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Vac Valve to airbox line is broken. Criticality of this?

Discussion in 'Kawasaki 250cc In-line 4's' started by DamnitLaverty, Aug 26, 2016.

  1. DamnitLaverty

    DamnitLaverty Doing things the hard way since '78!

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    So the vac valve has a line that looks like it's supposed to have an elbow that hooks into the airbox. It seems to be broken and drawing air from outside the airbox. I'm a little unclear on what this valve does- do I need to fabricate an elbow to get it into the airbox, or is it OK drawing atmosphere? Obviously, doing it right mandates fixing this, but until I get crazy with the epoxy, is there anything wrong other than losing filtration on the vac valve by having it open and not going into the airbox?
     
    DamnitLaverty, Aug 26, 2016
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  2. Adam Giles

    Adam Giles Well-Known Member

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    The vacuum valve is for emissions reduction. I would strip it out all together. Plumb the bike back up as the a-model is.

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    Adam Giles, Aug 26, 2016
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  3. DamnitLaverty

    DamnitLaverty Doing things the hard way since '78!

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    Once it's running right, i'm on it! Thanks! One problem at a time tho. :)
     
    DamnitLaverty, Aug 26, 2016
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  4. Adam Giles

    Adam Giles Well-Known Member

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    New set of vacuum pipes might just help the running issues...

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    Adam Giles, Aug 26, 2016
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  5. Adam Giles

    Adam Giles Well-Known Member

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    I'm in UK an emission aren't check on a bike this old. Might be different where you are.

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    Adam Giles, Aug 26, 2016
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  6. DamnitLaverty

    DamnitLaverty Doing things the hard way since '78!

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    The vacuum lines leading up to the carbs are all soft, pliable and don't leak. Verified those first off. I haven't checked the lines on the valve. I'll give 'em a look. If they are crap, and I delete them, do I have to go to the pilot settings for an A model? I seem to keep reading they're a little different between the bikes.

    I'm in Seattle- in this state bikes are emissions exempt. Plus this bike is old enough to be import-legal now, which makes it so the EPA doesn't care federally, and so on and so forth. We don't have MOT/inspection here anyhow so i'm golden.
     
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    DamnitLaverty, Aug 26, 2016
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  7. Adam Giles

    Adam Giles Well-Known Member

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    Keep pilot settings as normal to start with. Vacuum from inlet 1+4 should run to petcock. Vacuum from inlets 2+3 should just be joined together.

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    Adam Giles, Aug 26, 2016
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  8. Adam Giles

    Adam Giles Well-Known Member

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    Breather pipes from top of carbs run to airbox.

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    Adam Giles, Aug 26, 2016
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  9. DamnitLaverty

    DamnitLaverty Doing things the hard way since '78!

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    AAAAH! So the 2/3 tee runs to the vac valve? I tested the line while installed but couldn't trace where the other end went with the carbs in place!
     
    DamnitLaverty, Aug 26, 2016
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  10. Adam Giles

    Adam Giles Well-Known Member

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    On C model, yep.

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    Adam Giles, Aug 26, 2016
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