1970 Chevelle A/C - GM Forum - Buick, Cadillac, Chev, Olds, GMC & Pontiac chat


Chevrolet When starting new posts, please specify YEAR, MAKE, MODEL, ENGINE type, and whatever modifications you have made.

Reply
 
 
 
Thread Tools Search this Thread
Old 06-02-2016, 08:56 AM   #1
Senior Member
Posts like a Turbo
Thread Starter
 
vendo's Avatar
 
Join Date: Sep 2010
Location: MASS
Posts: 480
Thanks: 0
Thanked 1 Time in 1 Post
vendo is on a distinguished road
Default 1970 Chevelle A/C

I am putting in a new compressor and dryer,i had 134 in,i am going to switch back to R12 I know I need to use mineral oil..is there anything else I need to do?
vendo is offline   Reply With Quote
Old 06-02-2016, 10:23 AM   #2
Senior Member

Certified GM nut
 
Tech II's Avatar
 
Join Date: Feb 2014
Location: Worcester, Ma.
Posts: 2,150
Thanked 785 Times in 614 Posts
Tech II has a reputation beyond reputeTech II has a reputation beyond reputeTech II has a reputation beyond reputeTech II has a reputation beyond reputeTech II has a reputation beyond reputeTech II has a reputation beyond reputeTech II has a reputation beyond reputeTech II has a reputation beyond reputeTech II has a reputation beyond reputeTech II has a reputation beyond reputeTech II has a reputation beyond repute
Default

Why are you switching back?

You are going to run into a serious problem if you do.....you are never going to get rid of all that pag oil in the system....it will be trapped in the evaporator and condenser, lines , etc.....

On conversions, you can mix a little mineral oil with pag, but the opposite is not true.....

If your heart is set on R12, and you have access to it, make sure you get an R12 compressor,and you must do a complete "flush" of the system, to get rid of the pag oil....
Tech II is offline   Reply With Quote
Old 06-02-2016, 10:27 AM   #3
Senior Member
Posts like a Turbo
Thread Starter
 
vendo's Avatar
 
Join Date: Sep 2010
Location: MASS
Posts: 480
Thanks: 0
Thanked 1 Time in 1 Post
vendo is on a distinguished road
Default

Quote:
Originally Posted by Tech II View Post
Why are you switching back?

You are going to run into a serious problem if you do.....you are never going to get rid of all that pag oil in the system....it will be trapped in the evaporator and condenser, lines , etc.....

On conversions, you can mix a little mineral oil with pag, but the opposite is not true.....

If your heart is set on R12, and you have access to it, make sure you get an R12 compressor,and you must do a complete "flush" of the system, to get rid of the pag oil....
How do I get it out of there I have a 30 pound can of 12, pulling vacuum won't get rid of all that oil ?
vendo is offline   Reply With Quote
Old 06-02-2016, 10:34 AM   #4
Senior Member
Posts like a Turbo
Thread Starter
 
vendo's Avatar
 
Join Date: Sep 2010
Location: MASS
Posts: 480
Thanks: 0
Thanked 1 Time in 1 Post
vendo is on a distinguished road
Default

I used ester oil when I had the R12 and I just used fittings to put the 134 in..I did not use any pag oil...unless its in the R134 cans..I was told that you have to reset the POA valve for 134 also..
vendo is offline   Reply With Quote
Old 06-02-2016, 07:50 PM   #5
Senior Member
Posts like a Turbo
 
Join Date: Oct 2011
Location: SC
Posts: 247
Thanked 50 Times in 43 Posts
garagerog is a jewel in the roughgaragerog is a jewel in the roughgaragerog is a jewel in the rough
Default

Congrats on that 70 Chevelle classic, from an owner of a 71 Chevelle SS. I assume you're wanting to return to the R-12 system to make your car as original as possible and my hats off to you for that. On my part my Chevelle did not come with factory a/c and to be able to drive it year around after moving from the NW to SC I installed a Classic Industries aftermarket a/c system, my Chevelle original? no, but I can drive it when I want and that'* what is important to this original owner old man. Sorry I can't give you any advice on a R-12 system, just wanted to share my story with you. Good Luck.
garagerog is offline   Reply With Quote
Old 06-02-2016, 07:59 PM   #6
Senior Member
Posts like a Turbo
Thread Starter
 
vendo's Avatar
 
Join Date: Sep 2010
Location: MASS
Posts: 480
Thanks: 0
Thanked 1 Time in 1 Post
vendo is on a distinguished road
Default

I have it going with R134,4 cans I put in of the 12 oz,still got bubbles in site glass..i will drive it a little and see what happens,it goes to 60 and little lower on vent temp guage..I was told you cant go back to R12 after 134 unless you replace everything..oh well.
vendo is offline   Reply With Quote
Old 06-09-2016, 02:59 AM   #7
Junior Member
 
Xerxes's Avatar
 
Join Date: Mar 2014
Posts: 5
Thanks: 0
Thanked 0 Times in 0 Posts
Xerxes is on a distinguished road
Default

The sight glass isn't an effective indicator with 134a, only works with R-12.
Yes, I think you should use R-12, the system was designed for it and it is more
effecient than 134a. To go back to R-12, you have to flush everything but the
compressor, replace the accumulator,run mineral oil thru the compressor to
flush the other oil and recharge to spec with R-12 and proper amt. mineral oil.
You can get advice on anything related to this on AirCondition.com
Xerxes is offline   Reply With Quote
Old 06-09-2016, 03:01 AM   #8
Junior Member
 
Xerxes's Avatar
 
Join Date: Mar 2014
Posts: 5
Thanks: 0
Thanked 0 Times in 0 Posts
Xerxes is on a distinguished road
Smile 70 Chevelle AC

The sight glass isn't an effective indicator with 134a, only works with R-12.
Yes, I think you should use R-12, the system was designed for it and it is more
effecient than 134a. To go back to R-12, you have to flush everything but the
compressor, replace the accumulator,run mineral oil thru the compressor to
flush the other oil and recharge to spec with R-12 and proper amt. mineral oil.
You can get advice on anything related to this on AirCondition.com
Xerxes is offline   Reply With Quote
 
 
Reply

Related Topics
Thread Thread Starter Forum Replies Last Post
Pic of my 68 Chevelle bowtiebob Your Ride: GM Pictures & Videos 9 03-15-2012 02:47 AM
chevelle with bonneville interior PICS billythekid General GM Chat 14 10-07-2010 02:56 AM
I like the Chevelle better! Krazy Kyle Lounge 5 08-20-2004 04:03 AM
1970 LS6 454 Chevelle Auctions...... givemebreak Lounge 7 04-18-2004 12:41 PM
05 chevelle?? GAMEOVER Lounge 17 02-23-2004 12:18 PM


Tags
air conditioning, chevelle 1970

Thread Tools Search this Thread
Search this Thread:

Advanced Search

Posting Rules
You may not post new threads
You may not post replies
You may not post attachments
You may not edit your posts

BB code is On
Smilies are On
[IMG] code is On
HTML code is Off
Trackbacks are Off
Pingbacks are Off
Refbacks are Off



All times are GMT -4. The time now is 04:41 AM.


We are a participant in the Amazon Services LLC Associates Program, an affiliate advertising program designed to provide a means for us to earn fees by linking to Amazon.com and affiliated sites.