imediatley. You should reinstall any hoses or whatever you take off the compressor imeadiatley after adding fresh r134a compliant oil. Lastly you should always vacuum your system for 30 minutes prior to charge. This gets rid of moisture, water, water vapor that is bad for the refrigerent and the system. It also lets you know if you have a leak if it can't hold a vacuum for 30 minutes or longer.

The r134a compliant orings you might be able to buy a kit that has only them at the parts store for the lude. You have to ask the parts counter guy that knows his shit and cares. Otherwise just do a google product search which is different then just an average google search. State your year lude 19xx and the words prelude a/c orings should work. If you need help let me know. I might just add a link here once I get done. Next the r134a compliant oil bottle should remain capped when not pouring it out. It is very hydroscopic. That means it attracts moisture, water, and water vapor very rapidly and asorbs it which is the way it was designed for your a/c system. The same reason for capping the compressor and receiver / drier like I said above.

Also I have not found one singal reciever / drier aftermarket that had the proper binary switch port on them. I ordered 3 different ones and returned them all. Looked online aswell. The binary switch is there to shut off the compressor if the pressure coming from it gets too high or too low. Binary meaning dual purpose or two like bicycle. The one from honda or online honda dealer has the port and a new switch. You can't order it without the switch. Basicaly the extra cost is the switch. Look at the cost of the switch by itself on their catalog. I haven't seen any reciever / drier including the honda new ones that have the glass sight glass. If you want more info do an advanced search with my user id.

Edit Links:

http://www.partsgeek.com/gbproducts/WC/6051-01013466.html?utm_source=google&utm_medium=ff&utm_content=YN&utm_campaign=PartsGeek+Google+Base&utm_term=1979-1996+Honda+Prelude+A%2FC+O-Ring+Kit+Santech+W0133-1830266+79-96+Honda+A%2FC+O-Ring+Kit+1987+1995&fp=pp&gbm=a

http://www.google.com/search?q=5240...gc.r_pw.&fp=aebdb1407c6fdbf1&biw=1280&bih=539



heres list that u will want to consider replacing,
compressor (make sure it is r134 compatable, if you can clean out the o.e compressor well enough i dont see any harm in using the o.e compressor)
all new lines
new evap canister
and one more thing i cant remember.

i work at a shop that does all sorts of ac and if u just use all the o.e stuff that had r12 in it u will contaminate the r134 and if u do end up taking it to a shop they will charge extra to evap the contaminated stuff.

as far as how much r134a it will be the same as the r12. no more than 2 lbs tho
 

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i figured the op was atleast gunna look at the stickies on this. thank you for clarifying what i couldnt. i did have the drier and the "evap canister" mixed up. at my shop that term gets used often. the reason i said new lines was because usually its to much of a pain in the ass to sit there and use compressed air and wait for all the old stuff to come out. the new lines usually come with new o-rings and in general better shape. it might be better for the op to get everything cleaned out and then have a shop charge it. i think it would be rather difficult to vacuum the lines and drier and all that fun stuff at home. when shops do it they have the machine that has all the gauges for the high and low side and how much oil to add while putting in the r134a, i cant say if heard of someone adding pag oil manually into the lines. but to each their own.
 

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[ame]http://www.amazon.com/Four-Seasons-26777-Conditioning-System/dp/B0023TOKWU/ref=sr_1_90?s=automotive&ie=UTF8&qid=1343538957&sr=1-90&keywords=honda+prelude+a+c+kit[/ame]
 

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Wow let me get this straight. You would rather charge your customer $385 dollars for new hoses because your mechanic is too lazy to clean the old ones. Thats what it would cost me for honda oem replacement hoses at my dealership. Or lets say this guy bought them online to save money at http://hondapartsnow.com, $280 plus about $15 shipping?? Lets say he wanted to replace his lines with aftermarket lines that would be the cheapest at http://rockauto.com that might and probably isn't the same nor the same qaulity as his originals he would still be paying $132. By the way one the hoses is unavailable at rockauto.com and you can sure bet you would be looking at $160 -$200 that the local autoparts store will charge him or your shop if your a private shop. Or should say that is what he will be billed for.

Not saying that it would be a bad idea to replace 20 year old hoses but the hoses he has might be just fine and thats just a fucking rip-off.

