No water coming out of generator

Discussion in 'General Maintenance/Repair Questions' started by Misterhelms, Aug 13, 2020.

  1. Misterhelms

    Misterhelms Member

    67
    Jul 5, 2020
    Oceanport, NJ
    2004 Sea Ray 340 DA
    8.1s Mercruiser
    Guys - can I ask a stupid question? I just bought a 04 340 DA. Generator was running fine and well maintained. Driving up the ICW in NC and the alarm goes off for the generator. I immediate shut it off and when we stop for the day try to turn it on to see if I can diagnose the issue. As stated here no water coming out of the exhaust. I don’t have an LED readout so there are no codes to determine issue but started it up to see if water would come out of the exhaust which it didn’t.

    My question is this - when I open up the sea strainer with the sea cock open would water rush into the boat if it was unclogged? I didn’t think about it until later but trying to figure out if it’s an impeller issue or blockage. With no water coming in I’m thinking it’s blockage. I don’t have a wet/dry vac but thinking of either using a coat hanger or turning on the hose and try to push out the blockage that way.
     
  2. Todd320

    Todd320 Well-Known Member

    Jul 21, 2016
    St. Petersburg, FL
    2007 Sea Ray 320DA
    Twin V-drive 5.7L 350 Horizon
    Yes, it would rush in pretty fast, but it doesn’t like shoot up. When mine was clogged, and I opened it, water just slowly filled the basket.
    Close the sea cock for the generator, open the strainer clean it out. Open the sea cock for a second or two, if water comes in quickly, great, there is no clog. If not, use something plastic to get the clog out, I used a sturdy zip tie, probably 1/4” wide, 8” long. There was a 90 degree fitting leading into the strainer, and that’s where it clogged up. Then, I opened the sea cock again, water flowed, so I closed it, closed up the strainer, then opened sea cock back up. You can check the impeller too, if it looks okay, crank the engine (and immediately shut it down) while looking at the impeller to make sure it is spinning. Replace the impeller, if needed, if there are pieces missing, they can get stuck in the heat exchanger, so that is another thing to be on the lookout for. Finally, if the engine did overheat (vs detecting the water flow issue, and shutting down) check the coolant level, and top off as needed. Sounds like yours detected the water issue and shutdown before overheating?
     
  3. Ididntdoit

    Ididntdoit Well-Known Member

    Dec 5, 2007
    New England & South Florida
    1976 17 Sport
    90hp Etec
    if it ran without water the impeller is bad
     
  4. Misterhelms

    Misterhelms Member

    67
    Jul 5, 2020
    Oceanport, NJ
    2004 Sea Ray 340 DA
    8.1s Mercruiser
    so I cleaned it out the other day and nothing in regards to water coming up happened. Based off that it sounds like I have a clog
     
  5. b_arrington

    b_arrington Well-Known Member GOLD Sponsor

    Feb 21, 2007
    Setauket, NY
    2018 Back Cove 34
    Cummins QSB 6.7 480
    Not necessarily. Many generators have a low water flow sensor that automatically shuts it down. This protect the engine and the impeller. I know from experience you can have multiple low flow shutdowns which the impeller being fine.
     
  6. Misterhelms

    Misterhelms Member

    67
    Jul 5, 2020
    Oceanport, NJ
    2004 Sea Ray 340 DA
    8.1s Mercruiser
    here is what I found 8427AAED-3E36-4E64-9F38-3A84852905D0.jpeg
     

    Attached Files:

  7. LMBoat

    LMBoat Member

    459
    Oct 4, 2006
    Ft Lauderdale
    1999 450 EB
    Cummins 6CTA's
    Kohler? While you have the impeller cover off, crank it and see if the impeller turns. If it does not, there a plastic coupling behind that plate that connects the water pump shaft to the crankshaft. They do fail. Part is not that expensive (get 2 one for a spare) and not that bad to replace. 2 bolts.
     
    Todd320 likes this.
  8. Misterhelms

    Misterhelms Member

    67
    Jul 5, 2020
    Oceanport, NJ
    2004 Sea Ray 340 DA
    8.1s Mercruiser
    Is the impeller supposed to be jammed in there? I don’t see how it could turn due to it being constricted in the housing. I see the plastic coupling - looks in tact. Do I need to put the screws back in before turning it on? Leave sea cock closed
     
  9. Stee6043

    Stee6043 Well-Known Member

    Jun 1, 2015
    West Michigan
    1997 Sundancer 400
    7.4L Gassers
    If water isn't coming through the strainer with the seacock open I'd suggest you pause on trouble shooting the impeller/pump.

    Can you get under the boat and check the inlet for debris?

    FWIW - your impeller looks fine to me. They do get "smooshed" like that, it's how they are designed. That said, it never hurts to replace that part when you're in there. They are <$30 and should be replaced every couple years.
     
