DIY project: Adding a fuel consumption data to older diesel

[Waterant]

I have also looked into adding a fuel flow meter to my 80 hp Ford Lehman...

It may work for a small engine - there are very nice and industrial grade flow meters available which will show you the flow rate in one direction.

for something like 6LY yanmar, the return rate is almost equal the intake and goes to 250+ L/h on both lines. Checking only intake flow is pointless - you need to see the difference.

Another challenge is to feed that dat into nmea for a chartplotter to calculate other fuel rate related numbers.

 

[Marco Flamingo]

one for something like 6LY yanmar, the return rate is almost equal the intake and goes to 250+ L/h on both lines. Checking only intake flow is pointless - you need to see the difference.

Another challenge is to feed that dat into nmea for a chartplotter to calculate other fuel rate related numbers.

Digiflow make models up to hundreds of gallons per hour, presumably enough for a 6YL. One would temporarily install one on the intake ($50) and one for the return ($50). Make a graph and remove them (the fewer connectors on the fuel lines the better). If any need for "related numbers" in the future, do the math. Use the savings to buy a new outboard for the tender.

What am I missing about needing more flashing numbers on an MDF?

 

[Waterant]

Make a graph and remove them (the fewer connectors on the fuel lines the better). If any need for "related numbers" in the future, do the math. Use the savings to buy a new outboard for the tender.

What am I missing about needing more flashing numbers on an MDF?

You can easily do the same with no modifications at all. Just fill the full tanks and fill up again after a few hours run to the next destination at the constant speed.
3-4 runs like that will give you reference points for your consumption graph.

I just like to see flashing numbers on MDF and get the instant data.