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  1. #1
    Chief Petty Officer
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    Default Mercury 3.3 HP gag/oil mix 2003

    Can someone advise the proper ratio of gas/oil for my 2003 Mercury 3.3 hp two stroke outboard motor?

    Thanks

  2. #2
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    Default Re: Mercury 3.3 HP gag/oil mix 2003

    Mix 50:1 with quality mfr's oil rated TCW-3 or better. Use regular unleaded non-gasohol if available, if all you can get is gasohol use regular, your little kicker won't need any more octane than that and higher grades have more alcohol which is less-than-desireable.

    Use a carbon-cleaning additive at least several times a season, this'll keep your rings from sticking. Seafoam is great stuff and also acts as a fuel system cleaner & fuel preservative. www.seafoamsales.com

    If you can't get Seafoam, all major outboard mfr's offer carbon cleaning additives and fuel conditioners. Chevron Techron additive works well, also.

    HTH & enjoy........ed

  3. #3
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    Default Re: Mercury 3.3 HP gas/oil mix 2003

    I thought these newer motors ran on something less than 50:1 , no ?

  4. #4
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    Default Re: Mercury 3.3 HP gag/oil mix 2003

    OMC flirted with 100:1 ratio's for a while, if that's what you mean by "something less than....". But I didn't think that Merc went radical on any of their little non-injected motors.

    The biggest problem with 100:1 was that it left too little of a residual oil film in the crankcase, to preserve bearings and other sensitive parts while the engine sat for a long time. So the parts would begin to rust. Not a good thing!

    Far as I know, all the non-injected Mercs ran 50:1 in 2003.

    Piqued my curiosity so I Googled and found this Wiki entry that indicates a 50:1 mix still:

    http://wiki.answers.com/Q/What_is_ga...rcury_outboard

    Can't confirm that source but it seems evident that 50:1 makes sense.

    I'm sure someone with an owner's manual can confirm.......ed

  5. #5
    Vice Admiral TOHATSU GURU's Avatar
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    Default Re: Mercury 3.3 HP gag/oil mix 2003

    The engine was actually designed by Tohatsu to run at 100:1 and will do so without any problem. The reason they were only released as 50:1 engines was due to the fear that people would not perform routine maintentanice on the cooling system and that the engines would not last long with reduced water flow through that coolant system.
    Elvin
    My answers are like Zen...It may not be the answer you want, but it is generally the answer you need.

    The 3 Rules:

    1) Look in your service manual first...Then ask me if it is correct.
    2) Understand that your desire to repair your engine does not mean that you have the ability to do so.
    3) If you are confused, take your engine into a dealer..Then let them be confused...At least, in theory, they sent someone to outboard 101.

  6. #6
    Petty Officer 1st Class sundowner205's Avatar
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    Default Re: Mercury 3.3 HP gag/oil mix 2003

    I have the Merc 2.5 hp - same motor just a smaller carb. I found out today that the motor is actually a Nissan/Tohatsu from TOHATSU GURU. Apparently all Merc's up to 30 hp are Tohatsu's.

    I needed a replacement carb and the Merc dealer wanted $165 for just the carb. Per GURU's knowledge, I called the local Nissan Marine/Tohatsu dealer and got the carb for $90.

    If you ever need parts for that motor - go through a Nissan/Tohatsu dealer - same parts but almost half the price.
    1989 Four Winns Sundowner 205 5.7 OMC Cobra

    Twin 2005 Seadoo RXT's

  7. #7

    Default Re: Mercury 3.3 HP gag/oil mix 2003

    is this ratio available for the 3.3 hp mercury two strokes from 1996 ?

  8. #8
    Vice Admiral TOHATSU GURU's Avatar
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    Default Re: Mercury 3.3 HP gag/oil mix 2003

    It's 50:1 regardless of year.
    Elvin
    My answers are like Zen...It may not be the answer you want, but it is generally the answer you need.

    The 3 Rules:

    1) Look in your service manual first...Then ask me if it is correct.
    2) Understand that your desire to repair your engine does not mean that you have the ability to do so.
    3) If you are confused, take your engine into a dealer..Then let them be confused...At least, in theory, they sent someone to outboard 101.

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