2007 Evinrude E-Tec 75, 90 HP outboards Service Manual, Page 165Get this manual
FUEL SYSTEM FUEL COMPONENT TESTS
Fuel Supply
Fuel System Pressure Test
Relieve fuel system pressureSee Relieving Fuel System Pressure on p168
Relieve fuel system pressure before removing fuel pressure gaugeSee Relieving Fuel System Pressure on p168Results: Normal pressure Observe pressure reading after outboard is shut OFF Proceed to Lift Pump Pressure Test on p166Pressure drops after outboard shut OFF Leaking fuel injector Leaking pressure regulator External fuel system leak High pressure Suspect damaged pressure regulator in vapor separator, restricted fuel return manifold, or vapor separator fittingLow pressure Check fuel supply to fuel lift pumpRefer to Lift Pump Vacuum Test on p167Higher vacuum readings indicate restrictions in the fuel supplyRepair or replace as needed Lift pump not supplying adequate fuel to vapor separatorRefer to Lift Pump Pressure Test on p166 If the above requirements are met and vapor separator remains full of fuel, suspect damaged circulation pumpReplace vapor separator assemblyNo pressure Check electrical circuit and ground connections for circulation pump Voltage present and pump does not runRepair connection or replace vapor separator assembly