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  1. 03-11-2025, 06:05 PM #1
    tnbassin
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    2017 Mercury 4 Stroke Ignition Problem

    I just got off the lake. I had a problem with my ignition switch. It turns all the way around without starting the engine. I kept trying until I finally got it to start and get back to the ramp. I guess it fell in to the right spot. When I tried it again on the trailer, it just spinned. I am obviously not a boat mechanic, but I assume I need a new ignition switch. Do you agree? How do I figure out which one to order online? I have 2017 Ranger Z518 with a 4 stroke Mercury 150. Thanks for the help.
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  2. alli ss
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    #2 03-11-2025, 11:35 PM
    Tighten it

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  3. Jbass123
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    #3 03-12-2025, 05:55 AM
    Quote Originally Posted by alli ss View Post
    Tighten it
    Yep. There should be a threaded ring on the back of the key switch, behind the dash. Tighten that while holding the key switch on the front, in the desired position. Note: I had this happen on a Ranger with Evinrude, but I’m guessing it works the same with a Mercury on the same boat.
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  4. EuropeanAM
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    #4 03-12-2025, 02:11 PM
    IF the entire switch ASSEMBLY is rotating around, then yes: Loosen the outside nut, turn the inside nut closer to the dash (1-2 turns) and then reinstall the outside nut SNUG.

    Now if the tumbler is just turning around and around inside the switch- that's a totally different problem.


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  5. tnbassin
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    #5 03-13-2025, 11:25 AM
    It was a loose plastic nut. I got it just snug and it worked. Only problem I found was that if I tried to tighten the plastic nut real tight, the nut would break loose and spin. I tightened it again just enough that it didn't break loose and also put some threadlocker on it. Hopefully that stuff works on plastic too.
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  6. EuropeanAM
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    #6 03-13-2025, 11:40 AM
    I would plan to order a replacement switch assembly from a Tracker Dealer, just so you are prepared and don't have to deal with it on the water.


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  7. desertbirdaz
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    #7 03-13-2025, 12:18 PM
    Quote Originally Posted by tnbassin View Post
    It was a loose plastic nut. I got it just snug and it worked. Only problem I found was that if I tried to tighten the plastic nut real tight, the nut would break loose and spin. I tightened it again just enough that it didn't break loose and also put some threadlocker on it. Hopefully that stuff works on plastic too.
    Blue loctite can eat some plastics and degrade them.
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  8. tnbassin
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    #8 03-13-2025, 03:43 PM
    Quote Originally Posted by desertbirdaz View Post
    Blue loctite can eat some plastics and degrade them.
    Of course. Thanks for letting me know.
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  9. mactlman
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    #9 03-13-2025, 07:47 PM
    Quote Originally Posted by tnbassin View Post
    Of course. Thanks for letting me know.
    super glue maybe
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