EDIT: The mechanic is already going to have both ends of the hose off to replace the orings. Also you always add some oil to the compressor especialy if it is a new one but even if it isn't if you are truly sucessful at removing almost all the old oil the minute that you turn on the system to charge it and add oil with the charge your fucking up the metal on metal of the veins to housing of the compressor. You wouldn't start a rebuilt engine without greasing the bearings and priming the oil pump would you?? Same logic. Its not hard to vacuum out your system at home. You just need a vacuum pump. You can get them for a $100-$120 that work great then you can do everything yourself. Which I prefer. Or if you have an air compressor you can buy a vacuum valve box for under $20-$30. The good thing is you can use them over and over again. If your not comfortable vacuuming and charging the a/c then by all means leave it up to an expert. You need to know your facts better before giving advice. I have charged many a/c systems myself over 24 years myself. Not shop talk from coworkers. Next you were unfamiliar with the do it your self options and less face it with our cars not beeing worth much most of the people onhere are looking for diy advice like the op.

I have also read many textsbooks required for a/c certification. Worked in an autoparts store for first job. Look at auto parts catalogs daily online. Best friend works as a parts manager for a dealership. We talk about his job plenty. Lastly our mutual friend is the dealership shop forman and has worked there for 20 years so I keep in touch with both sides of the industry.
 

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lol what im saying is that yes my salesman tells us to have the customer buy new lines and compressor and drier. for 2 reasons.
1. more money
2. the fact that most a/c companies will not offer a warranty unless all the a/c has been replaced with brand new.

i am one of the mechanics that does the basic work. i asked my ase certed guy why we dont just blow them out and he said that the company we buy our a/c stuff through wont give warranty unless we replace it all. needless to say we dont see many conversions at my work
 

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I need to change my system from r12 to r134a freon. How do I drain the old compressor oil and how do I know how much of the new oil would need to put be in? Would I need to change any hoses and/or o-rings even if it is not leaking?

Also, I read that the original compressor may not be compatible with the new r134a freon. Is this true?

Thanks.
Why do you need to change to r134a?
 

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Please read through the entire AC thread "Freeze 12 or R-134a". Or click the link in my sig "A/C Rebuild (R-134a)":
http://www.preludepower.com/forums/showthread.php?t=333672

*edit*
And yes, the R-134a parts are actually a little different than the R-12 parts. The replacement lines have a larger ID and OD, the evaporator has a larger fin area, the expansion valve is optimized for R-134a, the drier is for R-134a, the PAG oil is for R-134a, and the o-rings are better for temperature changes Delta(T).

The parts which remain unchanged: compressor, condenser, brass line, electrical relays.

If you use a new drier that doesn't support the binary switch, there is a way to make it work without the binary switch. Complete the binary circuit with a short bit of wire.
 

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The r134a compliant orings are also made to hold in the smaller molecular r134a. I also replaced my expansion valve.
 

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Triple if you can show me hoses or an evaporator core like you said that fits our car I am all ears. I have not seen such. After all we are talking about our car. As far as the hoses you mention I don't see how it would make much difference. They are still going to have the same restrictions at either end to bolt up to the compressor and stock size evaporator core.
 

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For the new R-134a compliant evap, I had to remove the styrofoam/insulator inside the box. Once that insulation was removed, the evap fits in like a glove. You might be able to have perspective of it's size by comparing it to the condenser pictured above.
 

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Thats a good pic man. What brands did you go with? I will use that pic to look at my condensor. Its suppose to be right but never checked it. Still in the box from when I bought it back in say '04 from ebay for $35.
 

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$35 new? Thats a really good deal. A some of the brands I think were Four Seasons, Spectra, AC Delco. The AC Delco lines are really good quality. I replaced everything but the lines that are all-metal.
 

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yeah it was new and a realy good deal thats why I went ahead and bought not knowing if I needed it.
 

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yeah my condensor looks just like that. I was a little worried because of the cost. Mine use to be barried. I just went out and looked at it. The brand is TYC. Your silver pipe is painted black like the rest of it.

What brand is your evaporator core? Its been awhile since I looked at mine but didn't remember that angled pipe. Mine both come straight out parallel to the ground.
 
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