AC Repair
2001 E-55 112000 miles
I bought this car in October 2014 with 103,000 miles and have all the service records. The AC system never required any service besides the cabin filters.
Last year, spring 2015 I had to add a small amount of R-134A so the system would cool properly.
This year, March 2016, the system did not cool properly. I noticed an oily substance on the top of the pan beneath the compressor and the rest pressure was 4 bar. I topped off the system and it cooled properly for a couple of days and leaked back down to 4 bar.
I verified that all sensors work and aux fans function properly.
I have a vacuum pump, gauge set and R-134a.
Plan
I plan to replace compressor, receiver/dryer/accumulator, expansion valve.
Question
Should I replace the condenser too, or just back flush it?
What are you thoughts.
I have conducted searches and read many threads but I still would like to get constructive feedback from knowledgable members.




Sounds to me that you found the leak source, yet you want to do major replacement.
Something wrong with fixing the leak?
Then yes, if you replace compressor, replacing dryer, where all the dirt collects is highly recommended. Expansion valve might require cleaning, but no replacement necessary.
I took it to a local garage and he replaced the shredder valve(?) that you use to charge the system with on the low side for free. He said he remembered it was laying around somewhere in his shop. No problem since then. What a nice guy... You never know it could just be a simple thing.
So, I asked for an oil change from him on top of the basic system recharge he had to perform.




I think you are overthinking the issue.
First you want to replace compressor where there is no indication anything is wrong with the old one.
Than you want to flush the system, while you are still using the same refrigerant?
Flush is needed when you convert the system from one refrigerant to other.
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Compressors seals can be replaced, but I agree that this is not really DIY, but still double check it is compressor that leaks, not 25 cents oring on fitting.
What is the proper oil and quantity for the compressor ?




Now back to business. You have no way to measure how much oil you lost, so you have to use your best judgement.
The oil makes huge stains from few drops, so it easy to overestimate.
I would put 50% of recommended amount. You should find "oil charge" with R134 (for easy application) on the shelf.
Is your drier having inspection glass on it?
Last edited by kajtek1; Apr 6, 2016 at 06:13 PM.
Now back to business. You have no way to measure how much oil you lost, so you have to use your best judgement.
The oil makes huge stains from few drops, so it easy to overestimate.
I would put 50% of recommended amount. You should find "oil charge" with R134 (for easy application) on the shelf.
Is your drier having inspection glass on it?
Can't tell from the picture if the drier has an inspection glass.
Parts will arrive n a few days.
I'll add a bit of oil to the system before startup.
Thanks for the info.




Most of AC oil accumulate in drier, so since you are replacing it with defective hose, you need to add close to 100% of oil capacity.
My experience it's good to get all the old **** out with the evac - which also serves to test all connections are good..
For me, if the compressor is "precharged" or "pre-oiled" personally I don't add oil... but that's just me..



