Hey guys!

It's been a while since my C5 has gotten some attention, last year the A/C compressor seized up and made the belt eventually snap. Been driving without A/C for some time now, and now I'm looking to tackle this job myself, I have NO experience with working on A/C systems.

The parts that I have bought for the job:
1 x FOUR SEASONS 5371NK - A/C Compressor & Component Kit (Includes all o-rings/seals, orifice tube, service valves and caps and accumulator)
1 x APDI/PRO 7014786 - A/C Condenser
2x GM GENUINE 251663 - Water Pump Gaskets (After doing some research I found that my 1998 C5 comes with old paper gaskets, and these new metal gaskets with rubber inserts is a better option)
1x VICTOR REINZ 411041500

What I need help with:
I will be getting the A/C system discharged by a shop before starting with this job. I will then proceed with the whole disassembly process. Now I have no problems unbolting and bolting on new stuff. But I'm wondering if there is something specific I should do regarding "flushing"/cleaning the A/C system for debris? Anyone with some good tips here would be very appreciated, as I've understood it is quite crucial to replace the condenser aswell, as it can't be flushed because the C5 comes with a parallel flow condenser, and the fins is very small?
And my next question is about adding oil to the system. The compressor comes prefilled with OE specified oil, the kit I have includes oil aswell. Do I have to add more oil to the system, or will I be fine with the oil in the compressor, and letting a shop do the recharging of the system?

I have all the time in the world to tackle this job, so I wanna make sure I do it correct, every answer is highly appreciated!

 

You should empty the compressor when it arrives, to see exactly how much oil is in it. If I recall, the system takes 8-9 ounces of refrigerant oil total. Since you're replacing multiple components, you can divide that amount up across the different components, though in a recent thread here, someone mentioned that on the assembly line, the oil was all in the compressor and the rest of the system was empty prior to charging.

There is a specific flush solvent you can buy, with a rubber nozzle to mate up to the evaporator housing and the lines. Brake Cleaner works too.

I agree you should replace the condenser, and the accumulator (also called receiver / dryer).

 

Here's a great writeup I saved

 

I did this last week, after the old parts including the condenser were removed, the remaining tubes and evaporator were flushed. The new compressor was shipped with 46 PAG oil and that was drained then 5 oz of 150 PAG oil was added to it and 4 oz to the new receiver/dryer since the system had no oil after flushing. The directions with the new compressor explained how to drain the old oil by removing the drain plug. The first can of refrigerant went in slow because the compressor clutch wouldn't turn on but after resting overnight the next day the pressures were up to 35 pounds and equalized so the clutch engaged to add the second can. The discharge air temperatures weren't very low until the next day when adding 2 more ounces of refrigerant as if the system needed to equalize again. Now the discharge air temperature is cold. One thing that was added last year was a digital temperature meter to the ashtray with the sensor in the discharge airflow out of the center duct. The meter was $9 from Amazon (Uctronics 0-167 F) and provides a nice check on the system performance while driving.