Switch back A/C from R134a to R14?

[jsimpson]

Any newstand that carries car books.
or
Prestige Publishing
PO Boix 2786
Grapevine, TX 76099

 

[Bob Chadwick]

Found it on the web at www.motolit.com.

Thanks for the help.

By the way, the specialty air conditioning shops that I am talking to are recommending changing the compressor as well when you make the conversion claiming that it will fail after several months of use. Your post, and several others, don't jive with this. Everyone has an opinion and I guess that the old saying comparing opinions to the human posterior is true.

Bob

 

[69MyWay]

Bob,

I have not had one fail, and one over a dozen conversion using the old R12 compressor.

 

[Bob Chadwick]

Thanks Chris.

Ithink I have finally figure out what I'm going to do. There is a professional shop here that for $50 will go over the system and tell me what the problems are. If it doesn't involve conversion, I think I will let them do the repairs, which they will give me a $50 credit for. If it needs to be converted, I will look elsewhere as they will want to change the compressor as well.

First I have to get the car back. Took it to the shop for a new carb and a tuneup. Also to put the 3 screws back in on the lower left hand dashpad. I talked to him yesterday. He quoted me half and hour and ended up putting 3 hours just into those screws. With the new dashpad and lower panel they just did not want to line up. He's going to stick to his original estimate and so I'm happy amd he's not.

Bob

 

[69MyWay]

My new passenger side dash panels and upper fit like poop. I am still trying to align them to look better. I have way more than three hours, and counting. I think you got a real bargain there.

 

[Bob Chadwick]

Chris,

Keep at it. They will look great when you get them in. I am very happy with the way they turned out. I actullay dyed the passenger side panel and the windshield trim and they came out looking really good.

As to the a/c, its official. A leaking compressor and an $1,100 switch over to R134. I had two estimates for about the same amount and went with the shop that solely does a/c work. Maybe today, but more likely I'll have it tomorrow.

Bob

 

[Bob Chadwick]

Got it back last night. Drove about two miles and it started to smoke and lost all cold air. Took it back this morning and found out that the condensor leaks and that all of the R134 blew out with the oil smoking as it hit the manifold.

The whole system has now been replaced with the exception of the evaporator (I think that's what the part in the passenger compartment is called) and if that fails I'm not going to be a happy camper.

Bob

 

[jsimpson]

Well I hate to tell you, but I had to replace the evaporator on my 94 Dodge RAM and on my 78 Vette. When I install air in my 70 Vette, it will have a new evaporator ($171.00 at Discount Auto Parts).

 

[Bob Chadwick]

John,

Its not the cost of the evaporator that bothers me. I understand that the whole dash has to come out to replace it and I just got the darned thing back together completely for the first time in 6 months last night.

Bob

 

[joevette57]

John,
If you're going through go the expense and painstaking labor to replace the evaporator, I BEG YOU.... PLEASE PLEASE PLEASE... go buy a QUALITY part from a reputable supplier.
Over the years I have heard and seen so many nightmares from fellow Vette (and other cars as well) that have had to redo repairs because of Discounts lousy quality auto parts.
I believe evaporators are still available from GM. If not use a Quality Vette supplier such as Last Detail or Rik's Corvettes.
The few extra dollars you might have to spend will be well worth the knowledge that you're not going to have to repeat the task a few month's later.
Sure Disount will warrantee the part..... But you're going to eat the labor.

Regards.
Joevette57

 

[jsimpson]

Thanks for the warning, but actually, I'm using the evaporator from Discount in my Dodge RAM because MOPAR evaporators are so lousy that they're usually good for only about 2-3 years down here. I have a Vette evaporator from my 78 that I accidentally poked a hole in. I heliarced it and will use it in my 70.
I figure whatever aftermarket evaporator that Discount sells has GOT to be better then the MOPAR evaporator!

 

[kbrews]

R12 vs R134a temperature?

Good thread. I am a new vette owner, and have a few questions. But first, here is the scenario..... I have a 1981 with apparently the original R12 system. It shoots no cold air. Also, the fan seems to be really week no matter on air, vent, or heat. So here are my questions:
1. Does R134a cool as good as R12?
2. Do the newer compressors work better (ie R134a), making the inferior R134a freon work just as good or better anyway? So not really a factor?
3. Is there a beefier fan and air handler that I should install? Get it where?
4. Do I understand from all the comments in this thread that best case I can convert to R135a, not change the pump, or the condenser... just coolant, the compressor oil, and some O rings? And "worser" case, also change the compressor, but only if it is bad?
Thanks for any help. Keith

 

[kjfassoc]

I have changed many ac systems over to 134, all I have ever had to do is evacuate the old freon with it came most of the old oil, put the new oil for 134, in add the gas. It has been my experience that most ac systems will leak. I expect to add a can every now and then. your not talking that much money and it cools just as well.

 

[kjfassoc]

Sorry I did not mention adding new fittings, they are a different size for 134

 

[john1977]

I switched to 134 going on 4 years ago and stayed with my old compresor and have had no problems.Only other thing replaced were the o-rings.Radiator shops make big money telling you all the things you need to change.

 

[Koop]

I switched to R134a a few years back, knowing what I know now I would not do that again. The car will remain R134a until I need to completely overhaul the system again at that time it may go back to R12.

I did have to put a very, very large electric pusher fan on the condenser to keep the head pressure down so now my hood does not open quite all of the way and the fan is pretty loud, I don't like it.

I think the R12 was colder, but I have nothing to back that statement up.

 

[john1977]

I switched to R134a a few years back, knowing what I know now I would not do that again. The car will remain R134a until I need to completely overhaul the system again at that time it may go back to R12.

I did have to put a very, very large electric pusher fan on the condenser to keep the head pressure down so now my hood does not open quite all of the way and the fan is pretty loud, I don't like it.

I think the R12 was colder, but I have nothing to back that statement up.

Dont know why you would need a pusher fan unless you have a cooling problem, i have nothing more than my 18" flex fan and can idle all day and never go over 200 degrees with air on.

 

[Koop]

Dont know why you would need a pusher fan unless you have a cooling problem, i have nothing more than my 18" flex fan and can idle all day and never go over 200 degrees with air on.

It was a head pressure issue in the AC, not the cooling system, the AC system was making to much head pressure. I believe the other alternative might've been to replace the condenser with a model with more cooling capability but I don't think there was one available at that time so the pusher fan was the answer.