DR350 Carb hose -HELP

Discussion in 'Thumpers' started by maxjett, Jul 25, 2012.

  1. maxjett

    maxjett Ride with Rocko Supporter

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    where does the hose go that connects to the top of the carb. mine is mising the hose ( vacuum line). This is a 1998 DR350
    #1
  2. Stretch67

    Stretch67 Mad Scientist Supporter

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    The vacuum line from the carb to the back of the fuel petcock?
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  3. AustinJake

    AustinJake DR650 - Versys

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    Don't vacuum sources usually come off the intake manifold?
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  4. Beezer

    Beezer Long timer

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    'bout as big around as a pencil? left side I think... thats a vent/drain line & the hose just goes overboard by the rear wheel
    #4
  5. maxjett

    maxjett Ride with Rocko Supporter

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    I was talking of the diaphram cover that has a connector which I now believe should be plugged off. I did find a loose vacuum line (hose) pencil size that appears to be pushed up into the frame backbone under the tank.
    I do have an off idle stumble on the bike. I will be removing the carb for a clean when I get time and want to first see if its hose vent problem.
    #5
  6. AustinJake

    AustinJake DR650 - Versys

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    There is ONE vent hose on every carb that is the bowl vent. It cannot be sealed off or the bike won't run. It has to have access to air, preferably dry air, but not a vacuum.
    #6
  7. maxjett

    maxjett Ride with Rocko Supporter

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    DR350 Dual sport owners can you take a look and maybe tell if the diaphram cover on top of the carb had a cap on it! If there is a line running up under the frame not down to the rear of the engine.

    I have a loose line that is running up into the backbone of the frame and the loose end is just by the carb which I dont see a place for it to connect on the carb.
    #7
  8. groundrules

    groundrules Long timer

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    Oh hiya
    there are two hose nipples on the right side of the carb. one is a vent that connects to the hose that should be routed up through the frame. This vent is often subject to the "T-vent Mod" as seen here:
    http://advrider.com/forums/showthread.php?p=15787664&highlight=vent#post15787664

    There is another hose nipple farther forward from the vent line that goes to the OEM vacuum <s>carburetor</s> PETCOCK, as seen here:
    [​IMG]

    I do not think that there is a cap on the diaphragm cover. there is not one shown on the parts fiche, and as you can see in the photo above, mine doesn't have one either.

    [​IMG]
    #8
  9. Stretch67

    Stretch67 Mad Scientist Supporter

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    None exist on the intake manifold of DR250/350's.
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  10. DistantHorizon

    DistantHorizon n00b

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    Yes, that is for the vacuum hose going to the petcock
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  11. Stretch67

    Stretch67 Mad Scientist Supporter

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    Perhaps the same black plastic diaphragm cover is used on other carbs / bikes where it is used as a vent, vacuum signal port, etc. But on DR250/350's, it's nothing but a port-shaped protrusion, blocked solid on the inside.
    #11