MerCruiser 3.0 MPI Owner's Manual page 101

3. Ensure the clogged blue drain hose is in the correct position below its connection point
on the block.
4. Turn on the bilge pump and supply water to the water inlets. If the boat is out of the
water, install the flushing attachment and open the water source fully to provide
maximum water flow.
Flushing Device
5. Start the engine and allow it to operate at idle until the obstruction is cleared from the
hose or for approximately 1 minute, whichever occurs first.
6. Check for water draining from the blue drain hose. If after 1 minute of idling, the blue
drain hose is still clogged, proceed to Step 7. If water is draining, shut off the engine
and continue with Step 3 of Single Point Drain System.
7. Shut off the engine. Disconnect the water source if connected to a flush device.
8. Attach the female end of the water hose adapter fitting to a water supply.
9. Attach the clogged blue drain hose to the male end of the water hose adapter fitting.
10. Fully open the water supply and allow it to run for 1 minute.
90-899883272 MARCH 2008
a
a - Flushing attachment
9192
Hose Adapter Fitting (22‑863840)
7358
91‑44357Q 2
Attaches to the water intakes; provides a fresh water
connection when flushing the cooling system or operating the
engine.
7252
Section 6 - Storage
Page 93