Machine shop forgot oil plug?

See if you can blow air pressure back from the oil filter feed port to the rear main galley.

See if it feels like there is enough flow there to supply full oil flow to the rest of the engine. (and you do not want the air pressure test exiting up through the oil pressure sending unit hole at the same time)

If not your machine shop can easily drill out whatever plug is in there .570ths drill hole, and properly plug it to the proper depth with the replacement stamped steel plug.

Good Luck with your project.

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