Mercruiser 470 Water Pump Parts

The Mercruiser 470 inboard engine was based on the 3.7-liter aluminum four-cylinder General Motors engine block and used the same water pump. The parts list for the water pump on Mercury Marine's Mercruiser 470 includes a list of the seals and gaskets, the parts that make up the front cover assembly, the impeller cover and the impeller for the pump.

  1. Seals

    • The pump's seals and gaskets ensure the pump leaks neither internally nor externally. The seals and gaskets in the Mercruiser 470 water pump include the two water pump seals, Part Number 67388, that fit on the shaft behind the impeller and the front seal, Part Number 97530, seated in front of the impeller and sealing the joint between the water inlet cover and the front cover assembly.

    Gaskets

    • The gaskets in the Mercruiser 470 water pump include the impeller cover gasket, Part Number 68714 A 6, surrounds the impeller, to seal the mating surface between the impeller cover and the front cover assembly. The front cover gasket, Part Number 68714 A 7, seals the mating surface between the engine block and the front cover.

    Front Cover Assembly

    • The water pump body comprises the three parts of the water pump that act as a channel to move the water through the engine -- the front cover assembly, Part Number 71903 A 2, the impeller cover, Part Number 71902 A 1, and the water inlet cover, 71904.

    Impeller Assembly

    • The impeller assembly, Part Number 12600 A 1, is the heart of the pump. The impeller turns to pressurize and move the water through the pump body and into the engine. The body of the pump is held together by 10 bolts, which not only secure the front cover and impeller cover together, but also secure the pump to the front of the engine block.

    Screws, Studs and Washers

    • Five front cover screws, Part Number 35386, secure the front cover assembly to the block. The impeller screw, Part Number 86462 A 1, along with the impeller screw lock washer, Part Number 23703 and the impeller stud, Part Number 12601, join the impeller to the front cover assembly. The cover screw, Part Number 67450 secures the impeller cover to the cylinder block and the impeller cover screw, Part Number 35386, secures the impeller cover to the front cover assembly. The inlet cover screw, Part Number 28668, and the impeller cover-screw lock washer, Part Number 21249, secure the impeller cover to the impeller assembly. The 10 washer cover screws, Part Number 20084, secure the front cover assembly and the completed pump to the engine block