Fuel Injector Leak Check; Fuel System Inspection Checklist - Lycoming IO-390-D Series Maintenance Manual

IO-390-D Series Engine Maintenance Manual
IO-390-D Series Engine Maintenance Manual

3. Fuel Injector Leak Check

NOTICE: Complete this procedure in the cockpit to examine an installed leaky fuel injector.
A. Disconnect the induction system at the fuel injector inlet to monitor the impact tubes.
B. Put the throttle in the FULL FORWARD position.
C. Put the mixture control in the FULL RICH position.
D. Put a cap on the fuel line to the fuel manifold.
E. Turn ON the fuel boost pump.
F. If fuel flows out of the impact tubes, the fuel injector has an internal leak and must be
replaced with a serviceable unit.
Engine Model:
Inspection Item
Examine the fuel pump for secure
attachment and damage. Replace a
damaged or malfunctioning fuel pump
per the "Fuel Pump Replacement"
procedure in this chapter. Tighten any
loose fasteners.
Examine the fuel injectors for damage,
leaks, and loose fittings or
connections. Tighten any loose fitting
or connection.*
Replace a damaged fuel injector per
the "Fuel Injector Replacement"
procedure in this chapter.
Examine fuel line fittings for damage
or leaks. Unless otherwise stated,
make sure all fuel line fittings and
connections are secure and correctly
torqued.*
If tightening does not correct a fuel
leak, replace the fitting.
* Per the Standard Torque Tables in the latest revision of the Service Table of Limits - SSP-1776.
© 2020 Avco Corporation. All Rights Reserved
March 2020

Fuel System Inspection Checklist

Engine Serial Number:
Fuel Line or
Injection Nozzle
Date of Inspection:
Findings
N/A
1
2
3
4
1
2
3
4
Inspector:
Corrective Action Taken
73-10
Page 259