Draining; Replacing - Mercury 2.8 Diesel Operation & Maintenance Manual

The engine‑mounted water‑separating fuel filter is equipped with a water‑in‑fuel (WIF) sensor that should alert the operator
when water is present in the filter. This fuel filter needs to be replaced at specified intervals or whenever water is detected in
the fuel, whichever comes first.
The operator may be alerted that the WIF sensor has detected water in the fuel, depending upon the boat instrumentation
package and if equipped:
• A message may be displayed on an instrument
• An indicator lamp may be illuminated
See Instrumentation.
Drain or replace the remote mounted primary filter (such as a Racor® filter) at specified intervals, or whenever water is
detected in the engine‑mounted fuel filter.

Draining

The engine‑mounted water‑separating fuel filter can be drained of water and small dirt particles by opening the drain cap on the
bottom of the filter.
NOTE: To ensure complete draining in warm weather, drain the filter before starting daily operations. In cold weather, where
there is a possibility that the condensed water will freeze, drain the filter shortly after the end of daily operations.
NOTE: Place a suitable container under the fuel filter to catch contaminated fuel or water. Dispose of properly.
1. Place a container under the drain cap on the filter.
2. Open the drain by turning the drain cap counterclockwise (as viewed from the bottom of the filter) until fuel starts draining.
Do not remove the drain cap.
a
3. Drain until the fuel is clear in appearance.
4. Close the drain cap by turning clockwise. Tighten securely.
5. Fill the fuel filter. See Filling.

Replacing

Performing service or maintenance without first disconnecting the battery can cause product damage, personal injury, or
death due to fire, explosion, electrical shock, or unexpected engine starting. Always disconnect the battery cables from the
battery before maintaining, servicing, installing, or removing engine or drive components.
IMPORTANT: The element cannot be cleaned and reused. It must be replaced.
1. Disconnect both battery cables from the battery.
2. Disconnect the WIF sensor wires, if equipped.
90-8M0113987 DECEMBER 2015
eng
Typical water-separating fuel filter
a - WIF sensor wire connection
b - Filter
b
c - Drain cap
c
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WARNING
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Section 4 - Maintenance
Page 55