Mercury MerCruiser Service Manual page 461

a - Heat exchanger with attached thermostat housing
b - Crossover
c - Water circulating pump
d - To engine block—from water circulating pump
e - To crossover (from engine block)
f - Exhaust manifold coolant inlet
g - Exhaust manifold coolant outlet
90-8M0099748 eng DECEMBER 2015
h - Detail of rear of heat exchanger, showing thermostat
(shaded)
NOTE: Seawater hoses are not shown, for clarity.
NOTE: TowSport reverse V‑Drive FWC is the same as
the Inboard In‑line fresh water cooled (FWC) except on
the seawater circuit. There is an inlet hose to the sea
pump, and the transmission cooler oil lines are different.
© 2016 Mercury Marine
Water Flow Diagrams
Page 6D-13