R12 replacement gas.

[TJ Hopland]

The first couple years of 134 GM seemed to not change much if anything but then presumably due to customer complaints they appeared to have done a proper re design that seemed to get the performance back.   I'm sure part of the change was sizing of components but they also changed the compressors from the R4 to the H6 which was variable in some way.     Greg or anyone else that knows, do the variable displacement? compressors like the H6 that GM was using in the later 90's vary based on RPM or pressures?    What ever it varies really seems to help the performance at slow speeds and idle which was an area that the early 134's were terrible.

[fishnjim]

R437 is a two component blend containing R134a and R125 and is suitable for use as an R12 replacement.

[Scot Minesinger]

437a is either or close to "Freeze 12", and Freeze 12 is a majority blend of 134 as Greg wrote, and he is right.  You cannot just add in 437 without performing the same cleanout as prescribed for 134.  Hope it all works out.

[cadillac ken]

I have for years been buying R-12 whenever I find it.  I will continue to use it in all my "old" cars that have R-12 systems.  I would join the voices that say if you have an R-12 system, keep it an R-12 system.  Yes it's expensive, but once you have done a vacuum on the system and you are assured there are no leaks, you will probably be able to go for years without a "top off" recharge. I am EPA approved to buy this and to dispense this at my shop.

I say bite the bullet on the price, recharge your system and enjoy your car.  The initial cost will soon be long forgotten and you will not have to worry about any problems wrought with a replacement chemical as the years go by.

To add... remember the 134A needs to run at a higher pressure than R-12, so 134A in an R-12 system will not be as effective in cooling the car (without changing the system components).  That is a big issue here in Florida where air temps are getting ridiculous.  Average heat index here was over 104 degrees these summer months and even this week, in September mind you, temps are still in the 90's. 

[Jeepers Creepers]

1.  Were you able to document the suction and discharge pressures after using the R437 gas>
2.  What oil was used?
3.  Anyone out there using this gas in a 56?
Thanks

Hey Larry, I only remembered to call in today and check on the information you were chasing.

Wayne, my A.C. guy said it was week ago, but is pretty sure it was 25lb suction and 150 - 170lb head pressure. The oil was brand new and I think it was a mineral oil, but don't quote on that bit.

Understand Larry, that is all gobble-de-gook to me, because, as an Air Conditioning guy, I make a great job of lawn mowing, gardening and general yard maintenance. (That's why they call me Art of Grass)

Now, here is a great little story for you, when the system shut down the other day.

I took the Fleetwood out a couple of days ago in about 32 degree heat  (90 for you guys) and the air conditioning was running great...... I did maybe 32 klm (20 miles to you guys) and turned around and headed for home..... About halfway home, the air conditioning became VFO, Very F***ing Ordinary,  to the point, I had to turn it off and drop the window down.

Feeling dejected just doesn't cover it. In desperation, as you do, i turned the air conditioning back on again..... fans running and just a crappy wind coming out of the vents. NOT HAPPY.

I parked the car, went inside and Astrid (wife) said..... How was the Air Cond?....... Fine, I lied...... I didn't feel like even talking about it. Yep, I was sulking.

I was feeling a bit broken and I had this feeling, my car didn't love me anymore..... was the LOVE/LOVE of owning this big ol Fleetwood gone? Had my Fleetwood found someone else to love? I'd rebuilt her engine with hard earned money and lots of love and this is what I get in return.

So, it was about 5:30pm that afternoon in Tin Can Bay, its just going on dusk on a Monday night and Astrid got called in to do a shift at the Marina Bar and Grille....... So now, its just me and the Fleetwood.

So I went out to the garage, started the car up and got a torch to check the receiver dryer, as I was certain, we had a leak and the gas had all but disappeared out of the system. With the engine running sweet, I flicked the air conditioning on to check for bubbles in the dryer.

The fans come on and everything inside the car seems to be working fine.

Oh Christ, now it gets worse, the dryer has no bubbles and looks fine too. Then I cast my eyes over at the compressor, as its next on my list of things that may have crapped themselves. (remember, i'm feeling pretty low about this bloody air conditioning now)

Oh Friggin great, the clutches haven't pulled in and the compressor is just free wheeling. Now i'm thinking the compressor is toasted.

Then, my beady little 57 year old eyes spotted it.... the bloody earth wire was off... Our car has long ago had the fitting changed to single connectors rather than the factory clip.

OH OH OH, quick, turn the engine off. Grab the long nose plyers, give both the earth and power clips a tweak and back on nice and tight.

Start up again, air conditioning on and baby, we have icy cold air again. ...... My car loves me after all and life is grand and best of all, the wife doesn't know and never will.

You have, no idea how relieved I was when that magical Climate Control Air Conditioning began working again....... woo-hoo for my team.

[cadman56]

Fantastic story and ending.