1989 740

I am converting and replacing my old Diesel-Kiki w/ a Sanden 709 (I was told it's much more efficient).

I was reading the FAQs, and it said that if I flush the FLEXIBLE LINES, I will remove the protective "barrier" created by old mineral oil in R-12, and they will leak R-134 (as will OEM stock replacements for my car since they are intended for R-12).

Therefore, would I be correct in assuming that I should disconnect all lines, but ONLY flush the solid components (Evaporator, Condenser, Solid (non-flex) Lines), and perhaps only blow out the flex lines w/ air?

I plan to replace all O-Rings, and they recommend Nitrile? Is this the best for R-134 and the Ester replacement oil?

Thanks,
Bob

Others will know more, but I do know that the problem with R134 is that it's a smaller molecule so it leaks more easily.
I have a converted 91, and after about 7 years it is low on charge. That is not too bad. But I am considering going to the EnviroSafe, for this car and my others.

HA!

I don't even know what Enviro-Safe is.

I read one report where a person who used BRAND NEW OEM hoses w/ R134 with dye check w/ it said his hoses glowed yellow/green w/ a UV light because so much leaked through the hoses. He also claimed that if you clean the microscopic mineral oil "coating" off old hoses they will leak, but that if you don't, they are impervious to R134.

You should replace all of the rubber hoses with new. That rubber has a finite life and new hoses will be barrier hose. If there's a hydraulic shop where you live, take them there and they can replace the rubber and crimp on new ferrules on the junctions. Personally, I think that mineral oil sealing the hoses bit is BS.

We have tractor repair shops that rebuild hydraulic hoses.

I wonder if they have R-134 barrier hose available?

No A/C hose repair shops around here, unfortunately.

I guess I could buy hose via mail ( http://www.acsource.com/hoseacbarrier.aspx ) or ( http://www.acsource.com/hoserepair.aspx )and take the components to them to have it installed on my old hardlines (assuming they have crimpers for the ferrules?