Can you fix my bike? No start, good spark, wet spark plug.

Discussion in '2-Stroke Engines' started by Leroybrown420, Nov 12, 2013.

  1. Leroybrown420

    Leroybrown420 Member

    Hello everyone. I'm new and going bald fast cuz I'm pulling my hair out over this crazy bike #13.

    The bike: Craigslist purchase Huffy Beach Addition - New HD wheels w/ 12g spokes, new tires & tubes, new chain, fresh grease in BB & Headset.

    The engine: New Grubee 66cc, New NT carb

    Mods: Mildly Ported intake, trimmed piston.

    The problem: The engine will not start. The engine did run after swapping all kinds of parts. Will not restart.

    Wiring: Blue to Blue - Black to Black, solder & heat-shrink connections - Magneto did not come w/ white wire.

    Fuel: 91 octane w/ royal purple synthetic 2 stroke oil. Mixed properly, taken from a working 66cc bike, less than 30 days old on the mix.

    Clutch: Working properly, cable is adjusted properly.

    The Story: Would not start after several tries. Tried over & over but would not start. Pulled plug, wet. Checked spark by turning the rear wheel counter clockwise. Lot's of blueish spark. Back together and back on the road still wont start. Starting with choke on (up), then part closed, finally turned off, no start. Pulled plug, wet. Install new plug, turned off fuel, let sit for 1-2 hours, tired again, nothing but wet plug. Still has spark. Tried new carb. New carb flooded engine so bad that fuel was pouring out of the muffler and off the rear engine mount. Installed 3rd new carb, still wet plug. Let sit overnight, fresh NGK plug and still can not get to run. Still has spark. Let sit, tied again. We plug and now has NO spark. removed kill switch, no spark. Installed new CDI and now has spark. roadtest and it runs. Let run for a few mins to clean out the excessive fuel. Called it a day.

    Next day, will not start. good spark. wet plug. let still, no start, wet plug again. For giggles pulled magneto, sanded the bottom. checked the position of the key slot on the crank. Key position is at 1 o:clock at TDC. Back together and still wont start. Has spark but now firing through the side of the stock plug boot. removed boot, cut wire back 1/4" reinstall new boot, good spark again. Engine still will not start and has wet plug. Removed carb. Made sure float was set to 21mm (gasket removed), moved the mixture setting up one notch leaner. Added Teflon to the drain plug, fuel inlet, jet, jet housing and added anaerobic sealant to bowl just because. Installed new 3 pron warmer plug, still has wont start and has good spark. WTF??? BTW, I did try a new piston and cylinder head out of desperation, nothing changed.

  2. Leroybrown420

    Leroybrown420 Member

  3. crassius

    crassius Well-Known Member

    I'd start swapping CDI units from bikes that run to this one - I've seen CDIs that had good spark, but were off time.
  4. HeadSmess

    HeadSmess Well-Known Member

    you pop the magnet off?

    make sure you its facing the right way, but 1 oclock sounds right. cant remember if that was where the key in shaft ends up at tdc or not, but...

    if it has spark, and the plugs getting wet...all it can be is spark timing.

    FLIP MAGNET OVER, just for giggles, and then contemplate a new cdi. the magnet obviously can be pushed on either way round. only one way is correct! it will produce spark either way. it has no marking either. helpful :)

    double, triple and skip four, go for a quintuple check that the key is actually in place AFTER installing magnet! superglue helps ;)

    yet it did firstly...dont put anything on the internal parts of the carb! go wash it out again.

    it flooded. thats a bad/sticky needle and seat.

    dont measure the fuel height in the bowl. just set it so the fuel is a few mm clear of bowl rim. ie, do it on the bench so its easy, and just hold the bowl in place with a finger when turning the fuel on and off... bend tabs rather than remove gaskets. as long as the jet is immersed, its deep enough ;)

    when it flooded...did you have to force it over? meaning a hydrolocked crankcase, with the only escape route being the very flimsy crank seal? check seals arent leaking or simply popped out altogether.

    though a wet plug would mean its getting past the crank and up into cylinder, so...meh!
  5. Leroybrown420

    Leroybrown420 Member

    Thanks for the help. Going to mess with it again this afternoon.

    I'm on my 2nd CDI as is, I do have a replacement CDI on order. The bike did start after replacing the CDI when I lost spark. I have good spark.

    Can not flip the Magneto upside down. The coil is offset so if I flip it around it will not lay flat on the block. It's kind of idiot proof. The blue wire is on top. The rotor has lots of magnetic power. The mounting surface is clean & flat. I might try a dab of dialectic grease on the mounting surface if I find a reason to take it back apart. more info on magneto, chick this link: Mystery.html
    since it did run once the timing and compression should be good.

    The engine did not hydrolock or seize in any way. It did start after the 2nd carb dumped fuel out the muffler.

    I'm crossing my fingers that it will just fire up today. I have all 3 ingredients needed for this b-otch to run (fuel, spark & compression). My plan of attack before I replace or change anything else is; Check spark, if good, install fresh plug. I did let her sit overnight with the plug out of the head and the fuel turned off. I did not drain the fuel from the bowl. Fuel off (the fuel shut off valve does work correctly, it's been checked), choke on (up), take her out and try to start. If it does not start after 5-10 min of riding around I'll come back. Check spark and see if the plug is wet. I'm not going to turn on the fuel at all, unless it starts. If the plug is dry I'll turn on the fuel & try, try, try again.

    There is a chance that I have already fixed this mug and have been chasing a flooded engine. I hope so. I'll keep you posted. I ordered a pull start. I'm getting sick of riding this bike. When it doesn't stat I want to knock it on the ground and jump up n down on it... Anyone have a match?

    Thanks again,
  6. Leroybrown420

    Leroybrown420 Member

    All fixed! Flipped the magnetic rotor over and put a dab of dielectric grease on the bottom side of the magneto. Fired Right up. Runs great!

    Thank you!

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    Last edited: Nov 14, 2013
  7. HeadSmess

    HeadSmess Well-Known Member

    see, i rock. flip the MAGNET over :) i am more than aware of how the magneto is made!

    mark it, so you know which way is which next time ;)

    dont go linking ME off to sites about the magneto. hmmph

    :jester: jk :jester:

    shame you cant paint the cylinder green too...

    but nothings stopping you from experimenting with anodising :)
    Leroybrown420 likes this.