Thread: Fouling plugs

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  1. #1
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    Post Fouling plugs

    <1B714735> I bought a 2009 Nitro with 200hp Mercury Optimax about a month and a half ago. It only had 53.1 hours! When I test drive it, it would get up about 50mph and give a 4 beep alarm. It was a dealership selling it for an individual and the dealership told me that it was just an oil sensor needed replaced. I got the boat at at good deal so I bought it. After checking this out online, it appeared that it might actually be the oil reservoir on the motor needing replaced. I bought a new oil reservoir, replaced it and never have gotten the alarm again......FIXED! But the mechanic at the marine shop (that I bought oil reservoir from) told me to “Swift shift” a time or 2 when I replaced it to ensure there was no air in the line (purge the line). So I did this a couple times immediately and then pulled it to a water hose to run it and allow the oil reservoir on the motor to completely fill to top as the crankcase pressure was supposed to automatically do this. Well it didn’t appear to be filling so I turned it off and before cranking it again, I did the “Swift shift” again. It seemed to be idling fine on the hose although it didn’t seem to be filling the reservoir. I figured it might need to be ran so I brought it to the lake, ended up doing the “Swift shift” again before cranking it, and before idling all the way out of the no wake zone it died and would not crank again. It turned over fine but acted the same way as if the kill-switch would’ve been disconnected. But it was connected. I brought it to a different marine shop (b/c the previous one was a couple hours away). They found that a rubber bushing had come loose and was blocking the high pressure fuel pump. I picked it up and went to the lake on the way home where it cranked and idled fine, took off fine, but then went to missing and bogged down. I couldn’t get it back up on pad so I idled in. At this point I called the marine shop and complained and they told me that it was probably fouled plugs and they didn’t have a lake nearby to put it under a load to test.......so I replaced the plugs. Brought it back to the lake and it ran great for 3-4 minutes before it started missing and bogged down again. I cleaned the plugs and same thing. I did this 2 more times before dropping it off at another (more reputable) marine shop. I told them everything. They’ve checked compression and said everything is good. They cleaned plugs and same thing happened to them when they brought it to the lake. They’ve supposedly emailed Mercury who told them to run some “quick-clean” through it. They called me and said it was ready and running fine. I asked them if they ran it at the lake and they said no,...but they would if I wanted them to before coming to get it. So the dud and ame thing- ran good for a minute or so before missing and bogging down to the point that it comes off of plane. It’s going on 3 weeks and they keep telling me that they think it’s a fuel issue but haven’t gotten it figured out. Is it possible that I dumped too much oil on the cylinders when I did the “Swift shift” 4-5 times when I replaced the oil reservoir on motor? Could this be what’s causing plugs to foul out and run horrible? If so, is there anything to do to correct the issue? Motor serial number is 1B714735. Please help!
    Last edited by EuropeanAM; 10-16-2019 at 04:04 PM.

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    #2
    You put the motor in "Break in" mode with the "swift shift". You were given BAD information to do a swift shift. You needed to have a " oil pump prime sequence " performed by a Dealer, after changing the reservoir.



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    #3
    Quote Originally Posted by Savage View Post
    You put the motor in "Break in" mode with the "swift shift". You were given BAD information to do a swift shift. You needed to have a " oil pump prime sequence " performed by a Dealer, after changing the reservoir.
    This.

    Also, have any of these shops checked pressures? Ran a full report? Done any actual troubleshooting other the dumping quick clean and changing the plugs?

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    #4
    You needed to bleed the reservoir tank by loosening the black cap and idle the motor until it starts to overflow

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    #5
    Savage, it was a mechanic from a marine shop who told me to do the “Swift shift”. I’m the one to blame for doing it too many times.

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    #6
    They checked compression. They’ve cleaned plugs. And they’ve put wuick clean through it. Im not able to get very much info from them when i call to get updates ( as it’s always the lady over the shop that I y’all to and not the mechanic who’s done any of the work. I know they’ve downloaded the computer info and sent to mercury and it was mercury who suggested putting the quick clean through it. But I doubt they’ve told mercury all of this info that I’ve included in the initial post.

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    #7
    Rdiesel01, I had the cap loose while the motor was running on hose but it didn’t ever seem to move (at all). I was expecting it to move within a couple minutes but it never did. I might have needed to wait longer.

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    #8
    Sounds like I need to quit calling them and show up in person to get a printout of everything they’ve done. They seem awfully slow on getting it fixed. It seems like it should be something simple.......but apparently not.

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    #9
    Quote Originally Posted by WarrenII View Post
    Savage, it was a mechanic from a marine shop who told me to do the “Swift shift”. I’m the one to blame for doing it too many times.
    You can't put it "break in" mode several times, every time after the first simply reset break in counter to 2hrs of double oil. Even in break in mode, the engine should still run, so IMO, there's something else wrong. Savage is correct, the proper procedure is to run an "oil pump prime" sequence which does not include break in oiling and a reputable mechanic should have known that.
    _______

    Phil
    '09 Hewescraft ProV
    '09 150 Optimax


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    #10
    Thanks for the info. I had no clue about “break in mode”. I may mention that to them, cause I’m not sure they know it. As you’re saying......they should! But I’m wondering if the lady over the shop has told the mechanics everything I’ve shared with her. I’ll let everyone (here) know what I find out after I y’all to them at the shop today. Again, thanks for such quick responses and the info y’all have shared!

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    #11
    I also noticed that every time I did the Swift shift that the oil in the small oil reservoir lowered. I’m assuming that I gorged the motor/cylinders full of oil. Could all of that extra oil still be my actual problem? And how long would it take to burn all that excessive oil off the cylinders? Also, if that is my actual problem, is there anyway to remove the excess oil from in the cylinders?

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    #12
    Run the boat for Two Hours at WOT, not continuously. The motor is going to continue to run double the amount of oil that it should, until the break-in clock expires. No way to stop the break-in cycle once it is started.



  13. Member
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    #13
    Quote Originally Posted by Savage View Post
    Run the boat for Two Hours at WOT, not continuously. The motor is going to continue to run double the amount of oil that it should, until the break-in clock expires. No way to stop the break-in cycle once it is started.
    ^^^^
    _______

    Phil
    '09 Hewescraft ProV
    '09 150 Optimax


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    #14
    Thanks for all the knowledgeable info! Got it from the shop today and it’s running great. I think we’ve finally ran it enough to get the excess oil burnt out along with the break in time over. Now just to get out in the water for some fall fishing! Thanks again!

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    #15
    WarrenII
    Is your motor oil reservoir now overfilling, like it should, when you leave the cap loose and run the motor? which I believe that was the original issue.

  16. Mercury 3L/4 Stroke/Verado Moderator EuropeanAM's Avatar
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    #16
    Just to clarify- you should not have EVER done the "jockey the shifter" technique. Incorrect method as it reset break-in AND performed an oil pump prime.

    You then reset breakin over and over (each time performing ANOTHER oil pump prime). I suspect by the time you were done you had dumped several cups of oil into the engine, which will, without a doubt, make for a real mess in terms of fouled spark plugs.

    Hopefully now that you have run it some, things have cleared up. Be careful where you get your information going forward.


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