What tool to remove square hole Optimus SRV?

Discussion in 'Fettling Forum' started by Schensted, Sep 27, 2023.

  1. Schensted

    Schensted Subscriber

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    Hi,

    Got a quick question for our Optimus Gurus: I have an Optimus 111 coming in the mail that has the square (not penta or slotted) SRV on the fuel cap. Elsewhere on the forum I read that a Robertson screwdriver will work, but does anyone know the correct size? I’m anxious to have everything I need on hand so I can start fettling right away.

    Thanks!

    David in Virginia
     
    Schensted, Sep 27, 2023
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  2. night_owl

    night_owl Subscriber

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    Hi David

    The square opening on the SRV set screw on my Optimus Svea 123R measures 3.0mm. As the filler caps are interchangeable, I'd hazard a guess that it might be the same on your 111.

    I am not ot sure whether that corresponds to a particular Robertson screwdriver size(?). Maybe you can measure the screwdriver(s) you have. Otherwise, a metric 3mm square bit should work.

    Best,

    Christina
     
    night_owl, Sep 27, 2023
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  3. Schensted

    Schensted Subscriber

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    Christina, thanks for the info (and speedy reply). Robertson bits sizes seem to be non-metric (i.e. #1, #2, etc). I’ll pick up a 3mm square bit.
     
    Schensted, Sep 27, 2023
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  4. Schensted

    Schensted Subscriber

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    I just measured the tip of a #3 Robertson bit. It’s 3mm and tapered, so it should work fine. Thanks again @christina
     
    Schensted, Sep 27, 2023
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