Mercury 350 MAG Manual page 127

5. Remove the seawater inlet hose from the seawater pump at the location shown. Plug the hose to prevent water from siphoning
into the engine or boat.
Seawater inlet hose connection—350/377 MAG ECT and SeaCore 350/377 MAG ECT
Seawater inlet hose connection—350/377 MAG and SeaCore 350/377 MAG
6. Using a suitable adapter, connect the flushing hose from the water source to the water inlet of the seawater pump.
Without sufficient cooling water, the engine, the water pump, and other components will overheat and suffer damage. Provide
a sufficient supply of water to the water inlets during operation.
7. With sterndrive in normal operating position, open the water source fully.
8. Place the remote control in neutral idle speed position and start engine.
Operating the engine out of the water at high speeds creates suction, which can collapse the water supply hose and overheat
the engine. Do not operate the engine above 1400 RPM out of the water and without sufficient cooling water supply.
9. Slowly advance throttle until engine reaches 1300 RPM (+/‑100 RPM).
10. Observe the water temperature gauge to ensure that the engine is operating in the normal range.
11. Operate engine with sterndrive in neutral for about 10 minutes or until discharge water is clear.
12. Slowly return throttle to idle speed position.
13. Stop engine.
14. Shut off the water and remove flushing attachments.
15. If the boat is out of the water, install the water inlet hose to the aft side of the seawater pump. Tighten the hose clamp securely.
16. If the boat is in the water, tag the ignition switch with an appropriate tag requiring the seawater inlet hose to be reconnected
prior to operating engine.
90-8M0050539 MAY 2011
eng
33208
NOTICE
NOTICE
Section 5 - Maintenance
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