IO-390-D Series Engine Maintenance Manual
© 2020 Avco Corporation. All Rights Reserved
05-20
March 2020
Page 17
IO-390-D Series Engine Maintenance Manual
4.
25-Hour Engine Inspection for IO-390-D Series Engines
The purpose of this inspection is to measure the oil level and oil consumption, replace the oil filter or
clean the oil pressure screen, complete an initial oil change, identify and correct the cause of any oil
leak.
A.
Complete this 25-Hour Engine Inspection at the following times:
•
After 25 hours of engine operation or the first 4 months since the engine was placed into
service (whichever comes first) per Chapter 12-10
•
25 hours after one or more new engine cylinders and/or piston rings have been installed
•
If the rate of oil consumption has not stabilized
NOTICE:
Refer to the “Oil Servicing Schedule” in Chapter 12-10.
B.
Copy and complete the 25-hour Engine Inspection Checklist for IO-390-D Series engines as
a record of engine service. Record the engine hours.
WARNING
BEFORE ANY ENGINE INSPECTION OR SERVICE PROCEDURE,
MAKE SURE THE IGNITION SWITCH IS SET TO OFF AND THAT ALL
POWER TO THE ENGINE IS DISCONNECTED. ENSURE ALL
OBJECTS/PERSONNEL ARE CLEAR OF THE PROPELLER’S
ROTATIONAL ARC. IF POWER IS ON, A LOOSE OR BROKEN WIRE
CAN CAUSE THE ENGINE TO START AND THE PROPELLER TO
TURN WHICH CAN LEAD TO DEATH OR SERIOUS INJURY OR A
PROPELLER STRIKE.
25-Hour Engine Inspection Checklist for IO-390-D Series Engines
Engine Model Number___________________
Engine Serial Number:___________________
Engine Time:___________________________
Date Inspection Done:____________________
Inspection done by:______________________________
Inspection Item
Comments
Results/Notes
Done
Complete the Visual Inspection
Checklist in this chapter.
Refer to the section “Visual
Inspection for IO-390-D Series
Engines” in this chapter.
Complete the Operational
Ground Check in Chapter 72-00.
Make sure the engine operates
correctly to specifications.
Measure and record the oil level. Refer to the section “Oil Level
Check” in Chapter 12-10.
Calculate oil consumption.
Refer to the “Oil Consumption “
section in Chapter 12-10
Complete this 25-hour inspection
again until oil consumption
stabilizes.
Complete an initial oil change. Refer to the section "Oil Change
Procedure" in Chapter 12-10.