Click for Westport Click for JetForums Click for Burger Click for YF Listing Service Click for Delta

Tank Level Indicator

Discussion in 'Technical Discussion' started by 3 Ray, Dec 17, 2011.

You need to be registered and signed in to view this content.
  1. 3 Ray, Dec 17, 2011
    #1
    3 Ray

    3 Ray New Member

    Joined:
    Feb 28, 2008
    Messages:
    11
    Location:
    Lansing Michigan Area
    I have a 1986 Sea Ray 41 ft Aft Cabin and the black water tank level indicator lights: 3/4, Full and Do Not Flush do not work. There are three wires leading into the cap of the holding tank. Has anyone ever removed this cap or replaced the probes? I really don't want to remove this cap if its isn't necessary. Maybe this tank monitor is too old to get replacement parts for and I should look into a new tank monitoring system? Any ideas?
  2. Capt Ralph, Dec 17, 2011
    #2
    Capt Ralph

    Capt Ralph Senior Member

    Joined:
    Sep 8, 2004
    Messages:
    13,439
    Location:
    Satsuma, FL
    Yep, stinky job. If it is the sender I'm familiar with, you will find 3 floats, usually stuck in place with stuff. Clean it best you can and test before installing it back. Hopefully there is a plug (usually not on a SR) to help avoid twisting the wires as you unscrew the sender from the tank.
    Lay a old wet towel over the tank to help odors from escaping.

    Again make sure to test before installing it back. Have also found bad LEDs in the panel display.
  3. 3 Ray, Dec 18, 2011
    #3
    3 Ray

    3 Ray New Member

    Joined:
    Feb 28, 2008
    Messages:
    11
    Location:
    Lansing Michigan Area
    Sounds like a good plan rcrapps. I'll check LEDs first. Wet towel is great advice, thanks. You wouldn't happen to know the company that makes the floats in case they need to be replaced? Correct, there is no plug but 3 wires can be easily removed from the cap they are attached like wires to a ignition coil.
  4. Marmot, Dec 18, 2011
    #4
    Marmot

    Marmot Senior Member

    Joined:
    May 20, 2007
    Messages:
    3,311
    Location:
    9114 S. Central Ave
    It sounds like an old Sealand TankWatch system. If this is the unit, Google tankwatch and you should be able to find more information.

    Attached Files:

  5. sunchaserv, Dec 18, 2011
    #5
    sunchaserv

    sunchaserv Member

    Joined:
    Dec 16, 2011
    Messages:
    140
    Location:
    Carefree, AZ
    On my Sealand tankwatch (per the picture Marmot posted) each probe has a hand nut that can be loosened allowing the probe to be lifted and shook around to get them working again. No smell or fluid loss occurs during this maneuver. The lowest or green probe is normally the problem. Every tank dump I add/flush water so the green light light comes on indicating a thoroughly cleaned/dumped tank.
  6. Fishtigua, Dec 18, 2011
    #6
    Fishtigua

    Fishtigua Senior Member

    Joined:
    Jul 20, 2007
    Messages:
    2,935
    Location:
    Guernsey/Antigua
  7. 3 Ray, Dec 20, 2011
    #7
    3 Ray

    3 Ray New Member

    Joined:
    Feb 28, 2008
    Messages:
    11
    Location:
    Lansing Michigan Area
    Thanks to all who replied. I removed the cap, cleaned and vacuumed tank, really wasn't too bad. The cap has three threaded brass probes all are worn off and the 3rd was actually a SS screw that I don't believe is original. The connections at top of the cap are labeled FULL, 3/4 and COM. The Black wire was connected to the COM which I think may mean COMMON. The white wire was connected to the 3/4 connector and the green wire was connected to the FULL connector. My panel LEDs are labeled 3/4, Full and Do Not Flush.
    My theory is that the COM probe is hot and the brass rod should extend about 1/4 of the way down into the tank. The probe labeled 3/4 should extend down into the tank the same distance as the COM probe. When the tank gets 3/4 full a current will travel between these two probes lighting the 3/4 LEDs. The probe for the Full indicator should travel down into the tank to a point an inch or two below the inlet to the tank from the heads. When the tank fills to this level both the FULL and Do Not Flush LEDs should light. To test this, which I won't be able to do until after the holidays, all I should have to do touch together the blue and white wires and see if the 3/4 LED lights. Then touch thew blue and green wire to see if the FULL and Do Not Flush LEDs light up.
    To repair all I should have to do is replace the threaded brass rods. Don't know why one is SS. (Previous Owner may have done this and the indicators haven't worked since?)
    Any comments or anyone with experience with this system let me know what you think of my theory.
    Thanks!

