Skidog214

I recently purchased a 1985 911. The records which accompanied the car state that the AC was converted to R134 many years ago. The air was not blowing cold, so I went to have it checked. The technician told me the fittings were changed but that the hoses are not barrier hoses. How can one tell if the hoses are, in fact, barrier hoses?

Thankjs

Vane

The refrigerant hoses are not your basic garden hose, so there most likely is some
script on the hoses. With this you hopefully can figure out if they are barrier hoses.
You have a reason to doubt your technician?
I have also a ´85 911 and have the original hoses as the barrier hoses was quite
expensive. I still have R12 in my system.

Skidog214

No reason to doubt the technician; it is a new relationship,, but he is with a reputable shop.
Records from about 10 years ago show the AC being converted to R134. I just thought it was odd that the system would be converted to R134 without also changing the hoses.

Is/was it a common practice?

76FJ55

Yes, I think it is relatively common to convert to R134a without replacing the hoses. It is not ideal, but for cost and convenience I think a lot were done that way.

oldskewel

I have an '85 cabriolet, and due to where I live and the fact that the top is always down anyway, I fully removed the AC a few years ago.

Removing and replacing all the hoses would be a pretty major job. You can see the ones in the engine bay of course, but they run up to the front condenser (at the front of the trunk) and evaporator (at the back of the trunk). LOTS of hose, and significant weight savings and accessibility improvement by removing it all.

So I can completely understand why someone would not replace all the hoses when switching to R-134a.

My car was never converted to R-134a.

If I really needed AC, I'd consider regular (annual?) re-charging with R-134a as a reasonable solution to any loss of refrigerant you get due to an imperfect barrier.

And if I were to go beyond that, I'd get serious and look into some of the more modern AC solutions for these cars.

Skidog214

Good point about the cost. I can understand that one may prefer to re-charge more frequently rather than spend the money for barrier hoses.
And, I went back and looked at the paperwork. I did not see charges that were high enough to include replacement of all the hoses.

Thanks to all for the input!

darylbowden

It's highly unlikely you have barrier hoses. That would have nothing to do (strictly) with an R134 change. Really, the only time you would see barrier hoses is if somebody decided to redo the whole system to try and make it work better. So you'd likely also have a new compressor, condenser, evap, drier, etc.

It's a big job to do just the hoses. As mentioned above, it is common to just recharge once a year - it's far cheaper to do that 20 times than rehabbing the whole system (which will cost you north of 5k easily). It won't work as well, but it'll be passable and that's about as much as you can ask from these cars.

mk85911

I converted to R-134 about a dozen years ago on my 85, but I didn’t bother with the barrier hose replacement. As others have pointed out, periodically refilling is a reasonable, and much cheaper, way to go.

theiceman

some of this is surprising . In Canada you cant just recharge ,, if its bleeding out the mechanic tags and records it as leaking and can not recharge it or he will lose his license. Do these regulations vary by state ? just curious

mk85911

The rules for leaks in a R-12 system may be stricter than leaks in a R-134 system. But I’m not 100% sure of this.

76FJ55

theiceman

interesting , .looks like we are going the same way as im seeing cans of " freon" now in car stores.. but i think you are right about the shop part . licensed HVAC guys are much more controlled.