Dax Titan 50 engine problem... looking for help

Discussion in '4-Stroke Engines' started by bird_e, Aug 10, 2009.

  1. bird_e

    bird_e New Member

    Hello all,
    I have a Dax 50 titan engine on a friction mount. I bought this engine last year and have about 10 -15 hours on it.

    At first I had a leaking carb, the float and needle weren't sealing off. So I took the carb apart and cleaned it. I didn't notice anything strange. No dirt or goop at all. So i put it back together and the leaked stopped and things seemed good for a little while.. but now the engine starts sputtering at WOT. and seems to loose some power. It starts and idles great.
    I pulled the air cleaner off and ran it. Same thing keeps sputtering at WOT... it almost sounds like its popping or back firing a bit through the carb.
    Does anyone have any idea?

  2. unior

    unior Member

    I would start with the things you worked on. Is the carb sealed properly to the engine? Did you make any adjustments to the fuel settings? Whats the plug look like? I wouldn't hesitate to contact dax about it either.
  3. Esteban

    Esteban Active Member

  4. bird_e

    bird_e New Member

    Here are more details...

    The gas is brand new 87 octane.

    When I had a leaking carb, I took it part, cleaned it and put it back together. Only to find out, it was still leaking...
    I took it apart again and closely inspected the float and needle. I couldn't see anything wrong with it. If you are familar with this carb the need has a little spring on it where it attaches to the float. It gives a little pressure when then float is in the up position. I gave the spring a little stretch with the hopes it will create more pressure on the needle giving it a better seal. Which it did, no more leaks. The motor ran perfect for a few rides and now has developed this sputtering / missing at high speeds.

    Does anyone know if I can purchase just anew float & needle for this carb, in case that is what is causing it? But I don't see how this would cause it.
    I mean as long as there if fuel in the bowl, the carb just siphons it from the main jet.
  5. bird_e

    bird_e New Member

    It's seems fine today..

    Ok I took it out for a ride this afternoon. The engine seems fine and is running great the past 20 minutes. what gives?

    how critical is the ingition coil gap between the fly wheel and the coil?

    The only thing I did was remove the red cover to inspect the ingition wire and the kill switch wires where it enters the coil. put it back together and now it seems to run great. ?????:confused:
  6. unior

    unior Member

    I would venture to guess that you had some dirt in the carb still. A little piece obstructed fuel delievery at WOT. So it ran lean it enough it to break up.
  7. Esteban

    Esteban Active Member

    Still sounds like bad gas,,, even if it is fresh. I have bought bad gas many times in my life. Make up a new batch using a clean, new container, 89 octane, a fewdrops of Seafoam, & the correct amount of oil.
  8. 5-7HEAVEN

    5-7HEAVEN Guest

    Is your fuel pickup line in the deepest part of the tank?

    Is this line covered with fuel at WOT?

    I had EXACTLY the same problem with my front Mitsubishi engine on "The Dragon Lady". The morning commute was great, even WOT. Upon returning home there was less gas in the tank. As long as I was cruising the engine used less fuel and the pickup was submerged. At WOT the engines sucked as much gas as possible, exposing the fuel pickup and sucking air.

    With Mits engines the tank lies 90 degrees from its optimum position. The pickup is NOT where it should be, so it gets exposed to less/no fuel when the tank is low.

    Maybe that's your problem.:detective:
  9. MotorBicycleRacing

    MotorBicycleRacing Well-Known Member

    the Dax 50 titan engine has a top mounted gravity feed fuel tank

    the fuel tank sits on top of the engine
  10. bird_e

    bird_e New Member

    Thanks for all the replys... I think I fixed it. I tore the carb apart again.. This time I removed everything. Main jet, idle screw, butter fly, choke.... etc.. and I cleaned everything. Although everything looked fine. I also removed a little casting flash from the venturri. Put it all back together and it seems to be running fine now. I think there must have been **** somewhere. There is also a black plastic plug with a little jet in it it will some oring type seals. I believe this is the idle mixture jet. The origs were all boogered up, so I replaced them as well.
    I think it's good now!
  11. MotorBicycleRacing

    MotorBicycleRacing Well-Known Member

    do you have any photos of your Dax 50 titan engine on a friction mount

  12. bird_e

    bird_e New Member

    It wasn't fixed... The carb cleaning didn't resolve the issue. It still ran for **** and no power. So this is what I did. Since I had good spark, good fuel and a clean carb... I took off the valve cover to take a peak and inspect the valve adjustment, which should be about .05mm clearance...(I'm just be rough here).
    HOLY CR*****P.... I had almost 2mm of clearance in the exhaust valve and 1mm or more on the intake. The thing was waaaaay out of whack from the factory...
    Now the engine runs like a beast!!!!! I can't believe how powerful it is now. I'm a happy camper. I suggest if you feel like you are having performance issues with your 4stroke, check the valve clearance! It only takes a few minutes to do and WHAT a difference!

    That's why it was spitting and popping out the carb, the exhaust valve wasn't opening enough to let all the spent exhaust of the cylinder, so when the intake opened it went out that way!