Evaporator Core
Thank you for your response and for the A/C info. This is my first time attempting any AC repair/service. I am not sure if the dryer has ever been changed in my 1999 Beetle. I have had it charged once tthat I can remember since I have owned it in 12 years. And that was after it broke last year.
I would love to see the Bentley information. I did purchase the Bentley CD from Amazon. It is supposed to be a new copy but was used and I could not activate it. Amazon will send me another one but will probably be another week or two. I am already day 14 with my car on jack stands. The NB Haines manual is not too bad (it jumps around alot), I was able to figure out how to pull the dash apart. But there is nothing about the evaporator core.
I am at a standstill with the evaporator core, as I am not sure if I can or should remove the lines or not. I do not want to aggravate the situation by adding chemicals "flushing" the core if I am not susposed to. Do the two lines from the expansion valve through the firewall go in and out of the evaporator core as a closed circuit? Can I just flush at the firewall opening and not worry about damaging the evaporator core or disconnecting the lines? I do not plan to replace the core if it is not necessary, so is there any reason to try and access it from under the dash? The desiccant pellets are very hard, I hope that they stopped at the expansion valve, as the opening is physically too small for them to travel through the valve to the evaporator core.
I am replacing the discharge hose, compressor, dryer and expansion valve. I have a bag of new o rings. I already have a shop air compressor, and bought a new vacuum pump and AC gauge set. I plan to use compressed air on each part separately, including the condensor, then flush each section until clear with a spray chemical I bought at auto zone (see photo).
My original VW compressor had no oil come out of it even when turning the clutch. I added about 3.5 ounces to the new compressor, which is all I could force into it, even with turning the clutch. The new compressor had a few tablespoons of oil in it, and the directions said to empty it and replace with the same amount in the old compressor. Just from looking on line it seems like about 4 ounces was a standard recommendation, no recommendation in NB Haines Manual.
I added 13.5 ml of oil to the dryer (I read those instructions somewhere). I did not add any dye to the system, I think I will buy some and add it before it goes back together, I should have room for about 0.5 ounces, I guess I can just add it into the new discharge hose.
I plan to pull a vacuum on the system when it is assembled. And take it to a service center to charge the system and look it over when I am done. Especially since it is my first repair.
I found the low pressure access on the front passenger side of the car, above the radiator. Where is the High Pressure access? Passenger side, close to fender, back by expansion valve? (see photos)