INSTALLATION MANUAL
90-864198020 Page 31 of 77
NOTE: A kit is available to reduce from the 4 in. (102 mm) to 3 in. (76 mm). Refer to the
Mercury Precision Parts / Quicksilver Accessories Guide, for kit part number.
71774
a
b
c
d
e
f
Typical Continuously Sloping Exhaust Line
a-Exhaust Elbow
b-Exhaust Hose Or Pipe
c-Muffler (If Equipped)
d-Exhaust Outlet Internal Shutter
e-Exhaust Flapper Valve
f-Waterline
71775
a
b
c
d
e
f
g
Typical Waterlift Muffler Exhaust System
a-Vent Line [1/4 in. (6 mm)]
b-Transom
c-Water Line
d-Exhaust Hose
e-Drain Fitting
f-Water Lift Muffler
g-Exhaust Elbow
CAUTION
Avoid severe engine damage. A 1/4 in. (6 mm) vent hose must be run from the high-
est point in the seawater system to the exhaust pipe after the water lift muffler to
break the vacuum and prevent water from back-filling the engine.