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  1. #1
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    Opti Idle problems

    Hi all,

    Going through troubleshooting idle problems with my port 2000 Optimax 150 with ~650hrs. I did see that the previous owner replaced the rails in 2008. It has trouble idling and stalls often at idle but runs fine at higher throttle settings. I have replaced spark plugs and wires through normal maintenance. Just pulled the fuel rails for servicing and cleaning of injectors. I looked at the fuel and air regulator diaphragms and they are good. The tracker diaphragm, however, had a slight tear in it but i didn't see that it was all the way through but definitely torn if not on its way to opening up. I have a scan tool but it didn't enlighten me to anything that really stood out. Just looking for anybody in the same situation. BTW I run Techron Marine, Quickclean, and run only ethanol free gas. Search is also my friend so I did that before posting ;)

    Thanks!

  2. Mercury 3L/4 Stroke/Verado Moderator EuropeanAM's Avatar
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    #2
    Welcome to posting in the Mercury Forums! I've going to move your thread to the 2.5L forum for you.

    Please take a moment to look through the Announcements at the top of that forum and supply the required info (serial number).

    The TRACKER VALVE was your problem. Replace it and you will likely find the engine runs fine (assuming that the other diaphragms were not damaged in removal/reassembly- a very common problem).


    Dual Mercury Master Technician- for Mercury Outboards, Mercruiser and Mercury Racing at European Marine in Greenville, SC.
    Still consider myself a "Marine Apprentice" after 47 years (learn something new every day).
    Mercury Parts, Mercury Outboards, Smartcraft & Accessories, Injector Service, TDR Reeds- BBC Sponsor

  3. Member
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    #3
    Mine will do this if when I turn on the key do not wait for the self test to finish, the buzzer sounds wait until it goes off and then start.

  4. #4
    When mine was doing this a few years ago I finally traced it down to the reed valves. I first went through all the checks of injectors, spark plugs, tracker valve, etc. Replaced the reed valves with composites and it now idles like a champ. The only reason I went with composites were because of stories I hear of the metal reed valves failing/breaking and taking out an engine. If a composite does this it would be more likely just to get blown out with minimal damage.

    They must not have been closing completely.

  5. Member
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    #5
    just got my injectors back and one of the direct injectors was bad so maybe that with a questionable tracker valve. DO I need to replace the orings on the the injectors and the teflon seals on the DI's, they all look ok but dont know if this is the most recommended?

  6. Mercury 3L/4 Stroke/Verado Moderator EuropeanAM's Avatar
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    #6
    If you had the injectors serviced, they BETTER have new o-rings on them already. And I would hope that you were notified of the need to replace any bad seals.

    Those questions are best answered by whomever cleaned the injectors.


    Dual Mercury Master Technician- for Mercury Outboards, Mercruiser and Mercury Racing at European Marine in Greenville, SC.
    Still consider myself a "Marine Apprentice" after 47 years (learn something new every day).
    Mercury Parts, Mercury Outboards, Smartcraft & Accessories, Injector Service, TDR Reeds- BBC Sponsor

  7. Member
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    #7
    They did not say that they needed to be replaced, I did ask. I also inspected them and they look good. No cuts or cracks in the rubber o-rings and the teflon seals did not have any tell-tale blow by indication. I do not see where it is specifically called out to replace in the service manual or elsewhere. Only if they are worn.

  8. Mercury 3L/4 Stroke/Verado Moderator EuropeanAM's Avatar
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    #8
    Carbon dams are definitely an "as required" item. I do not recommend replacing them just "because you can".

    O-rings on the other hand really should be replaced when servicing the injectors or direct injectors.


    Dual Mercury Master Technician- for Mercury Outboards, Mercruiser and Mercury Racing at European Marine in Greenville, SC.
    Still consider myself a "Marine Apprentice" after 47 years (learn something new every day).
    Mercury Parts, Mercury Outboards, Smartcraft & Accessories, Injector Service, TDR Reeds- BBC Sponsor