IO-390-D Series Engine Maintenance Manual
72-20
© 2020 Avco Corporation. All Rights Reserved
Page 168
March 2020
IO-390-D Series Engine Maintenance Manual
(1)
Clean and lightly coat the lifter parts with
engine oil before assembly.
(2)
To assemble the unit, unseat the ball (Figure
64) by inserting a thin clean bronze wire
through the oil inlet hole.
(3)
With the ball off its seat, insert the plunger
and turn it clockwise until the spring engages.
Figure 64
Hydraulic Lifter
B.
Tappet Installation
NOTICE
During maintenance, complete a visual inspection of roller tappets for integrity and
free rotation of the roller action as acceptable to return an in-use roller tappet to
service. However, during engine overhaul or in the event the engine is disassembled
for a propeller strike or sudden engine stoppage, replace all eight roller tappets.
(1)
If the engine operation time is close to TBO, replace all of the roller tappets as a complete
set with a new set of roller tappets. Otherwise, install the same serviceable roller tappets
in the same location.
(2)
Before installation, apply lubrication to the roller tappets per the latest revision of Service
Instruction Nos. SI-1011, SI-1059, and SI-1514.
(3)
Install four serviceable hydraulic roller tappets in each crankcase half during assembly.
(4)
Lubricate the camshaft lobes and the faces of the roller tappets (Figure 63) per the latest
revision of Service Instruction No. SI-1059.
19.
Crankshaft Bearing and O-Ring Installation
NOTICE:
The crankshaft front bearings are
installed on the crankshaft, not in
the crankcase halves. Refer to the
“Crankshaft Installation”
procedure in this chapter.
NOTICE:
If O-ring holes have a countersink,
apply Lubriko M-6 grease to the
countersink before installing the O-
rings.
A.
Install the center and rear crankshaft
bearings. Make sure the tangs are seated
in the lock slots (Figures 65 and 66).
Figure 65
Main Bearing Tang
B.
Apply engine oil to eight new O-rings.
C.
Install the new O-rings in the crankcase
(Figure 66).
Figure 66
Main Bearings and O-Rings