    Attached Files:

  8. Marmot, Dec 20, 2011
    #8
    Marmot

    Marmot Senior Member

    Joined:
    May 20, 2007
    Messages:
    3,311
    Location:
    9114 S. Central Ave
    Wow, that is a bronze age unit. Play with it, brass rod and a die are cheap.
  9. Capt Ralph, Dec 20, 2011
    #9
    Capt Ralph

    Capt Ralph Senior Member

    Joined:
    Sep 8, 2004
    Messages:
    13,439
    Location:
    Satsuma, FL
    Are the probes wired directly to the LEDs ? OR, is there an IC (chip) or two hiding on the board behind the LEDs?
    I would not think SS lead is original.
  10. Capt Ralph, Dec 20, 2011
    #10
    Capt Ralph

    Capt Ralph Senior Member

    Joined:
    Sep 8, 2004
    Messages:
    13,439
    Location:
    Satsuma, FL
    I can only go back as far as 1989 SR aft Cabin with the IPBs (illustrated part breakdowns). But even there, the sender is just listed as a "185033 cap and probe". No mfg info is stated and no details.
    Do you see any Mfg markings?
  11. Capt J, Dec 21, 2011
    #11
    Capt J

    Capt J Senior Member

    Joined:
    Jul 11, 2005
    Messages:
    14,530
    Location:
    Fort Lauderdale
    Why don't you just order a new Tankwatch sender instead of playing with E.coli covered parts on your desk?
  12. Capt Ralph, Dec 21, 2011
    #12
    Capt Ralph

    Capt Ralph Senior Member

    Joined:
    Sep 8, 2004
    Messages:
    13,439
    Location:
    Satsuma, FL
    poking in my thoughts

    While we constantly work on our Ole Bert, repairing and replacing tis, tat & other tings, I find personal reward in repairing what I find when I can. Figuring out how it's supposed to work, making it work again, improving it sometimes (more power ra ra ra) could be some of the therapy that boating is about.
    And;
    Have you seen the co$t of theses sending units???
  13. Marmot, Dec 21, 2011
    #13
    Marmot

    Marmot Senior Member

    Joined:
    May 20, 2007
    Messages:
    3,311
    Location:
    9114 S. Central Ave
    Maybe because some times it is not just about how much crap is in the tank.
  14. Capt Ralph, Dec 21, 2011
    #14
    Capt Ralph

    Capt Ralph Senior Member

    Joined:
    Sep 8, 2004
    Messages:
    13,439
    Location:
    Satsuma, FL
    Whats in a name

    I don't find any extra thrill working on MSDs, but I should be good at it by now with a ****** last name like mine;
    Ralph Crapps :)
  15. 3 Ray, Dec 21, 2011
    #15
    3 Ray

    3 Ray New Member

    Joined:
    Feb 28, 2008
    Messages:
    11
    Location:
    Lansing Michigan Area
    Okay, this is fun! If I can get this "Bronze Age Unit" to work for a few bucks I'll be pretty pleased with myself. Note, all parts were soaked in a bleach solution. I have no idea how this beast is wired. The leads behind the LED's are all zip tied to connectors that go someplace? I'll let you all know how it progresses after New Years. Thanks to all and have a great peaceful holiday season.
  16. Marmot, Dec 21, 2011
    #16
    Marmot

    Marmot Senior Member

    Joined:
    May 20, 2007
    Messages:
    3,311
    Location:
    9114 S. Central Ave
    I thnk you will find the longest probe is a "common" that should be connected to the negative. Take a set of Radio Shack alligator clip test leads and a 1K ohm resistor and clip one end to a terminal and the other end to the resistor and touch the other resistor lead to the other terminals and you will soon figure out which is which. Polarity matters as far as the common probe is concerned since you don't want an energized rod sitting in electrolyte just dissolving itself for no good reason.