Need check valve for my Bike Bug Spitz

Discussion in '2-Stroke Engines' started by mlcorson, Nov 2, 2008.

  1. mlcorson

    mlcorson Member

    I picked up an old Bike Bug, Spitz 2 cycle front wheel friction drive engine last week and need to replace the primer bulb and check valve. Its made by Tanaka and they don't make the parts anymore. I thought I could cobble together a bulb from a weedeater, mower etc. No joy there, did not work. After market primer bulbs usually come as one unit, an inlet and outlet. Not sure why, but the one I used didn't let the fuel flow after priming. Even reversed in/out. Basically, the primer bulb is on the tube (like a bulge) and the check valve, (between the bulb and the fuel pump) keeps the fuel from flowing back as you squeeze the tube. Any ideas for a source or how to construct a replacement?
    I really only need the check valve. It needs to fit on 1/8 fuel line tubing.
    Last edited: Nov 2, 2008

  2. Esteban

    Esteban Active Member

  3. Mountainman

    Mountainman Active Member

    if you can't find that small check valve -- try medical supply store ???

    the doctor said "I re-attached your torn part -- but please be careful when you

    ride that thing
  4. xPosTech

    xPosTech Member

    Didn't you ask this in another post? It was answered there.

    Last edited: Nov 3, 2008
  5. mlcorson

    mlcorson Member

    Sorry....somehow this double posted when I tried to change the title.
  6. xPosTech

    xPosTech Member

    No problem. At first I thought you had posted to another forum (I use "New Posts" searches) so had to edit. Some people post the same question in several forums when they can't wait for an answer. That's one way to get ignored.

    I'm just trying to help.

    Check valves are very simple devices. Just a weak spring pressing a ball against a seat. It takes only very slight pressure to overcome the weak spring. The springs are not as strong as the spring in a ball point pen.

    Since the springs are so weak to begin with, they don't usually wear out. A good cleaning with Carb or Brake cleaner will bring them back to life if the ball or seat is not damaged.

  7. mlcorson

    mlcorson Member

    Thanks, I just pulled an old valve off my old Mr. Coffee. Brilliant idea. I'll take it home and see if I can make it work. The tubing is probably useful on something also.
  8. xPosTech

    xPosTech Member

    Lets hope it works. If the spring and ball are the same or slightly smaller diameter it should work. There is the chance they might be too big to fit the chamber of the check valve. If it is too big maybe you could add it as an in line valve? The coffee machine type will work as a one way in line valve.

    I've seen some valves in carbs that work at a 90° angle - from flat surface to fuel line or vice versa. Sometimes these use a miniature leaf spring or a coil spring with just a couple of wraps. Another type of flat surface to line valve is a reed valve.

    Aren't some types of primer bulbs equipped with built-in check valves? These are probably reed type. Most of the primer bulb circuits I've run across suck gas from the carb and discharge to the tank, rather than pumping gas to the carb.

    Here's a pdf link to Walbro primer bulb theory. You'll need Adobe Reader, of course. You can either view it or download it.

    Good luck. I really hope it works.

    Last edited by a moderator: Dec 18, 2015