Well done on getting the thing undone- beggars belief that they should install something like that but there you are- no shortage of quirky things on the 928!

The bit about the barrier hoses is somewhat misunderstood- you would not want to put in a new hose that was not of the barrier type however, hoses that have been in R12 service with mineral oil ironically absorb some oil and that is turn in acts like a barrier to stop the R13a escaping or at least that is what a trusted friend of mine advised and why I have not sweated too much over that short length of captive hose on the filter dryer outlet.

If you do not have the correct O rings then you really should change out the wrong ones- it does not take that long to do so - just remember to do the ones on the instrumentation as well.

 

Thanks for the encouragement Fred.

I too have heard that the old hoses soak up the oil and are somewhat effective in containing the R134a. After reconsidering a bit, I went ahead and ordered some new hoses though. My thinking was not so much for the barrier protection but that the hoses are 30+ years old and so difficult to get to, it may be time for replacement anyway. What's another $300 amortized over the last 30 years plus another 30? It's thinking like that that got me into this mess.

I started this part of the project with the intent to just replace the o-rings but mission creep got the best of me. So its now o-rings, compressor, hoses, drier, a flush, expansion valves and on and on. Not to say of the refurbing the heater box and fresh air box with diaphragms, foam and all manner of other things inside the car.

But what is the instrumentation you refer to with regard to the o-rings?

 

Again, not sure of your model configuration but presume it will be similar- my model has a pressure sender and a pressure switch on the condenser outlet manifold and both have O rings- easy to forget about them as they do not need to be disturbed but they can leak just like anything else. The good thing is the sender can be removed with the system gassed up- there is a schrader valve in there- I think it is the same for the low pressure switch as well- my memory is getting faded- either age, covid or both?

As with other aspects on this thing the ac system is something you really should go through once and then leave it for another 20 years

 

Oh, right. I've got those covered. Those are what led to my having to remove the condensor. And loosen the radiator.

 

If you have loosened the condenser be careful when re-tightening- those bolts underneath have been known to go through the condenser tubing- probably because some dork put the wrong bolt back in but just be mindful.

Do you have the rear ac package?

 

Yes, I have rear air as well. I have already completed the maintenance on that, replaced the expansion valve, leak checked the evaporator, changed the o rings, flushed the hoses including those under that passenger seat and under the car. AC maintenance is a BIG job in this car!