Only runs with full choke

Discussion in 'Norm's 2 stroke repair center' started by mikaleno, Apr 25, 2017.

  1. mikaleno

    mikaleno New Member

    Joined:
    Apr 25, 2017
    Messages:
    10
    Likes Received:
    0
    I put in new rings a Hi compression head and expansion chamber. Now it only runs with almost full choke, if I take it off it dies. I'm running out of ideas..
     
    #1 mikaleno, Apr 25, 2017
    Last edited: Apr 25, 2017
  2. TheNecromancer13

    Joined:
    Jan 21, 2015
    Messages:
    603
    Likes Received:
    10
    Sounds like you might still have an air leak somewhere.
     
  3. mikaleno

    mikaleno New Member

    Joined:
    Apr 25, 2017
    Messages:
    10
    Likes Received:
    0
    Yes, the air leak is at the carb (NT) to manifold area. When I shoot starter fluid at the joint it raises the RPM. But how to fix it??? I have the O ring in there, I've tried foil tape on the joint, I've tried plumbers tape, I've tried RTV, nothing works.....
     
  4. TheNecromancer13

    Joined:
    Jan 21, 2015
    Messages:
    603
    Likes Received:
    10
    I used RTV on one once, but I had to use a ****load of it and it took 3 tries.
     
  5. Slogger

    Slogger Member

    Joined:
    Sep 8, 2014
    Messages:
    545
    Likes Received:
    3
    I've always used Permatex copper gasket sealant for any leaks. It never really dries, cleans up easy and lasts a long time. I've had the same tube for about 19 years.
    If it only runs on full choke it may have a whacked out float height or a clogged jet keeping it from getting the gas, too. I have had the jet clog twice and I have a filter in the line. The kit tanks are cruddy and the gasohol rots o rings and cheap seals sometimes. The tiny black cruds will clog stuff.
    Hope you get it going.
     
  6. mikaleno

    mikaleno New Member

    Joined:
    Apr 25, 2017
    Messages:
    10
    Likes Received:
    0
    Thanks' for the replies guy's. I've had the carb off and it's clean as a butter bean. I put a ton of RTV on it this time and I'll look up how to adjust the float.
     
  7. mikaleno

    mikaleno New Member

    Joined:
    Apr 25, 2017
    Messages:
    10
    Likes Received:
    0
    OK, I had a new (NT) carb lying around and threw that on, (no O-ring). That cured the full-on chock condition and it's now operating fine. Now I'm getting the 4 cycling condition and then it kicks in the does the 2-stroke, so it's on and off. I'm running 20:1 cos i'm breaking in my new rings. Do you think that's what making it do the 4-stroke?
     
  8. Slogger

    Slogger Member

    Joined:
    Sep 8, 2014
    Messages:
    545
    Likes Received:
    3
    Run it out or drain into a container and add a little gas to get to 32/1. Or mix a new batch. Too much oil actually makes your fuel/air mix leaner but all the oil washing through fouls up the running so you can't tell it.
    If it 4 strokes at low RPM but clears up and runs well at full throttle, your main jet is ok. Lean the needle by dropping it.
    If it 4 strokes everywhere it probably needs float height set, checked for tune and if still out (on the top end), rejetted, then set the needle.
    From idle to 3/4 throttle you're on the needle, from 3/4 on up the needle is withdrawn from the jet and the jet is all that counts.
    Hope this helps.
     
  9. mikaleno

    mikaleno New Member

    Joined:
    Apr 25, 2017
    Messages:
    10
    Likes Received:
    0
    Thanks' Slogger!! It bogs off of idle and then in the midrange all of a sudden it comes on and runs great (2-stroking) then at the WOT it seems to bog again. I will thin out my fuel as it has a fair amount of smoke coming out of my chamber.
     
