Exhaust Carb won't suck fuel, also exhaust pressure idea

Discussion in '2-Stroke Engines' started by combatcm@hotmail.com, Jun 14, 2009.

  1. My carb is having trouble getting fuel. If i open the fuel shutoff valve on the the fuel tank gas won't pour out. However if i take off the cap, fuel will pour out. I thought the caps were vented somehow, i can't really see however. I have the tank mounted on my rear rack which is above the carb. The gas dribbles and there are a lot of bubbles in the line. I push the primer and gas will slowly fill in the line. Then it'll start it up only to run about a mile then the line will run out of gas. Once the engine is off i have to manually fill the line by taking of the cap and priming it more.

    On RC cars, nitro engine have pressure lines that go from the muffler to the fuel tank to push fuel into the carb at a very low pressure. I was thinking of tapping nipples into the exhaust manifold before the muffler, and into the fuel tank to push the gas into the carb.

    Good idea?

  2. biken stins

    biken stins Member

    May just need to drill a small hole in it. vents get pluged.
    Had a slow fuel problem that turned out to be slag in petcock. eazy fix.
    As for pressure line don't seem like would do much good. No need to force fuel in for the most part i think, but could be wrong.
  3. fetor56

    fetor56 Guest

    Sounds right.
  4. Mountainman

    Mountainman Active Member

    not needed plus not a good idea

    no -- not a good idea

    don't want to blow your MB THING up !!!

  5. HoughMade

    HoughMade Guest

    A small hole in the tank will get you what you want w/o risk of explosion...and unless you are spending time inverted, you don't need a pressurized fuel system.
  6. Thanks for the advice. I drilled out what i think was the vent hole a little larger. It is the small hole above the o ring.