Overheat warning horn fix

Discussion in 'Bubba's Outboards' started by BKS72, Oct 2, 2008.

  1. BKS72

    BKS72 New Member

    Messages:
    3,361
    State:
    East of KC
    The high-temp warning horn for my motor died. It's a 1980 Evinrude with the self-test horn (warning horn beeps when the key is turned on to let you know the horn is working). The horn is connected to acc. and key switch 12v sources and the ground is made when the switch in the head gets hot enough to "short" the switch to the block and ground the - side of the circuit.

    I wanted it fixed since that's the only warning I'd have if my motor was overheating but I didn't want to pay the $68 or so that BRP wants for a new one.

    So I bought an inexpensive (but very loud) backup beeper and wired it in in place of the old warning horn. I found an old momentary contact push button switch and wired it in paralell with the negative lead to the horn. This way I can push the button to activate and test the horn to verify it works. Saved me approximately $65.50 over buying the horn from BRP. Now all I have to do is make a sticker that says "Check Warning Horn" and stick it on the windshield where I'll see it every time I get in the boat:tounge_out:
     
  2. tbull

    tbull New Member

    Messages:
    3,318
    State:
    SW Ohio
    I recentley had to mess with my horn, one of the temp wires coming out of the #3 cylinder was so corroded that I could not even test the horn by grounding the lead from the harness. I had to snip down the connections and re strip the wires before it would even sound while I grounded it. Now mine does not give an alarm when I turn the key, unless the horn itself is sitting against aluminum, its a metal horn and took me a while to figure out why it would not shut off....duh:eek:oooh:....However, I do not get a horn at all when I put the key to the on position, I know alot of motors sound the horn while on the on position, then once started it goes off. Should I be getting a horn while on the on position, kind of like a test horn?
     

  3. BKS72

    BKS72 New Member

    Messages:
    3,361
    State:
    East of KC
    If it's a black, plastic, 3 wire horn, it should self test. P/N's for the warning horns on your motor that I could find were 584212 (side control box), 585149 (tiller), and 583931 (tiller).

    My self test horn has purple leads coming from the key switch and acc. harness (12v), tan wire coming from the harness that connects to the temp switch, and another black lead that (I think, I'd have to go look to make sure) goes to the key switch also.

    If yours sounds with the key on and the lead grounded out, you should be in good shape.
     
  4. tbull

    tbull New Member

    Messages:
    3,318
    State:
    SW Ohio
    Mine only has 2 wires, a purple and a tan I think, I know it only has 2 though and I get no horn when I turn the key.
     
  5. BKS72

    BKS72 New Member

    Messages:
    3,361
    State:
    East of KC
    If it sounded when you grounded it out, you should be fine. From everything I could find (and obviously take any of my info as suspect until Bubba gives you an answer) OMC made both - self test and non-self test horns. 3 wire are self test, 2 wire are not. If it activated as you said when you grounded the tan lead, you should be fine. Again, Bubba is the guy that knows stuff, I'm just going off of my experience in researching things for my motor:big_smile:

    I'm going to go tinker with my old horn and see if I can figure out how that self test circuit works - I'm suspecting that whatever the third, black lead is connected to is a momentary ground that activates the horn for a second as the key is turned, but I could be absolutely wrong, it may be something in the horn itself.
     
  6. tbull

    tbull New Member

    Messages:
    3,318
    State:
    SW Ohio
    Sounds good man thanks for the info
     
  7. BKS72

    BKS72 New Member

    Messages:
    3,361
    State:
    East of KC
    It's some kind of momentary contact in the horn itself that gives the short beep at startup. The black lead on mine goes straight to a constant ground. Probably explains why that horn is $68 or so:big_smile: