Mercury 350 MAG MPI Horizon, Service Manual

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61
CC1024
SINGLE POINT DRAIN SYSTEM
CAUTION
Freeze damage can occur if operating where temperatures are below 32
°
F. Use Manual Drain System
to ensure heat exchanger is completely drained.
NOTE: This procedure is written for the air pump that is attached to the engine. However, any air source can
be used.
1
Remove air pump from engine.
2
Ensure that lever on top of pump is flush with the handle (horizontal).
3
Install air pump on the actuator fitting.
4
Pull lever on air pump up (vertical) to lock pump on actuator fitting.
5
Pump air into the system until both green indicators extend and water drains from both sides of the engine.
6
Most water will drain from the engine in 3-4 minutes, however, some will remain trapped in the heat
exchanger. In order to prevent freeze damage, leave system pressurized while transporting boat or during
other maintenance items to allow the remaining water to drain.
IMPORTANT: Before launching boat, pull up on manual release valve (A). Verify that green indicators
are no longer extended.
CAUTION
Manual release valve may not close completely. Ensure valve is completely seated.
MANUAL DRAIN SYSTEM
NOTE: If air actuated drain system fails, use the blue drain plugs to drain engine.
NOTE: It may be necessary to lift, bend or lower hoses to allow water to drain completely when hoses are
disconnected.
7
Remove blue drain plugs from front and rear of cool fuel cell and from the seawater pump.
8
Remove end caps, sealing washers and gaskets from heat exchangers.
9
Repeatedly clean out drain holes using a stiff piece of wire. Do this until entire system is drained.
10
Remove both hoses from seawater pump.
11
Crank engine over slightly with starter motor to purge any water trapped in seawater pickup pump. DO NOT
ALLOW ENGINE TO START
.