Broken fuel Tap & what I learnt today

Discussion in '2-Stroke Engines' started by 1cc, May 9, 2007.

  1. 1cc

    1cc Guest

    Hit my fuel tap on the gate today & snapped it off.
    Found a few things that may be of interest to all, the inside of the tap only has a 1/8" hole for the fuel to pass through, this could be causing some problems with not enough fuel flowing to the carby when running flat out, causing a dead spot. I also found that the tank itself is not breathing, I managed to remove the broken tap & proceeded to let the fuel run out of the tank into a container only to find that the fuel stopped flowing. I had to remove the cap to get the tank to drain, so the tank isnt letting in enough air for the fuel to flow.
    While I acquire a new tap, it might be an idea for those of you having trouble with the engine not reaching full rev's that you try removing the fuel cap & let me know what happens. If the rev's increase we definately have a problem with the tank not breathing.

  2. JosephGarcia

    JosephGarcia Guest

    I noticed this today when I took my bike apart, as well.

    But the fuel lines themselves and the carb float bowl act as a resevoir for the fuel, and I never noticed a problem with enough fuel going through. I tested this today after I saw the problem in the tank.

    This is only about the 1/8 inch hole problem, not the tank getting enough air thing
  3. Guest

    Guest Guest

    I drilled a tiny hole in my cap before I ever finished the build. It hasn't spit gas out on me yet.
  4. SlicerDicer

    SlicerDicer Guest

    You know I have not used a lawn mower or weedwhip in years. Maybe 10 years? No need naturally I do not have grass. No matter but don't they all have a drilled hole for air?
  5. JosephGarcia

    JosephGarcia Guest

    The tanks on these engines are designed so the cap has vents that pull in air to replace gas in the tank. For the most part, they work fine. Maybe you got a bad cap. Replace it and run the engine for awhile to see if it cuts out or otherwise shows signs that its not getting fuel.
  6. 1cc

    1cc Guest

    Looks like Ill have to drill a hole in the cap as it is definately not venting, cheers
  7. Guest

    Guest Guest

    I ran a 1/32" bit through the top of the cap, it works great.