  10. Slogger

    Slogger Member

    Joined:
    Sep 8, 2014
    Messages:
    545
    Likes Received:
    3
    Just guessing but after the gas is right drop the needle. It's all trial and error, but it is logical. Fun really. Take your time and change one thing at a time.
    To tune a new engine before its broken in is tough, just make sure it isn't overly lean but does 2 stroke most the time.
    Once the rings seat it might need more adjusting anyway.
     
  11. mikaleno

    mikaleno New Member

    Joined:
    Apr 25, 2017
    Messages:
    10
    Likes Received:
    0
    Yep, dumped what was left in my tank into my Ga. jug then topped it off at the station just to thin it out a little. Then dropped my needle one click to it's lowest setting. I'll test drive it tomorrow... I bet my neighbors love my new expansion chamber, it's crackling fresh. Lol.
     
  12. mikaleno

    mikaleno New Member

    Joined:
    Apr 25, 2017
    Messages:
    10
    Likes Received:
    0
    Okay I put my stock muffler back on again, I couldn't take the noise. When I took it off I noticed my brand new copper coated gasket had blown out at the bottom, go figure. It runs pretty good now except when I take off it bogs until it gets on the main jet.
     
  13. Slogger

    Slogger Member

    Joined:
    Sep 8, 2014
    Messages:
    545
    Likes Received:
    3
    If the engine hasn't finished breaking in, I'd leave it alone until it does. As they break in they become more efficient pumps. The jetting required will be changing.
    If it is broken in, needle at lowest setting, and bogging rich at the low end, check your float height. It could be too high feeding too much fuel.
    If that is good, try one size smaller main and start all over again.
    Ain't this fun?
     
  14. Tyler6357

    Tyler6357 Member

    Joined:
    Mar 15, 2012
    Messages:
    802
    Likes Received:
    10
    It sounds like it's 4 stroking pretty badly and that is what probably caused the blown gasket. If you have put the needle clip on the leanest setting and it's still 4 stroking you should jet down but Slogger is right, it is best to break the rings in before fine tuning.
     
  15. mikaleno

    mikaleno New Member

    Joined:
    Apr 25, 2017
    Messages:
    10
    Likes Received:
    0
    Thanks' Slogger & Tyler, yes I believe I'm getting a little ahead of myself and need to let the rings seat because it is running better little by little. Lol, yes this is fun as you fix things you learn.
     
  16. Slogger

    Slogger Member

    Joined:
    Sep 8, 2014
    Messages:
    545
    Likes Received:
    3
    Yep. I figured as you break in it will need that 'extra gas' that is making it burble. More power, more gas. An engine can be looked at like an air pump.
    The better those rings seal, the more air it will draw. Then the extra gas is just right. Best to break it in first.
    Good luck to ya, happy trails!
     
  17. mikaleno

    mikaleno New Member

    Joined:
    Apr 25, 2017
    Messages:
    10
    Likes Received:
    0
    Wow, I just did a compression test on this little air pump and it is producing 165 psi. Isn't that a little too much? I do have a high compression head. My plug is looking dark brown to blackish.
     
  18. Slogger

    Slogger Member

    Joined:
    Sep 8, 2014
    Messages:
    545
    Likes Received:
    3
    I don't know. you wanted high compression, sooo..
    ;)
     
  19. maniac57

    maniac57 Old, Fat, and still faster than you

    Joined:
    Oct 8, 2011
    Messages:
    4,486
    Likes Received:
    3
    180 psi is about the most you want without hammering rod bearings to death quickly.
    Sounds like you got a good one if you're at 165 and not done with break-in.....
     
  20. mikaleno

    mikaleno New Member

    Joined:
    Apr 25, 2017
    Messages:
    10
    Likes Received:
    0
    Cool, It's not too much then.

    Engine shuts down when I'm riding sometimes, I went ahead and ordered a new CDI and coil, the coil looks pretty cruddy. I had quite a few miles on it before I re-ringed it. Also ordered some jets 60-80.
     

Share This Page