Smg4 gauge mpg?

[Dale15]

I got twin suzuki df140a. I have two smg4 gauges.
I have nema them to my simrad go12. I can find them in device list. I cannot get the. To show mpg, it just shows ----
They will show me gph. Does anyone know what I need to do to get mpg to read correct.

[Murray]

I think the resident expert might want the year of the engines.

[Dale15]

They are 2020

[Dale15]

I finally found a old post. Had to turn water speed off. Now if I can figure out why the main fuel bar up top is correct but if you cycle through the bottom the small fuel bar is way off.

[Moonlighter]

Yes good work finding previous posts on changing the speed source!

As to the fuel tank bars - Im going to kinda pass on that, although it may be to do with fuel tank setup for twin engines?

Here is the gauge installation manual. Have a look in there to see if you can find any clues, and if you do, dont forget to report back with results. Please!

https://www.dropbox.com/s/u2fa08g7nw...glish.pdf?dl=0