my port 700 motor stars losing fuel pressure after if has been running about 30minutes all the down to 20 on smart craft

anyone know the problem

try replacing your fuel filter

the water seperator or the fuel filter at the fuel rail aeromotive type and why is it doing it only when the motor warms up

Had same problem in my 2007 42 fountain w700sci. Try looking at your fuel lines that come from your belly fuel tanks through the bulkhead to fuel switch valves. Mine had a slight cink in it and would reduce fuel pressure. So I ran a new line and it fixed my problem.

Not the fuel line

Changed all fuel filters going for run

If still have problem going to switch to rear tanks and try running it again

OSO Does it again

Changed fuel filters

Last run 104.6

Fuel press perfect

Thank You OSO

Which filter did you change - the water / fuel separator that screws on below the pressure regulator on the front of the engine?