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  1. #1
    Petty Officer 1st Class Valv's Avatar
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    Default How to de-carb an Optimax

    I have a 1999 Optimax 150hp, how do you decarb a fuel injected motor ?
    1992 Silverton 34 Convertible w. dual station
    1990 Baha Cruiser 260 Fisherman

  2. #2
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    Default Re: How to de-carb an Optimax

    how about sea-foam in the gas Valv?

  3. #3
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    Default Re: How to de-carb an Optimax

    Good ?.We were told at the factory to NOT run anything but gas through the rail. I will see what I can find out at work.TMD

  4. #4
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    Default Re: How to de-carb an Optimax

    listen to the doctor Valv!!! understand somefuel injection systems can be damaged from it.

  5. #5
    Petty Officer 1st Class Valv's Avatar
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    Default Re: How to de-carb an Optimax

    Seafoam, will not decarbon motor, it will help with small varnish and gum deposits on injectors, and a little clean up on heads.I mean real decarbonizing, I have plenty of OMC spray, which does wonders, and would like to figure it out if there is a connector or something on motor where it can be sprayed bypassing fuel system. I know it might be not good to even run mix gas on High Pressure Fuel Injection motors, there were some debates foew months ago, seems viscosity will be changed and will damage motors.So if oil pump goes bad....better replace it, not run any mix.Thanks
    1992 Silverton 34 Convertible w. dual station
    1990 Baha Cruiser 260 Fisherman

  6. #6
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    Default Re: How to de-carb an Optimax

    I own a optimax 200, since the computer controls the oil mixture at different speeds, I doubt that carbon buildup would be a problem like in older 2 strokes. It calculates for the optimum performance, so most if not all the oil is burned. Just my opinion.

  7. #7
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    Default Re: How to de-carb an Optimax

    on car engines you can spray water vapor in the carb and that works really well.Zac

  8. #8
    Supreme Mariner roscoe's Avatar
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    Default Re: How to de-carb an Optimax

    Even a fuel injected engine has an air intake. Can't you spray the decarb through the intake?




  9. #9
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    Default Re: How to de-carb an Optimax

    By doing that you would saturate the Map sensor and ruin it...we were also warned of doing that at service school.IF you spray..you pay.TMD

  10. #10
    Supreme Mariner roscoe's Avatar
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    Default Re: How to de-carb an Optimax

    Hmmmmm???




  11. #11
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    Default Re: How to de-carb an Optimax

    I assume the Hmmm is directed at me?The Map sensor is mounted in the plenun. Any fluid that is sprayed in the intake will saturate the Map sensor... possibly damaging it and making it give false readings.This is right from the factory. Might have the wording wrong...but this is what I got out of it.TMD

  12. #12
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    Default Re: How to de-carb an Optimax

    What is wrong with removing the spark plugs and spraying SeaFoam or other product inside the cylinder, let it soak and then run the engine. I have read articles on the Fitch system and they say to spray in the air intakes, so with what is being said above, that would be a no no for the optimax.

  13. #13
    Supreme Mariner roscoe's Avatar
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    Default Re: How to de-carb an Optimax

    No the Hmmmm? was not directed at anyone. Just me thinking about the problem. I forgot about the sensors on EFI engines, as I don't have one right no, no even my van. OK, how about pulling the sensor out, doing the decarb, then re-install?Just a thought.Otherwise, I guess you just decarb from the sparkplug holes only.




  14. #14
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    Default Re: How to de-carb an Optimax

    Removeing the plugs and soaking the cylinders is the prescribed method.You will however find getting those bottom plugs out tedious and back in down right frustrating.Be patient and carefull as it is easy to cross up those plug threads in your frustration.Why the decarb in the first place?

  15. #15
    Petty Officer 1st Class Valv's Avatar
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    Default Re: How to de-carb an Optimax

    I think the solution to spray into plugs is best one. It will be a slow job, since I will probably have to leave cylinder to be cleaned in the TDC position, so it won't leak fluid into exhaust. One thing for sure, I will have to replace plugs, and these babies are $ 15.00 a piece....Thanks for the help everybody.
    1992 Silverton 34 Convertible w. dual station
    1990 Baha Cruiser 260 Fisherman

  16. #16
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    Default Re: How to de-carb an Optimax

    Hey Valv, If your Opti is running properly there should be no need to de-carbonize. An oil injected or pre-mix engines use oil in the fuel and, therefore in the combustion chamber. The oil in the fuel is the source of the majority of the carbon in the cylinders. Since the Opti (and FICHT) engines spray unmixed fuel on top of the piston, there is a HUGE reduction in carbon deposits and the effort and cost required to change the plugs is probably not needed. I would wait until the plugs need changing to "decarbonize" the cylinders. [just another opinion]Happy Boating!

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