IO-390-D Series Engine Maintenance Manual
© 2020 Avco Corporation. All Rights Reserved
05-30
March 2020
Page 45
IO-390-D Series Engine Maintenance Manual
B.
Use any of the following cleaning methods as long as it is not harmful to the component or its
intended function:
•
Vapor degreasing
•
Solvent degreasing
•
Ultrasonic cleaning
•
Chemical cleaning
•
Aqueous-based cleaning
•
Mechanical cleaning (such as grit-blasting)
NOTICE:
Grit blasting without etching can be an acceptable cleaning method if it can be
demonstrated that a sufficiently fine abrasive (150 grit or finer) will not cause
peening and can be removed by a detergent or alkaline cleaner.
Etching of the area(s) to be examined is to be done prior to inspection when
evidence exists that previous cleaning, surface treatments, or service usage has
produced a surface condition that degrades the effectiveness of the penetrant
examination.
