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No 12 volt power

Discussion in 'Post Yacht' started by FencingAg, Feb 26, 2024.

  1. FencingAg

    FencingAg New Member

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    Oct 10, 2022
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    Location:
    Lake Charles, La
    So, I've been working on m7 1986 Post 43 for about 8 months, and after 2 months of not being able to get to the boat (it is 6 hours away from where I live), I come back and have no DC power whatsoever. Batteries are good (tested 3 times to be sure), but no power at the main panel. AC power works fine, and boat is on Shore power.

    Are there any breakers somewhere that I might be missing? Any ideas? Im going back this weekend and would LOVE IT if I could get this issue fixed.

    Thanks in advance for any help.
  2. Capt Ralph

    Capt Ralph Senior Member

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    Satsuma, FL
    If I remember, Battery switches can be overhead as you enter the ER from the cockpit. I have banged my head on these and moved the switch once.
    I do not remember a fuse but not stating there there in not one. Do you have a print set? Check for a ANL fuse somewhere.
    Also, the negative buss bars may be located outside the shaft/clutch couplings may have gotten wet/green. Check here for bad connections.
  3. Greg Page

    Greg Page Senior Member

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    Do you have power at the terminal for the DC main breaker on the back side of the panel? If that breaker goes bad you will loose DC on everything else.
  4. CharlesB

    CharlesB New Member

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    Eastern Shore, Virginia
    I have a 1988 46' Post. On the port side (hull side) of the port motor, there is a breaker down low that serves the house 12V panel. It is hard to get to, but it is there.
  5. FencingAg

    FencingAg New Member

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    No, I don't. That's a big part of my issue. And I don't know where to trace it from there.
  6. FencingAg

    FencingAg New Member

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    Can you be a little more specific as to where? Middle/front/rear of the engine on the port side? I actually have the port transmission removed right now, so I might be able to get to it more easily currently, especially since Im a big guy.
  7. Greg Page

    Greg Page Senior Member

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    If you need to trace the cable it is the one exiting top right in the photo. There is a junction block on the back face of the plywood where you can't see it. Should be easy to find where it exits the box in the engine room at forward bulkhead.

    Mine is non-standard from there but you hopefully can follow the cable once it's in the engine room.

    IMG_3535-small.jpg
  8. FencingAg

    FencingAg New Member

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    Location:
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    That does help, thank you. My wiring behind the panel is more of a rat's nest than that, and I will be going through all of it again this weekend. Thanks!
  9. CharlesB

    CharlesB New Member

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    Roughly middle of the block, down low. 6V92's in my post.
  10. CharlesB

    CharlesB New Member

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    Roughly middle of the block, down low. 6V92's in my post. Similar in location to the windlass breaker on the starboard motor.
    FencingAg likes this.
  11. Greg Page

    Greg Page Senior Member

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    This is the bottom side in the engine room. The heavy cable right in front is the DC (-). One of the black cables in the bottom left is the DC (+). The snake is the control cable to the genset that I need to pull out, shorten and re-pin. Installer did a good job on the rest of the wiring so I guess he didn't have tools or pins to re-pin that.

    IMG_3553-small.jpg