Evinrude E-tec 75 HP, Service Manual, Page: 183 / 344

183
OILING SYSTEM
COMPONENTS
8
Oil Recirculation System
External hoses and fittings, internal cylin-
der/crankcase passages, and intake manifold pas-
sages are used to “recirculate” any accumulation
of oil from various locations in the powerhead.
The movement of oil in these “oil circuits” is con-
trolled by check valves.
Cylinder Recirculation
Internal powerhead oil drain passages connect
the intake port areas of the cylinders to circulate
residual oil in the block.
External fittings and in-line check valves on each
side of the cylinder block control the movement of
oil from the lower cylinder port to the upper cylin-
der port.
Crankcase / Main Bearing Recirculation
The movement of oil through the upper main bear-
ing, center main bearing(s), and lower main bear-
ing is provided through internal powerhead oil
drain passages, external fittings, and external in-
line check valve(s) and hoses.
Lower to upper main bearing oil flow:
•
Lower main bearing cavity to internal crankcase
passage to external fitting, external hoses with
in-line check valve to external fitting at upper
main bearing, and into upper main bearing
through internal crankcase passage.
•
Internal crankcase passage to external fitting in
crankcase cover at upper main bearing, hose
routed to reed plate fitting. This circuit vents the
upper main bearing cavity to promote oil flow.
Refer to the Recirculation Hose Diagram .
Recirculation Hose Diagram
75 – 90 HP M
ODELS
1. Upper main bearing vent
002872
1
002223
Starboard view
Port view