Mercury 225 EFI, Service Manual

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MAINTENANCE
Page 1B-4 90-884294 OCTOBER 2001
Flushing Engine
Flushing Cooling System – Using Cowl Flush Plug
After each us in salt, polluted or muddy water, flush the internal water passages of the
outboard with fresh water. This will help prevent a buildup of deposits from clogging the
internal water passages.
NOTE: Engine can be stopped or running at idle speed when flushing the cooling system.
Do not flush engine using a water system that exceeds 45 psi.
1. Remove the plug from fitting in the bottom cowl.
2. Attach a water hose to the fitting. Turn water on and flush for 3 to 5 minutes.
Flushing Cooling System – Using Flushing Attachment 44357A2
WARNING
When flushing, verify that area in vicinity of propeller is clear and that no person
is standing nearby – to avoid possible injury. It is recommended to remove pro-
peller as a precautionary measure.
CAUTION
It is recommended that the front water pickups on the leading end of the torpedo
be blocked off (duct tape, etc.) while applying water to side mounted water pick-
ups during powerhead flushing or engine testing to prevent possible engine
overheat from air injestion.
1. Install Flushing Attachment 44357Q2 (or equivalent tool) on the gear housing from
the FRONT side, positioning the rubber cups over the water intake openings.
2. Connect hose [1/2 in. (12.7 mm) I.D. or larger] between flushing attachment and water
tap.
IMPORTANT: To prevent water pump damage, do not start or run engine unless
cooling water is flowing.
3. With the outboard in the normal operating position (vertical), partially open water tap
(IT IS NOT NECESSARY to use full water pressure) and adjust water flow so that
there is a significant water loss around the rubber cups.
4. Start engine and idle in NEUTRAL. Increase engine speed, not to exceed 2500 RPM.
5. Flush or service engine as required. Verify adequate cooling water is provided.
6. Water must be discharged thru “tell tale.”
IMPORTANT: Prevent engine overheating. If water flow is insufficient, stop engine
and determine cause before continuing.
7. Flush until discharge water is clear. In saltwater areas, run outboard 3 to 5 minutes.
8. Stop engine before turning off water.