
FUEL INJECTORS
SERVICE MANUAL NUMBER 22
Page 5C-12
90-860074--1 FEBRUARY 2002
Inspection
1. Remove any injector seals that may have stayed in the head. Do NOT gouge or nick
seat.
2. Ensure that cylinder head injector bores are clean.
Testing
WARNING
Test fluid from the injection nozzle tester will spray out under great pressure. It can
easily puncture a person’s skin. Keep your hands away from the injection nozzle
tester at all times.
Mercury MerCruiser recommends using the EFEP60H nozzle tester from the Robert Bosch
Corporation. Follow instructions with injector tester for checking nozzle opening pressure
and spray pattern.
IMPORTANT: Mercury Marine does not recommend fuel injectors be disassembled for
service. If an injector tester is not available, substitute a new injector for any injectors
thought to be faulty.
74442
EFEP60H Nozzle Tester
1. Put on safety glasses.
2. Use a nozzle tester to check the injection nozzle opening pressure and the spray
condition.
Description
Specifications
Opening Pressure
27,000 kPa (3915 psi)
3. If the opening pressure is above or below the specified value, the injector must be
replaced or reconditioned.
4. If the spray condition is bad, the injector must be replaced or reconditioned.
77719
a
c
b
a -
Correct
b -
Incorrect (Restrictions In Orifices)
c -
Incorrect (Dripping)