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Can I Put some 2-Stroke Gas/Oil Mix in my SUV tank?

I've got about a gallon of fuel that was mixed with 2 stroke oil for my '65 Vespa. I want to get rid of the gas, because it's been sitting in my garage since the fall. Would it hurt the engine at all for me to just pour it into my tank when I fill up? I figure 20 gallons of extra gas would really dilute the 2 stroke oil.
<br/> In case anyone is wondering, the premix is mixed at a 2% oil, 98% gas ratio.


  • edited March 2010
    Do you have a lawnmower or gas powered weedeater? I would use it in them before I put it in my 4-Runner. Gas like that also starts a good fire if you have a burn barrel. I would not risk my catalytic converter even if the risk is low.
  • edited March 2010
    No lawnmower or other 2-stroke engines in the house. I wouldn't want to hurt the cat, so maybe I'll just find a good way of disposing of it rather than taking any chances.
  • edited March 2010
    Our city has a once a month disposal program, they take old gas. If you have one in your fair city I would recommend that. Auto Parts and Repair shops may also take it as a courtesy.
  • edited March 2010
    If the gallon of fuel tank is not dirty, add it in 1/4 gallon portions to a near full tank of gas. I would not worry much.
  • edited March 2010
    I would pour it all in..Call it "top oil"..Won't hurt a thing..
  • edited March 2010
    If you have a 4 stroke lawn mower, you could use it in that. It wouldn't hurt a lawnmower engine even if it weren't diluted any further.

    I wouldn't use it in a vehicle made since 1975 though, not withstanding the fact that I don't care for SUV's and getting one more off the road wouldn't break my heart, I just can't do that to people.
  • edited March 2010

    Years ago, many of us used to add "top oil" to our gas tanks in order to provide upper cylinder lubrication.

    While I would not recommend this practice on a steady basis with modern vehicles (due to catalytic converters), adding a small amount over the space of perhaps three fill-ups of your tank should cause no harm.
  • edited March 2010
    I've been doing that for years. No problem so far.
  • edited March 2010
    No lawn mower at all. We live in the city, so I'm spared owning one.
  • edited March 2010
    2-stroke oil is supposed to burn ashlessly, so it should have no effect on the catalytic converter. I would pour it in without a second thought.

    If it were to damage anything, the first casualty would probably be the oxygen sensor(s) rather than the cat. Cats are designed to self-clean of contaminants.
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