Emm And Vapor Separator Cooling - BRP E250DHLSCS Service Manual

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 1800 RPM.
Water flows through the valve and bypasses the
thermostats. Hoses route the water flow from the
pressure valve to the vertical water passages
below the thermostats. All water flows through the
cylinder heads to the outlet passages of the block
and then exits through the adapter housing.
This pressure controlled water outlet circuit pro-
vides a "high flow" discharge of water during high
speed operation.
This cooling system configuration provides "bal-
anced cooling" at higher RPM by using one pres-
sure valve to control the discharge of water
through both cylinder heads.
Additional Cooling
Two external water supply hoses direct water flow
into the exhaust (plenum) area of the cylinder
block. The water reduces exhaust runner temper-
atures and circulates through the cylinder block.
The base gasket limits water flow to the base of
the block and diverts water flow to the rear port
and rear starboard fittings of the adapter housing.
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1. External water supply hoses
2. Exhaust (plenum)
EMM and Vapor Separator
Cooling
Cooling water is routed from the top of the cylinder
block to the inlet fitting of the EMM water cavity.
Cooling of the EMM helps to stabilize the temper-
atures of internal components.
IMPORTANT:
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.
Cooling water from the EMM is routed to the water
inlet fitting of the vapor separator water cavity.
Cooling the vapor separator fuel chamber mini-
mizes fuel vaporization.
Cooling water from the vapor separator is routed
to the adapter/exhaust housing.
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1
000698r
COOLING SYSTEM
OPERATION
Improper EMM cooling will acti-
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