Draining The Seawater System; Drain System Identification; Air Actuated Single Point Drain System - MerCruiser 5.7 MPI User Manual

Section 6 - Storage

Draining the Seawater System

Water can enter the bilge when the drain system is open, damaging the engine or causing
the boat to sink. Remove the boat from the water or close the seacock, disconnect and
plug the seawater inlet hose, and ensure the bilge pump is operational before draining.
Do not operate the engine with the drain system open.
IMPORTANT: Only drain the seawater section of the closed‑cooling system.
IMPORTANT: The boat must be as level as possible to ensure complete draining of the
cooling system.
Your power package is equipped with a drain system. Refer to Drain System
Identification to determine which instructions apply to your power package.
IMPORTANT: The engine must not be operating at any point during the draining procedure.
IMPORTANT: Mercury MerCruiser requires that propylene glycol antifreeze, mixed to the
manufacturer's instructions, be used in the seawater section of the cooling system for
freezing temperatures or extended storage. Make sure that the propylene glycol antifreeze
contains a rust inhibitor and is recommended for use in marine engines. Be certain to follow
the propylene glycol manufacturer's recommendations.

Drain System Identification

AIR ACTUATED SINGLE POINT DRAIN SYSTEM

a
b
Closed Cooled Models
Page 76
c
d
a - Blue drain plug location
b - Blue air pump
CAUTION
!
a
6124
Seawater Cooled Models
c - Air manifold
d - Green indicators
90-864197072 NOVEMBER 2007
c
b
d
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