FUEL INJECTOR ASSEMBLY REPLACEMENT - CONTINUED
TESTING - CONTINUED
Back Leakage Test
WARN I N G
Ensure eye protection is worn at all times during testing. When fuel injector nozzles are tested, test
fluid travels through orifices of nozzle tips at high pressure. Under this amount of pressure, test fluid
can pierce skin and cause injury to personnel. Always keep tip of fuel injector nozzle pointed away
from personnel and into fuel collector and extension. Failure to follow this warning may result in
injury to personnel.
Connect fuel injector nozzle (2) to tooling as shown.
Position fuel injector nozzle (2) so that fuel spray is
directed into coupling and can.
Pump pressure to 3,525 ± 50 psi (24,304 ± 340 kPa).
Release handle. When pressure begins to decrease,
note time required for pressure to decrease to approxi-
mately 0 psi (0 kPa). If fuel injector nozzle (2) is not
faulty, time will not be less than 5 seconds or more
than 45 seconds.
Look for any leakage. If leaks are visible, make sure that components are tightened to correct torque. Replace fuel injec-
tor nozzle if there is excessive fuel leakage.
N OT E
DO NOT overtighten components in order to stop leakage. Instead, a pressure test on fuel injector
nozzle must be conducted. Repeat Pressure Test procedure in this work package. This test may force
any foreign particles out of nozzle.
If pressure decreases to 0 psi (0 kPa) in less than 5 seconds, too much fuel is leaking around valve needle. Valve needle
or fuel injector nozzle must be replaced to correct problem.