Automotive Air Conditioning Information Forum (Archives)

ColdZ on Thu September 13, 2012 1:29 PM

Year: 1992
Make: Nissan
Model: 300ZX
Engine Size: 3.0
Refrigerant Type: r134a
Country of Origin: United States

I just overhauled my complete AC system with new parts purchased from AMA (new o-rings, drier, condenser, expansion valve, hi/low binary switch, ester oil), a complete flush, and recharge. The AC blows cold but now the compressor is leaking from the shaft seal and between where the compressor casing meets.

1) I'm going to replace the compressor with a rebuilt one. Will I have to change out this brand new drier because I'm opening up the system again and it might absorb too much moisture in doing so?

2) Also, I will have to refill the system with oil again and can't measure what has leaked out. Is only way to get the right amount of oil in the system is to flush the entire thing again and refill? Any tips or suggestions for this part?

Thanks in advance for any info given.

Edited: Thu September 13, 2012 at 1:48 PM by ColdZ

Cussboy on Thu September 13, 2012 3:22 PM

Quote
Originally posted by: ColdZ
I just overhauled my complete AC system with new parts purchased from AMA (new o-rings, drier, condenser, expansion valve, hi/low binary switch, ester oil), a complete flush, and recharge. The AC blows cold but now the compressor is leaking from the shaft seal and between where the compressor casing meets.

1) I'm going to replace the compressor with a rebuilt one. Will I have to change out this brand new drier because I'm opening up the system again and it might absorb too much moisture in doing so?

2) Also, I will have to refill the system with oil again and can't measure what has leaked out. Is only way to get the right amount of oil in the system is to flush the entire thing again and refill? Any tips or suggestions for this part?



Those are GREAT questions. Disclaimer: I'm not an AC professional, but I do have some knowledge, so wait for a pro to respond.

My opinion - if it was my vehicle:
1. Just use the existing drier if there still is some refrigerant pressure in the system. Do the R&R in a timely manner, so the system is not open to the atmosphere any longer than necessary. And don't do this on a humid or rainy day. If there's zero refrigerant pressure, then some air would have leaked in, bringing moisture, so depends on "how long".

2. I would add the amount of oil that comes out of the existing compressor (measure it) plus like 2 ounces. Others may differ in their opinions.

ColdZ on Thu September 13, 2012 3:39 PM

Thanks for the tips Cussboy. There is definitely a lot of refrigerant left in the system so I guess that means no moisture went in, just pressure pushing out then. The AC is still very cold just like the day I charged it. I do try to use it sparingly in this summer heat after discovering the leak too.

My guess was also around 1.5oz-2oz having leaked out as well. Just an estimate based on the size of the pool discovered in my garage multiplied by the the amount of days and spilling an ounce of oil on purpose to see how much area it covered

ColdZ on Wed September 19, 2012 3:13 PM

Just a follow up. I picked up a compressor last Friday and rented a vacuum from Autozone the same day. I removed the old compressor, and measured how much oil drained out of it. Then I drained what was in the rebuilt compressor and replaced back what I removed from the old compressor plus 2oz. I then put everything back together and pulled vacuum right away, charged it up and all is well again. It feels good to have an AC system that has been completely overhauled