Yes it is difficult to get the right expansion valve.
The reciever drier should be replaced when the system is open.
While you wait for parts, flush the condenser. The bottom of the condenser collects crud/thick oil. Flushing with protect your new expansion valve. Parts stores have a pressurized can of flush to use. .
THEN...
Add an ounce of POE 100 esther oil to the receiver drier.
Add a couple of ounces of POE 100 directly to the inlet of the condenser.
Add one ounce of POE 100 oil to the inlet of the evaporator.
POE 100 mixes with the original AC oil best.
PRO AC tech/shop owner Griffiths explains:
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J_AZ