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  1. #1
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    Cutting out all of a sudden

    2007 250 optimax SN 1B473522

    The boat has been out from the winter storing with plugs, plug wires, VST filter, and a few other items that should not have anything to due with the motor changed during the winter. It have had it out a couple times on an idle only lake and then this week I ran the winter tank with cocktail and stabilizer out, approx 25 gal. I ran pretty much the entire tank dry but switched out before it ran completely out. After switching tanks I ran 15 min pretty hard above 5000 rpm and parked it. I returned today with the family for the long weekend and idling out I noticed a miss and when taking off the miss was confirmed with a loss of power although it did get up on plane it was certainly not running right. I have a couple thoughts but I am interested in any input as I would first prefer to prevent any damage and secondly I would like to get up and running for the weekend.

    Thanks for the help!

  2. Member
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    #2
    Check for spark at each cylinder as the problem is occurring.



  3. Member
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    #3
    This may be a silly question but what is the best way to check spark while running?

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    #4
    Inductive timing light, go wire by wire and watch the flash pattern or lack of one.
    _______

    Phil
    '09 Hewescraft ProV
    '09 150 Optimax


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    #5
    Are you still using your original fuel line? Do you have a remote tank you can try? Your fuel line might be collapsing.
    Chad Snow / Massachusetts
    2007 Ranger Reata 210 - Mercury Optimax 225 (#1B446134) - 12' Talons
    Carbon12’s @ Bow w/ AT- live 12 w/ 3D & live 7 @ Helm


  6. Member
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    #6
    Have the coils been updated mines a 07 and I'm having a similar problem and that what I think it is. Don or someone can run your serial number and tell you.

  7. Member
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    #7
    I’m am back from the trip and was unable to trouble shoot any further as I did not have the right tools. It acts like there is a miss one cylinder and it will come back and run normal from time to time. The way it is acting seems like an electrical/spark problem with one of the cylinders but just guessing at this point.

    The fuel lines were replaced several years back and it still has the original coil packs. This should show up when testing per the advice from Savage.

  8. Member
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    #8
    Ok I got the light on it tonight and both the port and starboard side bottom cylinders are not getting spark. Possible that both coil packs went out at the same time or is there something else that they both route through?

  9. Member
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    #9
    If both bottom coils went out at the same time after plugs and other service I would make sure the rubber access plug for removing the lower cowl wasn’t left out and drowning the bottom two coils.

  10. Member
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    #10
    Quote Originally Posted by Anthonysjo View Post
    Ok I got the light on it tonight and both the port and starboard side bottom cylinders are not getting spark. Possible that both coil packs went out at the same time or is there something else that they both route through?
    Swap suspect coils with the ones that are currently providing a spark.



  11. Member
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    #11
    The rubber access plug is good after inspecting this morning. The coil swap was performed and interestingly enough when swapping coils 5 and 6 with 3 and 4 I now have 3, 5 and 6 working and 4 is still not firing. I am assuming I have one coil that is completely done and another that may be flaking out?

    So do I swap just one or replace them all? The motor now has 280 hours on it...when I got it 4 years ago it had 65 so maybe I am due for some of this.

    I have noticed what I think is a slight drop in performance of the boat maybe 5-8 mph on the top end for a while now...I thought it was just me adding too much tackle. When it would barely get up on plane and then only run about 4,000 rpms and had a noticeable miss it was really easy to tell something was wrong. Is it possible that I have been missing a cylinder for a while now and not that I am down 2 it is finally noticeable or would this performance happen with just one cylinder being down?

    I appreciate everyone's help! I will be making another post next on my overheating alarms when idling.

  12. Member
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    #12
    I would be testing the wiring harness for the coils.



  13. Member
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    #13
    How would I go about testing the harness? It doesn’t explain why original coils from 3 and 4 work in the harness when I moved them down. Was thinking it had to be the coils when only one of the original 5 and 6 coils worked when moved to position 3 and 4 in the harness. Maybe my other post was confusing....

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    #14
    Any more comments on testing the harness? I am about to the point of ordering a coil as it appears at least one is dead.

  15. Member
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    #15
    Start with the obvious and see what happens.
    _______

    Phil
    '09 Hewescraft ProV
    '09 150 Optimax


  16. Member
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    #16
    Talked to Don and he got a set of coils over to me last week. I hope to get them installed soon and get some time on the water to test. What should be used on the harness connectors? Dielectric grease?

  17. Banned
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    #17
    Has the ECU been scanned for faults? Seems to me that is the obvious way to proceed here. Otherwise throw a bunch of parts at it and hope for the best. This problem is probably either a misfire or low voltage. Is the battery fresh? Fully charged? An AGM? (they suck on an Opti, BTW)

  18. Member
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    #18
    Quote Originally Posted by Captain Hazlewood View Post
    An AGM? (they suck on an Opti, BTW)
    They are THE recommended battery by Mercury. Maybe you meant a stator style EFI in which case they are NOT recommended
    _______

    Phil
    '09 Hewescraft ProV
    '09 150 Optimax


  19. Banned
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    #19
    Quote Originally Posted by SilverFox579 View Post
    They are THE recommended battery by Mercury. Maybe you meant a stator style EFI in which case they are NOT recommended
    Nope I said on an Opti... I switched to the AGM because of the recommendation from this site. My 300xs would not keep an agm charged. I run my boat 2 and 3 times a week. It was weird because the boat would start, but when you tried to run over 3 or 4k rpm it would cut out and put a low voltage fault in the ecu. I switched to a lead wet cell battery and have not seen a low voltage fault since. (several years) ymmv

  20. Mercury 3L/4 Stroke/Verado Moderator EuropeanAM's Avatar
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    #20
    Quote Originally Posted by Captain Hazlewood View Post
    Nope I said on an Opti... I switched to the AGM because of the recommendation from this site. My 300xs would not keep an agm charged. I run my boat 2 and 3 times a week. It was weird because the boat would start, but when you tried to run over 3 or 4k rpm it would cut out and put a low voltage fault in the ecu. I switched to a lead wet cell battery and have not seen a low voltage fault since. (several years) ymmv
    Strange- but likely 100% unrelated to this thread.

    Anthony... normally just inspect the connectors for any signs of deterioration and plug them in.

    IF you continue to experience problems, don't hesitate to try new PLUGS on those cylinders. Even a "new" plug is not necessarily a "good" plug (had one just today that ran fine when installed early in the week but was DOA today).


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