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Delete the Generator Sea Water Pump Impeller?

Discussion in 'Generators' started by Thisisit, Jun 8, 2025 at 9:03 PM.

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  1. Thisisit, Jun 8, 2025 at 9:03 PM
    #1
    Thisisit

    Thisisit Member

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    I can't find the original thread about this issue, so I will re submit my question.

    Has anyone removed the impeller from their genny pump housing and replaced it with an electric pump setup?

    My Westerbeke 8.0 BTD is mounted in such a way that the seawater pump is on the back side.

    To change it out, I need to disconnect a whack of wiring and hoses, un-bolt the unit from the mounts and spin it at least 45 degrees. Then, I have to work left-handed (not that there's anything wrong with that) and with very little room and leverage.

    I understand that some have removed the Impeller, installed an AC pump and wired it into the AC output of the genny to provide the genny an uninterrupted supply of seawater.

    Has anyone had experience with this setup?
  2. Thisisit, Jun 8, 2025 at 9:16 PM
    #2
    Thisisit

    Thisisit Member

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  3. Capt Ralph, Jun 9, 2025 at 8:52 AM
    #3
    Capt Ralph

    Capt Ralph Senior Member

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    Well, It been six years already. How many impellers have been replaced since this first job?

    I do have another thought to ad not considered in the original thread; GPH..
    Not enough may not cool the engine and exhaust well.
    To much may cause exhaust restrictions or flood the engine with water.

    Try to find or calculate the gen-sets raw water flow, GPH or GPM and match a 230Vac pump to that.
  4. Pascal, Jun 9, 2025 at 9:25 AM
    #4
    Pascal

    Pascal Senior Member

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    That’s going to be tricky part: sizing the pump.

    march pumps are probably your best option if you go that route, they come in a variety of flow rating and are easy to service. Stay away from Cal pumps

    best advice for those reading this thread? Don’t buy a boat with lousy service access. A raw pump should be easy to access not buried behind the gen.
  5. Capt Ralph, Jun 9, 2025 at 11:17 AM
    #5
    Capt Ralph

    Capt Ralph Senior Member

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    Yep..
  6. jhall767, Jun 9, 2025 at 1:04 PM
    #6
    jhall767

    jhall767 Senior Member

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    I would wire it to a relay with a hobbs oil pressure switch. This will prevent it from running when the engine is not running. Otherwise you could flood the cylinders.
  7. MBevins, Jun 9, 2025 at 2:01 PM
    #7
    MBevins

    MBevins Senior Member

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    As well as the reverse, you should monitor the electric pumps outflow