An interesting thing about the Yanmar 2QM series is that there is no return
line back to the tank. Evidently, the injector bypass just circulates back
as far as the injector pump on the engine. It is an unusually cool running
engine for a diesel so maybe that helps avoid the fuel getting too hot.
Flow through the filter is whatever fuel consumption is.
Just out of curiosity, I'm going to look at recommended flow rates on some
separator filters but I'll be surprised if any
go as low as 1 gph. It's appears to be a centrifugal process judging by the
spiral grooves I see on some of the filter housings so it must take a
reasonable flow. Just out of curiosity, I'm going to look at recommended
flow rates on some separator filters but I'll be surprised if any go that
low.

Chris had a good point, now that I'm putting an emulsifier
(StarTron/Soltron) in the fuel, The water isn't going to separate out
anyway.

--
Roger Long