Expansion valve
Thread Starter
Melting Slicks
Joined: Sep 2006
Posts: 2,811
Likes: 469
From: Wichita Kansas
Expansion valve
Is it necessary to change both the expansion valve and the POA on the stock system of a '72 if you are converting to 134A? Thanks
NEVER MIND, I WILL REPLACE IT ANYWAY
NEVER MIND, I WILL REPLACE IT ANYWAY
Last edited by kansas123; Sep 4, 2021 at 02:06 PM.
Race Director
Joined: Jul 2015
Posts: 13,082
Likes: 3,399
From: SW Florida.
I think the 72 expansion valve is acceptable. It is the 73-77 VIR that is the real pain in the tail. Are you talking replacing them with new ones that are in better condition? Or are you talking replacing the style of air conditioning? Because if you’re going to change it out, do you want to go with the 78 and newer orifice tape. But then you have to change your liquid line because the fitting on the end is different. And you have to change the two big rubber hoses because the fitting on the end of the one from the firewall back to the compressor is also different. Long as you’re in a deep you might as well take that a six and throw it in the river and get a sanden in there. That a6 compressor is actually a very powerful unit. Good enough for a 2 ton whole house air conditioning set up. But it doesn’t like to cycle. It wants to run all the time or be off all the time.
Last edited by derekderek; Sep 4, 2021 at 04:37 PM.
Thread Starter
Melting Slicks
Joined: Sep 2006
Posts: 2,811
Likes: 469
From: Wichita Kansas
Many things to think about. Since I had to replace the main a/c hose/muffler piece, I thought I would replace the POA with one for 134A ad then wondered if the expansion valve should also go. Having much trouble with those connections as they are 50 yrs old. Using PB on them presently, will try again today. Would rather not replace those if I don't need to (for 134A), libel to break something. If it all came apart easy/easier, I would continue with it, but am hedging toward just replacing the hose, draining the compressor and moving on with the very basic conversion and hoping for the best. If it doesn't work oh well. Thanks Derek
Race Director
Joined: Jul 2015
Posts: 13,082
Likes: 3,399
From: SW Florida.
ave you replaced the main hose yet? if not, hold off until you see whether or not you need to replace enough that a 78-up style is doable. hate to pay 60 to 100 for a 72 piece then find out you need the later version after all and the guy don't wanna take it back... wichita KS. AC season almost over anyway. i am moving to s florida. AC season is feb to december...
Pro
Joined: Nov 2019
Posts: 648
Likes: 353
From: Portland, Oregon
Basic r134 conversion is flushing the entire system and replacing every seal. R134 is already banned from use in new cars as it is also a greenhouse gas and shouldn’t be vented to atmosphere. Sanden compressor and orifice tube system are good upgrades. I like r12 as it is what this car’s ac was designed for, readily available and facilities exist to evacuate old refrigerants environmentally. Pressure test before evacuating and it will stay sealed for decades.
Thread Starter
Melting Slicks
Joined: Sep 2006
Posts: 2,811
Likes: 469
From: Wichita Kansas
ave you replaced the main hose yet? if not, hold off until you see whether or not you need to replace enough that a 78-up style is doable. hate to pay 60 to 100 for a 72 piece then find out you need the later version after all and the guy don't wanna take it back... wichita KS. AC season almost over anyway. i am moving to s florida. AC season is feb to december...
