Here is another item to check. If your fuel lines between the tank intakes and the fuel pump are made of rubber hose, the hose can collapse with aging and restrict flow.
Hi Will, day tanks have almost disappeared completely from boats. Wonder why?
You have two things to solve: 1) The calibration of your horizontal tank volume converted to the use a dipstick and 2) your quest for knowing the engine diesel consumption per hour at different rpm.
There are...