IA_Stingray

I wish to covert my 79 to R134a. I have a new condenser, evaporator, new hoses, and a conversion kit with the new o-rings. I read that I need to replace the orifice tube as well. Should that do it, or do I really need to replace the compressor too?

IA_Stingray

Bump

REELAV8R

The compressor will still have mineral oil left in it from the r-12.
If you use ester oil for the 134A conversion it will be compatible. If you use the Pag oil, I believe it will not be compatible and may form a gel like substance.

http://corvaircenter.com/phorum/read...,515827,515949

IA_Stingray

Okay, that explains why I thought I was reading so much conflicting information. Thank you. However, wouldn't my 1979 have R-4, not R-12?

Easy Mike

It has both. R4 is the type of compressor; radial as compared to the old A6 type. GM changed to the R4s during the 1976 model year run. R-12 is refrigerant.

IA_Stingray

Ah ha! Thanks for your help and patience, gentlemen.

IA_Stingray

If I were to go ahead and upgrade the compressor too, while I'm replacing the rest of the system, what exactly do i look for in a replacement?

'75

Here's what I did, Sanden compressor, parallel flow condenser and Vir eliminator. Yours doesn't have the VIR, so some have claimed the Ford blue orifice tube works better than stock. Also change to the C4 blower motor to improve interior air flow.

REELAV8R

Even if you raplace the compressor there will be some mineral oil residue left in the condensor and the evaporator. So if your thinking replacing the compressor will allow you to use Pag oil, it probably won't. Only way to get it all out is to replace everything. There are flushes available but then the flush is still in the system to contaminate it.
Mine still has the original compressor on a '77 and it works really well.
I agree with the C4 blower fan it's a huge improvement over the C3 fan.

carriljc

Drain as much oil as you can. Remove orifice tube (or control valve- whatever it is that you have). Flush with brakeclean and blow it out with air. Once you it blown out as well as you can you can proceed with reassembly.

Get a new o-ring kit, new orifice tube (or control vlv), a little bottle proper oil to lube your orings, new r-134a fittings, evacuate really well......I used my old compressor in my Nissan pickup. If worse came to worse I would have replaced it....however you can replace it if you know the old one is bad. You can buy pressurized oil cans and R-134a at your local distributor..

Anyway, I converted my Nissan pickup about 10 years ago and it still blows under 40°F. I used to have a saved AC forum link but I've lost it....hmmm....I'll go look but it's been years.

here you go....I read a lot here to do my first conversion:
http://acsource.net/acforum/

20mercury

Some info that might be useful

http://www.corvette-restoration.com/...conversion.htm

http://www.corvetteforum.net/c3/zwed...c/retrofit.htm

http://www.ariazone.com/manuals/Auto...g%20Manual.pdf

agree, this one is very good
here you go....I read a lot here to do my first conversion:
http://acsource.net/acforum/

Lots of different numbers out there on how much oil to put in too. I went with the advice from the last link above. Or basically put in the amount of oil in your original service manual, 11oz for the old A6.

One more if you are an a/c newbie, like me, lol's!
http://www.firstfives.org/faq/AC/ac_charge.html

IA_Stingray

Some great links! Thanks!! Also, just any C4 blower motor/fan will fit??

IA_Stingray

Okay, guys, I really need some help here. First, I attached a couple pics of my old locked up compressor. I ordered a new compressor and it doesn't look the same at all. See the last pic.

Obviously to make that work I'd need completely different brackets. So... Can someone please help me figure out which compressor I need to purchase? I've already got everything else to have the shop convert it to R-134a.

'75

That looks like the pro6ten compressor that is a replacement for the A6, not the R4 like yours.