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  1. #1

    Default 2 stroke oil choice

    Does anyone here burn 2 stroke synthetic in their outboards , are there any issues or beni's to burning it? I'd like to try it but never hear of guys talk about the stuff. Thanks.

  2. #2

    Default Re: 2 stroke oil choice

    There are a LOT of discussions on that subject. I run synthetic in mine mainly because it is becoming so common but i do see less smoke.

  3. #3
    Join Date
    May 2007
    Location
    Inverary, Ontario, Canada - The Great White North Eh!
    Posts
    9,114

    Default Re: 2 stroke oil choice

    If it's a carburated motor I can't think of "what extra value" the cost difference would give you.

    You are still mixing at 50:1 (or if your motor has a variable oiler, at whatever rate it mixes at) - so not giving you "extra mileage".

    Traditional 2 strokes are already inefficient (as opposed to new direct injected models) - so you have lot's of unburnt oil/gas going out the exhaust - if it's synthetic that just means you are paying two or three times more for what you aren't using (along with what you are using).

    Two strokes get damaged by a lack of oil. That is almost never the "oils fault" - if you have a clogged carb in a multi-carb set-up so that no mixed fuel is getting to say #2 cylinder, it doesn't matter "what oil" didn't get there.

    Now if you are running an injected motor there has been much discussion about, minimally, a semi-synthetic being easier on the injectors and if you have a direct-injected 2 stroke, most mfg's insist that you must run fully synthetic, but the regular old carb'd 2 strokes were designed to run on regular old dino-oil and there is hundreds out there that are 30 or 40 years old which kinda tells me that you don't need anything fancier for their longevity.

    I don't know if synthetic is anymore (eco-friendly) and if you lean that way then maybe it's a reason to use it, but the newest of my 4, well used outboards is a 1991 model and none of them have ever had any issue using dino-oil or 10% ethanol fuel (ran them on E-15 for two years when one of our stations was test selling the stuff - so ran it "just to see").

    So "for me", if the mfg say dino-oil is fine, I tend to believe them and unless a product that costs two or three times more lasts two or three times longer, or makes it run better/stronger/faster (at which point I have to judge if the improvement warrants the extra cost), I just stick with what works...
    Graham

    A "professional" is someone who gets paid for their work - it doesn't necessarily mean they are good at it :)

  4. #4
    Join Date
    Nov 2011
    Location
    tennessee
    Posts
    2,616

    Default Re: 2 stroke oil choice

    Now if you are running an injected motor there has been much discussion about, minimally, a semi-synthetic being easier on the injectors and if you have a direct-injected 2 stroke, most mfg's insist that you must run fully synthetic,
    Need to clear his up....DI motors do not send oil thru the injectors as its crankcase injected and mixed with incoming air. The only motors that send oil thru injectors are the EFI's as its mixed in the VST tank. Your 250 EFI will benefit from using synthetic as it has less ash/carbon...
    Pappys Sales and Service
    Owner and Factory Certified Technician
    Former racer KDBA (Kentucky Drag Boat Association)

  5. #5

    Default Re: 2 stroke oil choice

    Thanks for the input here guys i have a 250 EFI MERC that i have been running the dino stuff since forever, seems i do a lot of plug changing. I saw the chemical structure difference of the 2 oils and the synthetic looked a lot better on ALL oils so i switched over in my car's BUT was holding the stuff in my hand at the store and just couldn't do it for the 2 stroke with-out knowing, sounds like it's time or past time to change. Question is, can i add the synthetic to the dino if i run it down in the tank or what is the transition here? thanks.

  6. #6
    Join Date
    Nov 2011
    Location
    tennessee
    Posts
    2,616

    Default Re: 2 stroke oil choice

    Remember there are two type of synthetic....full and semi
    Pappys Sales and Service
    Owner and Factory Certified Technician
    Former racer KDBA (Kentucky Drag Boat Association)

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