Manual Single-Point Drain System (Alpha); Boat In The Water - Mercury 350 MAG Manual

Section 6 - Storage
11. 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.
12. Before launching the boat, pull up on the manual release valve. Verify that the green indicators are no longer extended.
Manual Single‑Point Drain System (Alpha)

Boat in the Water

1. Close the seacock (if equipped) or remove and plug the water inlet hose.
2. Rotate the blue handle counterclockwise until it stops (approximately two turns). The red on the handle shaft indicates that
the drain system is open. Do not force the handle as this will create new threads.
3. Immediately remove the blue drain plug from the side of the thermostat housing. This must be removed within 30 seconds to
properly vent the cooling system.
4. Visually verify that water is draining. If water does not drain, remove the blue drain plug from the distribution housing and
drain manually.
a
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a - Green indicators
a
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a
b
b
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a - Blue drain plug
b - Drain location ‑ orange or red
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a - Blue handle
b - Blue drain plug location
90-8M0050539 MAY 2011
eng