  10. Misterhelms

    Misterhelms Member

    67
    Jul 5, 2020
    Oceanport, NJ
    2004 Sea Ray 340 DA
    8.1s Mercruiser
    Started the generator and didn’t see it turning. Took it off to see if the part that would spin it turns and it’s not moving either. At a loss
     
  11. brewster16

    brewster16 Active Member

    570
    Aug 9, 2009
    Long Beach Island, N.J.
    '07 44 Sundancer
    Twin Cummins QSC 8.3
    Certainly replace the impeller while you've got the cover off. But if I were you I'd certainly unclog the raw water inlet hose.....as it was stated earlier....with the raw water strainer cover off and the raw water inlet valve (seacock) opened water should be overflowing into your bilge. If it's not it's clogged.
     
  12. Misterhelms

    Misterhelms Member

    67
    Jul 5, 2020
    Oceanport, NJ
    2004 Sea Ray 340 DA
    8.1s Mercruiser
    Yeah - that’s definitely not happening
     
  13. SeadawgVB

    SeadawgVB Active Member

    317
    Jul 8, 2013
    Tidewater Virginia
    '03 Sundancer 360
    Twin 8.1s with V-drives
    I would focus on no water coming in with the seacock open and the strainer lid open. BUT if the impeller is not turning, look again at the inside of the coupler, should look like this:
    [​IMG]

    Sounds like you may have two issues. Maybe try back washing your cooling water line from the strainer to the thru-hull. Sometimes the little grate can get clogged. I've seen jellyfish so thick that they will jam in there so badly that only a diver can scrape it clean.
     
    sea hare likes this.
  14. Misterhelms

    Misterhelms Member

    67
    Jul 5, 2020
    Oceanport, NJ
    2004 Sea Ray 340 DA
    8.1s Mercruiser
    What’s the best way to back wash it? Currently traveling up the ICW. Supposed to rain later and would be great to have AC for the family so we can keep the windows closed.
     
  15. Stee6043

    Stee6043 Well-Known Member

    Jun 1, 2015
    West Michigan
    1997 Sundancer 400
    7.4L Gassers
    If you're underway I'd use a garden hose attached to the fresh water spigot in your transom locker.
     
    Misterhelms likes this.
  16. b_arrington

    b_arrington Well-Known Member GOLD Sponsor

    Feb 21, 2007
    Setauket, NY
    2018 Back Cove 34
    Cummins QSB 6.7 480
    Easiest way is to use a Sea Flush with a shop vac to blow it out. But I assume you don't have that right now. Next would be a flushing lid for your strainer, attached to a hose. I'll assume you don't have one of those aboard.

    Then I would try to get a fresh water hose into to hose that leads to the seacock and try to use water pressure to force out the obstruction. You might be able to remove the strainer basket and get the hose in there. Have a helper turn on the water for you.

    If you can't get a fresh water hose in the strainer, you might need to remove a hose from the strainer; this would be a last resort option for me because a) they can be very difficult to remove b) they can be difficult to reinstall, and 3) risks damage to the hose.
     
    Misterhelms likes this.
  17. SeadawgVB

    SeadawgVB Active Member

    317
    Jul 8, 2013
    Tidewater Virginia
    '03 Sundancer 360
    Twin 8.1s with V-drives
    The best way is by having an adapter that connects a garden right to the hose that leads toward your seacock / thru-hull.
    Since you probably don't have that, try connected your garden hose to the dock city water (that will have more pressure than your than you onboard spigot) and shoving it in you sea strainer and wrapping some rags around the hose to try and seal it and shoot water towards the thru-hull. (Being careful to not block the passage in the strainer that leads to the seacock.) If you are already away from the dock, you can try to use your onboard fresh water system.s wash down connection, but it will have less pressure.
     
    b_arrington likes this.
  18. b_arrington

    b_arrington Well-Known Member GOLD Sponsor

    Feb 21, 2007
    Setauket, NY
    2018 Back Cove 34
    Cummins QSB 6.7 480
    I couldn't really tell from the photo, but the impeller looked OK. Are there any chunks or whole vanes missing? If you have a spare impeller kit it wouldn't hurt to install it since the housing is open.

    Yes, some of the vanes are supposed to be compressed against the housing; this is how a raw water impeller works. The vanes press against the sides of housing as it rotates creating an area of high pressure and forcing the water into the engine. As they pass by the vanes straighten out creating an area of low pressure. This sucks in water from the raw water side.

    When installing a new impeller you always need to compress the vanes to fit it in the housing. This can be done with various degrees of difficulty. I had no problem installing my small generator impeller; my large main engine impeller was a royal #$&*#^. I plan on obtaining a tool to aid future replacement. Some non-petroleum lubricant helps also.
     
  19. liv2ryde100

    liv2ryde100 Active Member

    628
    May 17, 2012
    long island
    05' 340 dancer
    Twin 8.1's
    did he say he cranked it with the cover off impellor and it wasnt turning?
     
  20. SeadawgVB

    SeadawgVB Active Member

    317
    Jul 8, 2013
    Tidewater Virginia
    '03 Sundancer 360
    Twin 8.1s with V-drives
    I think I read that, which is why I copied that pic of the coupler. Sounds like he may have two issues going on at the same time.

    But I also noticed in his pic, that the allen bolts are still in place, and if I recall properly, the coupler is behind that plate. (Am I right about that??)
     

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