Warm starting issues

Discussion in '2-Stroke Engines' started by shawnshank, Sep 15, 2010.

  1. shawnshank

    shawnshank Member

    My Tanaka 40cc engine was working flawlessly until I installed a bigger carb. It worked great initially, starting with just a few extra pulls then it did before I put the bigger carb on. I rode it a few times without issue (on separate occasions). Then on about the 4th ride, after having some difficulty getting it started I took it for a ride, got to the location and shut the engine off. I was off the bike for about 10 mins and went to start it and it took me over fifteen minutes and about 50 pulls to get it started. It wanted to turn over but would not stay running. I finally got it started.
    On my last ride, I rode a further distance, shut it off when I got where I was going, got back on after 5 mins and it took me even longer to get it restarted...over a half hour (I almost dropped kicked the thing into next week). I noticed some gas on the rubber gasget which attaches the air filter to the carb. I also noticed that when running, the bike idles high (the rear wheel will spin when I lift the bike off the ground. I'm not sure if these two things are related to the starting issue or not.
    Please help!

  2. Nuttsy

    Nuttsy Member

    I know your frustration with the not starting thing. I had a blower that did this and was never able to remedy the problem. In my case, motor was flooding. I would have to pull the spark plug and dry it and blow out the cyl., put it back together and it would start but I would immediately have to give it throttle or it sometimes would die again and then repeat the process.

    In your case, it sounds like an air leak and lean condition if the idle is racing as you say. Or you just need to lower the idle a bit. Did you pull the plug when it does this? Wet? Dry? Color?

    I found on my blower, if I needed to start it after shut down for a few minutes, it was best just to pull the starter cord--no throttle; no choke; just pull and pray. But be ready with the throttle if it does fire and blip it a little to keep it going. After a few seconds at high idle it was ok and ran great. The other alternative for me was to go do some other task for a half hour or so, then come back and start it right up! Go figger.
    Odd thing was, COLD it would start great at 2-3 pulls-choked.

    Maybe someone else can jump in here with a REAL solution.
    Good Luck!
  3. Whizzerd

    Whizzerd Member

    Just remember, kicking the thing across the street never mind next week could cause serious damage... to your FOOT! Have you tried reinstalling the original carb?
  4. unior

    unior Member

    Try starting it @ wide open throttle (if possible.) A flooded engine will start better at WOT no choke. You've got to be running too lean or too rich. But since it's only a hot start issue...and you installed a larger carb its prolly running too rich.

    You need a richer mixture when the engines cold so thats why she starts fine when cold.
  5. Reb

    Reb New Member

    I just installed the NT Speed carb and had some similar issues with my bike... it was idling really high and bogging down pretty bad at full throttle. The idle screw was making no difference in or out. I took the carb apart and moved the c-clip to the second notch down (it was on the first notch originally). I then adjusted the (much more responsive) idle to a very low setting. Now the bike runs pretty well- plenty of speed and acceleration off the line. I'm still having a little bit of trouble at full throttle; the motor sort of slows and then picks back up... I'm thinking that it's a spark problem. (any ideas?) Basically I'm saying you might want to move your c-clip around and see what happens... it might fix at least part of the problem.
  6. Nuttsy

    Nuttsy Member

    I can't speak for the OP, but in my case trying to restart with full throttle only made things worse for my blower. It would flood more and NEVER start until the plug was removed/dried and things cooled down for at least 1/2 hour. The cooling down thing was leading me to believe that it might be a heat soak problem and the carb was actually getting vapor locked. More common on small engines in hot climates in summer but in Boston???
    Small engines can be a PITA

    You must have missed the part about the Tanaka 40cc engine. Totally different animal from the C/G engines. E.g. no "clip" to move.

    Speaking of moving...looks like the OP
    DID! (move on) Hope he got it fixed. Be nice to let us know! Just sayin'.
  7. Reb

    Reb New Member

    yep, must have missed that part about the engine... oh well. should'a bought a grubee?
    ha ha.
  8. HeadSmess

    HeadSmess Well-Known Member

    replacement carb...a similar diaphgram carb? butterfly or slide type?

    my money is on an air leak...

    manifold.thingy. gasket. good, bad? do you have the little hole and slots lined up?

    (yes, look, youll see what i mean... theres more than just one hole in those gaskets)

    the hole is actually important, dang nammit! youll see its friend is on the carb itself... :)

    so check that.

    maybe its got a screw or two loose :p

    new carby or was it , ahem...donated? maybe a hole in one of its diaphgram membranes... this involves pulling it apart! hold em to the sky and if you see sky?

    theres something wrong :)

    in fact, in all my experiences... stripping the carby is about the first and most effective thing to do...

    im ASSUMING that cus its a tanaka its got a diaphgram carby...
    Last edited: Sep 23, 2010
  9. Nuttsy

    Nuttsy Member

    Well, it seems I've solved my hot starting problem with my blower. I found some Autolite brand spark plugs for small engines in K-mart for $1.49. I figured what the heck and bought some for my other small engines. I put one in the blower and Alah be PRAISED! That motor is now a one-pull-wonder now WHEN HOT!
    I'm not one to put much emphasis on which plug is better; which oil is better, etc. I've heard many complain about Champion plugs. All I know is that this plug solved MY problem. Shawnshank may give a different plug a shot. Couldn't hurt?!?! Or maybe try a different heat range???
    Just for info--my old plug was some Japanese NGK wannabe. It was in good condition--tan color, sharp edges, etc.
    Maybe there really IS a difference in plug quality?

    Hope this helps someone.