MerCruiser 8.1 MAG, Owner'S Manual

Page: 125 / 152

Section 5 - Maintenance
90-864839070 AUGUST 2007 Page 117
NOTICE
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.
NOTICE
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.
SeaCore Power Package Flushing Procedure
NOTE: Flushing is needed only for salt, brackish, mineral laden or polluted water
applications. Flushing is recommended after each outing for best results.
IMPORTANT: Flushing the SeaCore power package with the boat and sterndrive in the
water is less effective. Flushing the SeaCore power package is most effective when
performed with the boat and sterndrive out of the water, such as on a boat lift or trailer.
MODELS USING THE STERNDRIVE WATER PICKUP
IMPORTANT: The system is designed to flush the Bravo sterndrive and the engine with
one water source. Do not block or remove the inlet water hose from the sterndrive to the
engine.
NOTE: Engines with the sterndrive water inlet blocked off at the gimbal housing: Refer to
Alternative Water Pickups.
!
WARNING
Rotating propellers can cause serious injury or death. Never operate the boat out of the
water with a propeller installed. Before installing or removing a propeller, place the drive
unit in neutral and engage the lanyard stop switch to prevent the engine from starting.
Place a block of wood between the propeller blade and the anti‑ventilation plate.
IMPORTANT: Do not allow the engine to pull air or seawater from alternative water pickup
sources during the flushing procedure. If equipped, ensure that all alternative water inlet
hoses are plugged at both ends.
1. Remove the boat from the water.