I finally got it running! (But not any more)

Discussion in '2-Stroke Engines' started by PabstBlueRibbonrulz!, May 31, 2009.

  1. The good news: I actually go the bike to turn on, stay on and EVEN stop.

    The bad news: A simple fuel filter change seems to have killed it.

    More specifically:

    I thought I had my K and N fuel filter installed incorrectly so I flipped in the other end up (the manufacturer just puts a vague arrow on it). After doing this the bike refuesd to start or even make starting noise. "I had it right the 1st time," I though and flipped the filter to its original position. Taking care to bleed out the air bubbles each time.

    Still wouldn't start. I later replaced the fuel filter all together and noticed it was quite dirty for only being ridden 5 mi or less. That made me think I gunked up the carburettor while doing the filter tango. I open the carburettor (inspected the bowl, and throttle housing) and it was spotless.

    So what on earth could it be. Does a bike that works fine one day just decide to give up on you?

    I hope the fuel filter is not just a "red herring." :detective: But it would be a heck of a coincidence if it was.

  2. Junster

    Junster Member

    Try taking the carb off and the carb bowl. Remove the slide and look thru the main jet in the center. Also check the fuel inlet to the carb and the float needle. It maybe plugged there. If there was alot of gunk it could have plugged the float needle and seat before it got into the bowl. I don't think bleeding out the bubbles is really needed. GL
  3. Pablo

    Pablo Motored Bikes Sponsor

    I think Junster nailed it. All the gok that you purposely flushed into your carb probably clogged the jet.

    I'm curious though. What is a "vague arrow"?
  4. Mountainman

    Mountainman Active Member

    fast ---------------------------------- cheap trick test to be sure ??

    so as to be sure it's a fuel problem
    remove plug -- table spoon of gas in there -- got any fire ??

    ride that THING
  5. I have a feeling you fellas are right. But for the most part the carb looks very clean. The brass fuel inlet still has its hole clean. What other crevices inside the carb are gunk-prone?

    The arrow simply point vertical. It's either up or down depending on how to look at it "this end toward enginge" or a simple "this end up" would have made it foolproof.

    **What part in the carb does the actual fuel/air regulation. Obviously that's what the whole contraption is for, but is there a specific piece/site where this happens?**
  6. Pablo

    Pablo Motored Bikes Sponsor

    The arrow is the direction the fuel flows.

    The main regulation happens at the main jet (center on stand off tube above float), which is a 0.70 mm hole in a brass fitting, but is also controlled with a needle that moves with the air flow barrel slide controlled by the throttle.
  7. This morning I blasted the carb with carb cleaner and then sprayed the cylinder with starter fluid. I actually started up and ran until it died (I may have over/under choked it). After dying I was able to start it twice more while the engine was nice and hot with out using started fluid.

    Just not I tried to start the cold engine. No luck. Sprayed it with stater fluid again no luck. If I had a serious fuel issue the engine would have died right after it consumed the starter fluid right?
  8. Pablo

    Pablo Motored Bikes Sponsor

    What does sparky look like? What plug are you using?
  9. At first the stock spark plug. I looks a bit sooty. But I tried NKG spark plug today and had the same problem.

    Something tells me the carb may be gunked up for good. If all else fails I might just buy a new carb.
  10. Pablo

    Pablo Motored Bikes Sponsor

    Have you taken the jet out? (pretty easy really)
  11. Junster

    Junster Member

  12. The jet is that brass tube that the fuel line connects to right? Or is it the tube the needle rests in?

    Tomorrow I will given every nook and cranny of the carb a good cleaning with compressed air and carb cleaner.
  13. Junster

    Junster Member

    No the fuel line nipple just puts gas in the bowl. On the bottom of it there is a needle that the float raises to stop the gas flow when the bowl is full. Check that. The jet is where you thought. At the bottom of the tube the slide needle goes down. Check it too with the slide out. The jet sits in the bowl of gas. Vacuum sucks gas up thru it to the intake at the rate metered by the size of the jet. Because of this the motors will run richer if the bowl is fuller cause it's easier to suck it up. So the fuel level kept by the float can make a noticable difference. (Adjusting the tabs on the float) hope this helps.
  14. Today I cleaned the carb so well it must have made Howard hughes envious. All for naught. It still didn't start. I'm going to go extreme and install a new carb AFTER lining the tank with kreem and replacing the fuel filter.

    If it doesn't work after that it can't be a fuel related problem.