AC hoses-what to replace with?

914efi · 07-15-2008, 06:05 AM

Do I just buy OEM hoses or is there a newer type better suited for R134?

Thanks

John_AZ · 07-15-2008, 07:02 AM

Art,

I tend to follow a web site www.griffiths.com.

They state:
G) The original rubber a/c hose lines in your car will leak out R12 through the hose's lining. R134a has a smaller molecule than R12 so R134a will leak out sooner than R12. So if you car has a large amount of rubber hose, such as a 40 feet with the 911, then you will be re-charging the system often and that is expensive no matter which refrigerant you use. To prevent refrigerant loss you should consider replacing your old hose lines with "barrier" type hose.

At least change your "O" rings to R134 compliant.

You will read here that many do not change the hoses. R134a is cheap to refill so why go to the bother?

John_AZ
1988 924S R-12
1987 924S R-12
1998 Cherokee R134a and topped up with HarborFreight AC hose + guage=EASY

bud9344 · bud9344's Garage

That statement wasn't made around the time they change over to R134 is it ?
I remember that time when we have to switch to R134 ,they that to convert to R134 from R 12 you do have a lot off thing to do, like completely flush the system and repalce all the O ring and make sure there is no trace off R12 in the system or it my explode.
But now a day nobody does that anymore, Just recover the reminder off the R12, vacuum the system and change all the fitting(R134 fitting). Vacuum it again with R134 machine and recharge.
And you are done.
I remember I have to go to school for that BS when I want to work on the A/C

--------------------------------------------------------------
Bud

87 930 Black R-12
86 951 Black R 134
86 944 N/A Red R 134 (part Car)
87 944 S White R 134
83 944 N/A Black R 134
83 944 N/A White Auto R 134

bud9344 · bud9344's Garage

That statement wasn't made around the time they change over to R134 is it ?
I remember that time when we have to switch to R134 ,they that to convert to R134 from R 12 you do have a lot off thing to do, like completely flush the system and repalce all the O ring and make sure there is no trace off R12 in the system or it my explode.
But now a day nobody does that anymore, Just recover the reminder off the R12, vacuum the system and change all the fitting(R134 fitting). Vacuum it again with R134 machine and recharge.
And you are done.
I remember I have to go to school for that BS when I want to work on the A/C

--------------------------------------------------------------
Bud

87 930 Black R-12
86 951 Black R 134
86 944 N/A Red R 134 (part Car)
87 944 S White R 134
83 944 N/A Black R 134
83 944 N/A White Auto R 134

914efi · 07-15-2008, 09:16 AM

I'm rebuilding the whole system, new compressor retrofit, new condensor and will probably buy bulk hose and rebuild the hoses that way. I had noticed a good deal on one of the oem porsche hoses, so I thought I would check its compatibilty with the new refrigerant. Thanks for the info.

I found that the 924s condenser works with the relocation of one of the mounting brackets. It is cheaper that the somewhat NLA early 944 unit. The connections are in slightly different locations, maybe 1/2" off, but this can be taken up in positioning the hoses I'm pretty sure.

KitCarlsonEMS · 07-15-2008, 10:47 AM

Is the new condenser the parallel flow type? They are better for r134. I was thinking about installing one if my system was weak, however it works very well with the original.

mattdavis11 · 07-15-2008, 12:13 PM

What they told you then, and if anyone is still telling the same story now, is and was completely full of crap. There's no need to even change the o-rings on lines or fittings you don't open, unless they already leak.

It was a huge scam that made a lot of people rich, Dupont was one of them. If you want to replace the hoses, buy a length of generic a/c hose and the fittings you need to splice it in. I'll warn you though, you probably don't have the correct hydraulic presses needed to do this. We build hoses everyday at work, and I can't see anyone having those tools laying around thier garage. It isn't like splicing a coolant hose.

914efi · 07-15-2008, 01:31 PM

924s condenser is the serpentine type, same as 944 early.

So if a good oem hose is available no problem to use? Only a few feet of it in these cars. I can't believe there is 40' in a 15' long 911, that is ~3 times back and forth!

I was thinking of buying a crimp tool or finding a local house to do the work. I also thought good hoseclamps would work just as well, the type that have the band that goes all around. What is the system pressure?

KitCarlsonEMS · 07-15-2008, 02:33 PM

I had a leaky a/c hose in a Volvo and I took it to a belt and hose store in the industrial side of town. The guy had the correct hose and fittings to re-make the hose for cheaper that what I could buy a hose or parts. He used a big Dennison press for the crimps. The result was better than new.

mattdavis11 · 07-15-2008, 03:01 PM

The high side pressures can get to 250-350. It all depends on the ambient temperature and how well your compressor and condensor are functioning. I don't think the type of clamp you have in mind is going to work out very well for you, I'd ditch that idea altogether. We normally charge $20-40 a hose, but they do get more expensive. A long hose can run as much as $125-$150, like the 7 footer that was brought in today. A 911 hose repair would probably be even more expensive, but my compressor to condensor hose only cost $20.

I wouldn't worry too much about what the oem rubber was, any high pressure a/c hose should do. We happen to have goodyear rubber at the moment, but we've had other brands in the past.