"7g Ghost Racer not running: DESPERATE FOR HELP" *UPDATE*

Discussion in '4-Stroke Engines' started by Free_Rider, Sep 16, 2016.

  1. Free_Rider

    Free_Rider New Member

    Quick recap: Engine never turned on with the choke on but did with the choke off. Was able to start and run engine it until engine kept dying after coming to stops and attempting to give it gas. Engine stopped running altogether.

    After retracing the instillation process, I concluded that the wiring job for the kill switch was sketchy so my focus went here. I disconnected the kill switch and rewired the cables back to their original state.

    After doing this, the no start with the choke on remained but surprisingly the engine turned on with the choke off, just like before.

    Although this is leaps and bounds from a no start scenario, the idle screw had to be set to rev slighter higher than before to keep the engine running. Already this doesn't feel or seem right. And even though I was able to take her for a spin around the block, the engine feels weak and "off", like its hungry for either fuel or air. That, and the engine got quite hot for just a run around the block.

    It didn't turn off on me after coming to a stop so that's good.

    While progress was made, I don't feel confident that I'm in the clear. I sense a "calm before the storm" heading my way lol.

    This thread got me curious if the screw behind the brass plug on the carb is causing the no start with the choke on problem.

    These member has this to say:
    "On most hs142f engines there's a brass plug on the left side of the carb nearest the head. NOT the larger inset plug but the smaller one closest to the engine. Carefully drill out the plug with progressively larger drill bits starting with 1/8" or 3mm. Be careful to just drill thru the plug (its about 1/8" thick. After the plug is removed you will find an idle mixture screw. These are "factory set" and often are out of proper adjustment."

    "These are "factory set" and often are out of proper adjustment." You can say that again! My new motor started great when it was cold, but after warming up (10 minutes or so) it would die as I slowed to a stop. Taking the advice of the smart people in this forum, I removed the brass plug to gain access to the idle mixture screw. Lo and behold, the screw was set completely leaned out, fully clockwise! No wonder it wasn't getting any fuel! I used procedures found in another forum to adjust the idle mixture and found the motor ran great with the screw turned counter-clockwise 2 full turns (your result may vary). Thanks to all of you who share your knowledge and experience!"

    I'll keep tinkering away until I legitimately fix the problem. I'll keep you all posted.

  2. bakaneko

    bakaneko Active Member

    Oh, you don't have this available. Yes, remove the brass plug as soon as possible. I used a small bit and drilled a very small pilot nub into the plug and then used a sharp wood screw and screwed it in till it bottoms out and then pull the plug out.

    The mixture screw is very important to dialing in peak performance of your engine for your conditions. You would want to get a good power gradient over low to high rpms through dialing in the screw. It is clockwise for rich and counter clockwise for lean. This takes time to dial in just right but I would start with fixing your idle and a good performance over rpms and then really try to get the best setting.

    Also, I like to get my idle as low as possible. I think with this info you can probably tinker it more but I would try to get away from a high idle to keep the engine on.

    Here is more info from a different forum. It is good info. I am surprised that your engine needs this much tinkering since you bought it from someone who would have hopefully done all of this. I guess since the brass plug is still in he/she didn't bother with dialing in performance.

  3. Free_Rider

    Free_Rider New Member

    Hi Bakaneko. Wow, thanks for the enormous help. I bought the engine from gasbike.net, so based on their reputation, I don't think they adjusted anything on this engine. Never again.

    And you're right, I gotta get that idle as low as possible.

    Sounds like this mixture screw is critical when getting these engines to purr just right. Why would they cover it with a permanent brass plug? Anyway, we'll see what I uncover once I drill out this plug.

    Thanks again man.
  4. hazmat

    hazmat New Member

    i have only built 3 four strokes but i have noticed they all have carburetors that are extremely dirty buy some carburetor cleaner and flush out all the fuel paths after doing it 2 or 3 times ur engine should purr perfectly adjusting the idle wont help much till carb is clear and clean otherwise dirt particles in the fuel make idle adjustments almost impossible
  5. Jayroma

    Jayroma New Member

    Yes, a lot of people don't know about the hidden idle screw. If someone could put up a video of them reveling it, that would be awesome. I'm sure it would help out a lot of guys :)