Mercury Mercruiser Tow Sport 5.7 MPI Manual page 70

Section 6 - Storage
5. Pull the lever on the air pump (vertical) to lock the pump on the fitting.
c
b
6. Pump air into the system until both green indicators extend and water drains from both sides of the engine. The port side
will begin draining before the starboard side.
7. Immediately remove the blue drain plug from the side of the thermostat housing or the heat exchanger. This must be
removed within 30 seconds to properly vent the cooling system.
a
b
Closed cooling models
a - Blue drain plug location
b - Blue air pump
c - Air manifold
d - Green indicators
d
Page 62
e
a
c
d
a
b
a -
b -
c -
c
d -
d
21125
d
8293
a
6124
Seawater cooled models
Scorpion models
Blue air pump
Air manifold
Green indicators
Blue drain plug locations
a - Actuator fitting
b - Green indicators
c - Manual release valve
d - Air pump
e - Lever (locking)
c
6125
90-8M0076545 NOVEMBER 2012
eng
b
d