Self FixerCom.DE

Water Pump disassembly2002-2004 Mercury Bigfoot outboards

NOTE: If the water tube coupler stayed on the water tube (inside of the driveshaft housing) when the gear housing was removed, pull the coupler from the water tube.

1. Replace the water tube coupler, if damaged.
2. Remove the six bolts and washers.
3. Remove the water pump cover.
   IMPORTANT:
   The circular groove formed by the impeller sealing bead should be disregarded when inspecting the cover and plate as the depth of the groove will not affect water pump output.
4. Replace the cover if the thickness of the steel at the discharge slots is 1.50 mm (0.060 in.) or less, or if the grooves, other than the impeller sealing bead groove, in the cover roof are more than 0.75 mm (0.030 in.) deep.
5. Lift the impeller, drive key, plastic washers, and gasket from the driveshaft.
6. Inspect the impeller. Replace the impeller if any of the following conditions exist:
   
   • Impeller blades are cracked, torn, or worn.
   • Impeller is glazed or melted (caused by operation without sufficient water supply).
   • Rubber portion of the impeller is not bonded to the impeller hub.
7. Remove the face plate and gasket.
8. Replace the face plate if the grooves, other than the impeller sealing bead groove, in the face plate are more than 0.75 mm (0.030 in.) deep.
9. Remove the water pump base by lifting gently, as shown. Inspect carefully for cracks.
10. Remove and discard the seals if damaged. Secure the base to a bench top or lightly clamp the base in a vise when removing the seals.
    IMPORTANT:
    Do not scratch the water pump base when removing the seals.
11. Replace the seal and filler plate if damaged or worn.



Updated on: Wednesday, November 11, 2020