Fuel Injector - Mercury 25 EFI Service Manual

Fuel Injector

The fuel injector is an electrically operated spring‑loaded solenoid, which delivers a metered amount of fuel into the intake
manifold runner, just ahead of the intake valve. The injectors are electrically charged by the ECM through the stator assembly
when the flywheel starts to rotate. The ECM controls the injection by completing the ground circuit, lifting the solenoid, which
allows high‑pressure fuel to flow through the fuel injector. The ECM then opens the ground circuit, allowing the spring to close
the injector, and stop the fuel flow. An injector filter is located on the fuel inlet side of the injector. The filter is not replaceable,
but can be cleaned of debris.
90-8M0105568 eng MARCH 2016
21100
© 2016 Mercury Marine
Fuel System Operation
Page 3A-7