MerCruiser Sterndrive 4.3 MPI User Manual page 127

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 Cooled Models
8. Verify that water is draining from each opening. If not, use the Three Point Manual
Drain System instructions.
a
9. Allow the system to drain for a minimum of five minutes. Pump air as necessary to keep
the green indicators extended.
10. Crank the engine over slightly with the starter motor to purge any water trapped in the
seawater pump. Do not allow engine to start.
11. Reinstall the blue drain plug in the thermostat housing or heat exchanger.
12. Remove the air pump from the air manifold and return it to the mounting bracket.
13. Mercury MerCruiser recommends leaving the drain system open while transporting the
boat or while performing other maintenance. This helps ensure that all water is drained.
90-864195061 NOVEMBER 2006
c
d
a - Blue drain plug location
b - Blue air pump
a - Port side drain location
a
6124
Seawater Cooled Models
c - Air manifold
d - Green indicators
b
b - Starboard side drain location
Section 6 - Storage
c
b
d
6125
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