• Rebuilding a Kohler Genset Water Pump

    You are performing your routine checks in the engine room and notice water dripping from the water pump on the genset. Upon further inspection you determine it is not coming from the hoses but instead from behind the pump. It is time for a water pump rebuild.


    This is a relatively easy project with the most difficulty presented by how easy it is to access your genset. If your boat is in the water close the seacock supplying the raw water to the genset. Now remove the pump by removing both hose clamps then the three bolts that fasten the water pump bracket to the genset.

    Attachment 593

    At this point the pump assembly should slide out of the bracket. Now remove the four screws holding the impeller cover in place.

    Attachment 594

    Remove the impeller cover and gasket.

    Attachment 595

    Take note of the orientation of the impeller vanes on the old impeller. This will allow you to install the new one correctly. Now using needle nose pliers remove the old impeller.

    Attachment 596

    Flip the pump housing over and on the backside, around the shaft is a lock-ring. Using lock-ring pliers remove the ring and the pump shaft should slide out the back.

    Attachment 598

    Once the shaft has been removed you can replace the shaft o-ring with a new one.

    Now using a flat punch, from the back of the pump knock out the inner shaft seal and replace with a new one.

    Attachment 599

    Lubricate the shaft and slide into the new seal. Now install the lock-ring and ensure it is seated fully. Install the new impeller 9lubricate with liquid soap) and ensure all of the blades tilt opposite the direction of rotation. In the picture below the vanes are NOT oriented properly and if you momentarily activate the genset starter they should seat properly.

    Attachment 600

    Once the blades are in the proper orientation, install the new cover gasket and install the cover.

    Open the seacock for the raw water, start the genset and check for leaks.
    franyfamilia and clcarter750 like this.


    Comments 1 Comment
    1. NBT22555's Avatar
      NBT22555 -
      where can i find the parts for this repair, nobody seems to sell the parts just the whole housing?
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