Intake Valve Replacement - Lycoming IO-390-D Series Maintenance Manual

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

13. Intake Valve Replacement

A. Intake Valve Removal
(1) Remove the cylinder from the engine per the "Cylinder Removal" procedure in this
chapter.
(2) Compress the intake valve springs with a Valve Spring Compressor Tool (ST-25) and
remove the valve stem keys (Figure 23).
(3) Remove the valve spring seats and valve springs from the intake valve.
NOTICE: Use care not to scratch the inside of the cylinder barrel when removing the
intake valve.
(4) Remove the intake valve from the valve guide, through the cylinder barrel.
B. Intake Valve Installation
NOTICE: Use care not to scratch the inside of the cylinder barrel when installing the intake
valve (Figure 23).
(1) Apply a coating of Castrol
lubricant identified in the latest revision of Service Instruction No. SI-1059.)
© 2020 Avco Corporation. All Rights Reserved
March 2020
Figure 23
Intake and Exhaust Valves
®
Contractor Special NLGI#1 to the intake valve stem (or other
72-30
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