Cylinder Assembly Inspection - Lycoming IO-390-D Series Maintenance Manual

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

9. Cylinder Assembly Inspection

Copy and complete the Cylinder Assembly Inspection Checklist.
Engine Model Number:__________________Engine Serial Number:_____________________
Engine Hours: ___________________________Inspection Date:_________________________
Item to Examine and Corrective
Action
Look for wear or broken parts in the
area of the valve, springs, and spring
seats.
Corrective Action:
Replace the cylinder or send the engine
cylinder to an authorized vendor to
replace all loose, scored, pitted,
defective, or damaged valve seats
(Figure 15).
Examine the intake and exhaust valve
seats for looseness, scoring, pitting
damage or non-conformities. Look for
cracked or eroded valve seat bores.
Corrective Action:
Replace the cylinder or send the engine
cylinder to an authorized vendor to
replace the valve seats.
Examine intake and exhaust valve
guides for looseness, cracks or scoring.
Corrective Action:
If the valve guide is loose, scored,
pitted, defective, or damaged, replace
the cylinder or send the cylinder to an
authorized vendor who can replace the
valve guide.
Look for rust/pitting on:
• Cylinder barrel fins and fin tips in
power stroke areas
• Cylinder barrel and base flange
Corrective Action:
Replace the cylinder if rust/pitting is
found
Do not grind the cylinder bore to
remove pitting or damage caused by
overheating.
© 2020 Avco Corporation. All Rights Reserved
March 2020
Cylinder Assembly Inspection Checklist
Cylinder
No.
Cylinder 1
Cylinder 2
Cylinder 3
Cylinder 4
Cylinder 1
Cylinder 2
Cylinder 3
Cylinder 4
Cylinder 1
Cylinder 2
Cylinder 3
Cylinder 4
Cylinder 1
Cylinder 2
Cylinder 3
Cylinder 4
Findings / Corrective Action
72-30
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