CM871 poor power and fuel econ

[Rawze]

(09-24-2022 )Grounded Pilot Wrote:  ...
I ran a air in fuel test when I got home today and it has a bunch of tiny bubbles in it.
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You may or may not have air getting into the fuel.. but Don't chase a ghost ...

The CM570, CM870, CM871 (any of the IFSM engines) return line off the IFSM that go back to the tanks will always have some tiny bubbles in them. It is normal, as there is a small restriction in the main return line + a sudden pipe diameter change, that creates a bit of cavitation. It has no effect whatsoever on engine or its performance, and is quite normal. This has always been known and is NOT in the manuals for some reason.