a - Seawater inlet
b - Seawater pump
c - Power steering fluid cooler
d - Y‑fitting
e - Drain fitting
f - Fuel supply module water inlet strainer
g - Fuel supply module
h - Distribution housing
i - Drain fitting
j - Y‑fitting
k - Water circulating pump
l - To engine block (from water circulating pump)
m - To crossover (from engine block)
n - Crossover with 60° C (140° F) thermostat
o - Exhaust manifold seawater inlet and drain
p - Exhaust and seawater outlet
q - Poppet valve assembly (green)
r - Exhaust elbow seawater inlet (poppet valve closed)
s - Exhaust manifold seawater inlet (poppet valve open)
t - Starboard exhaust manifold drain hose
u - Port exhaust manifold drain hose
v - Starboard engine block drain hose
w - Port engine block drain hose
x - Oil cooler
NOTE: When the poppet valve opens water will flow into (r and s)
Water Flow Diagrams
90-8M0099748 eng DECEMBER 2015 © 2016 Mercury Marine Page 6D-3