Fuel flow transducer rotax return fuel

[KenLeonard]

Reading the couple threads on transducers, others have asked the same question but I don’t see clear answer…
Do I need a second fuel flow transducer for my rotax 914 and the HdX? Just getting ready to order all the avionics.

 

[Dynon]

Yes. The 914 has a fuel loop that sends some fuel to the engine, and has a return line that returns the remainder to the tank. If you don't subtract out that return, you'll see incorrectly high (and very high) fuel flow readings. SkyView Installation manual, page 7-60, has a diagram that shows the usual setup.