Merc 250 Optimax Fuel Flow Sequence - no fuel to injectors

[vigalass]

Gents- need a bit of help. No fuel to the injectors. The pickup pump is spitting fuel fine. The high and low pressure pumps bench tested under 12v fine. When VST is back together in the boat i get no fuel going to the fuel rails. What is the sequence of fuel?... example. Lift pump, to water fuel filter, to high pressure, to low pressure.?

This will help me pull lines and see where the failure resides. Thanks.
Thanks

 

[Tim75]

What is the fuel system pressure? That is the next step. I am not very familiar w. Opti's, but I know FI engines don't run w/o fuel pressure. There is a requirement for air pressure, too. If your high pressure pump runs, but no pressure, check the polarity to the pump.

Best to refer to service book for flow diagram.

 

[dblackstone]

have you checked the 5 amp fuse near the VST