Operation; Cylinder Block / Cylinder Head Cooling; Vapor Separator, Emm And Battery Charge Module Cooling - BRP Evinrude E-TEC Series Service Manual

OPERATION

All models use a two-stage cooling system
design. The cooling system is dependent on water
pump pressure and controlled by thermostat and
pressure valve operation.
NOTICE
Restricted or inadequate water flow
through the outboard reduces cooling system
performance and may lead to severe power-
head damage.
Cylinder Block / Cylinder Head
Cooling
The flow of water through the cylinder block and
cylinder head is controlled by a thermostat and a
pressure relief valve. The thermostat and pres-
sure valve are located in the top of the cylinder-
head.
1
1. Thermostat
2. Pressure valve assembly
The thermostat and pressure valve control the
flow of water entering the vertical water passages
of the cylinder head.
At low speed, the pressure valve is against the
seat and the thermostat is closed. Warm water
from the cylinder block gradually migrates to the
thermostat pocket at the top of the cylinder head.
The thermostat opens when the water tempera-
ture reaches approximately 143°F (62°C).
When the thermostat opens, water flows down
through the cylinder head to a passage in the cyl-
inder block. Water flows through the block to the
exhaust housing and then out of the outboard.
At higher speeds, water pressure opens the
pressure relief valve at approximately 2800 RPM.
Water flows through the valve to the cylinder head
and bypasses the thermostat. All water flows
through the cylinder head to the outlet passage of
the block and then exits through the exhaust
housing.
Vapor Separator, EMM and Battery
Charge Module Cooling
Cooling water is routed from the exhaust cover to
the inlet fitting of vapor separator water cavity.
Cooling the vapor separator fuel chamber mini-
mizes fuel vaporization.
Cooling water from the vapor separator is routed
to the water inlet fitting of the EMM water cavity.
Cooling of the EMM helps to stabilize the temper-
atures of internal components.
IMPORTANT:
2
vate service codes 25 and 29 and the Engine
Monitor warning system. Refer to the EMM Ser-
vice Code Chart at the back of this manual for
specific service code information.
On rope start models, cooling water from the EMM
is routed to the overboard indicator.
On electric start models, cooling water from the
EMM is routed to the water inlet fitting of the bat-
tery charge module water cavity. Cooling water
from the battery charge module is routed to the
007371
overboard indicator.
1
1. Overboard indicator
COOLING SYSTEM
OPERATION
Improper EMM cooling will acti-
9
007372
161