I've recently made a chiller with the following:

~6k BTU rotary "Rechi 39r131f"
r507/404a TXV
4x120mm 2000RPM fans on condenser
SLHX
propane as refrigerant
Filter/drier
Homemade receiver

The problem I'm having is that my compressor gets extremely hot. Once the evaporator starts cooling off a bit, meaning that the restriction in the loop rises, the compressor gets quite quickly to very hot temps (80c+) I THINK that this is because there is far less oil flowing through the loop anymore, meaning that the compressor doesn't get the proper oil return. I have tried even putting a 250CFM leafblower-like fan on the compressor, and still it gets very hot, leading me to believe that there is not enough oil in the system. Oil may have escaped quite a bit when I did 10+ leak tests with propane when building my system.

To have my system run safely, I've lowered the TXV restriction quite a bit, so that (in theory) it is getting more oil flow. The downside to this temporary fix is that my temps are very high (7c or so in the PC coolant loop)

One time I left the system with the TXV turned to max restriction, with the 250 CFM fan on there. When I got back, the compressor was at 110c

Would you guys confirm that too little oil is indeed my problem? Is there any way to just add some via a schrader valve?

Thanks,
Eli