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Rebuilding Northern Lights raw water pump

Discussion in 'Generators' started by Pacmac, Sep 1, 2016.

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  1. Pacmac

    Pacmac New Member

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    Aug 8, 2016
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    Location:
    Vancouver b.c. Canada
    I have a new raw water pump for my 30kw northern lights genset. I also have new seals etc in my spare parts kit. I have changed out the pump with the new one and now I am trying to figure out how to change the seals etc. The old pump was leaking salt water at the shaft. Any advice will be welcome. Thanks
  2. Bamboo

    Bamboo Senior Member

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    Dec 19, 2008
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    Palm Beach, FL
    I haven't looked how to change the pump seals because a new pump is relatively cheap and they tend to last for many years. Let it be known as well that the stock impeller has 12 blades; there is a drop in 10 blade with beefier blades that pumps more water and is a better choice IMHO. Be sure to check the exhaust elbow where the raw water is mixed in if the part is five years since replacement or has 2500+ hours on it. This one is what they end up looking like- and they don't allow the water pump to pump water...

    IMG_1050.JPG IMG_1051.JPG IMG_1052.JPG
    Last edited: Sep 1, 2016
  3. Pacmac

    Pacmac New Member

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    Vancouver b.c. Canada
    The gensets have 7500 hours on them. We have replaced the elbows with s/s ones. The pumps I have been told are easily rebuilt I just have not figured it out yet. The seals come with the water pump kits.
  4. Capt J

    Capt J Senior Member

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    Just buy a new pump, they're cheap and not worth rebuilding. The reason the seals went is because the bearing is bad. If the bearing is bad, chances are the housing is eaten also.

    I haven't seen s/s elbows last any longer than the cast ones.
  5. K1W1

    K1W1 Senior Member

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    If you have a 30kW genset with 7500 hrs on it I would think that a new water pump is only the first component you will be rep;lacing sooner rather than later. I am actually quite surprised that a flexible impeller has lasted that long.
  6. Pascal

    Pascal Senior Member

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    I bet the impellers have been changed a few times... :) I ve had them last about 2000 hrs on NL 20. Depends on how much they are used as when impellers sits they take a set Also depends if they ve ever been run dry due to a raw water blockage.

    On the 20s the pumps a pretty cheap, not really worth rebuilding them if they have a few thousand hours. I carried a spare pump in addition Ito spare impellers
  7. Minnow

    Minnow New Member

    Joined:
    Feb 10, 2006
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    Location:
    Ft. Lauderdale
    the gear driven Jabsco pumps are fairly simple to rebuild and I do so regularly. Look at the schematic carefully and be sure you have all the parts before you start as it is much easier to do in one go.
    I think there is a circlip which does not have a part number from Northern Lights but you can get from Depco
    also you will need a puller to remove the gear and as mentioned above the shaft/housing must be in perfect shape. I too have purchased new and then put together the rebuild parts and have a in house reman floater pump