Gearbox problems

Discussion in 'Gun Building, Modifications & Repairs' started by schultzebomb, Oct 30, 2012.

  1. schultzebomb

    schultzebomb New Member

    1,528
    0
    Monterey
    I am building a dmr and im usuing an m150 spring. I shimmed the gearbox perfectly and everything. I am usuing an echo 1 high torque motor with an 11.1 lipo.
    Now here is the problem:
    The gun cycles about 3 times, but on the fouth time the gearboxlocks up and leaves the piston stuck back, when i pull the trigger the motor heats up and starts to smoke! It will not pull the spring anymore! How can i fix this! I know this motor can pull the spring but it just keeps refusing!
     
  2. EDI1st

    EDI1st New Member

    2,062
    3
    Fountain Valley
    Horrible motor, horrible wiring, bad shimming, bad battery etc etc.....

    How do you know the motor can pull it....?
    Most "high torque" motors that come in stock AEGs can't even pull M120 properly....
     

  3. TheAirsoftTech

    TheAirsoftTech New Member

    3,510
    4
    How do you know your motor can pull that spring?
     
  4. Archer627

    Archer627 New Member

    6,174
    5
    Figgington
    That motor is a ferrous motor IIRC. It's not going to be able to pull a heavy spring. Grab a Lonex Orange motor.
     
  5. schultzebomb

    schultzebomb New Member

    1,528
    0
    Monterey
    I know it can pull it bcuz i bought it seperatly its not a stock motor by the way, and the fact that it used to pull the spring just fine. And i hve brand new g&p wiring and a perfect shimm job.
     
  6. EDI1st

    EDI1st New Member

    2,062
    3
    Fountain Valley
    What motor is it....?
     
  7. schultzebomb

    schultzebomb New Member

    1,528
    0
    Monterey
    I think its a rebranded jg blue. Bcuz it is exatly the same as the jg one... I also used to use an amp high torque as well.
     
  8. EDI1st

    EDI1st New Member

    2,062
    3
    Fountain Valley
    Definitely the shimming.....
    If you do have perfect shimming.....like 9000% sure...then check the wiring...
     
  9. Lefse

    Lefse Well-Known Member Supporting Member

    4,744
    160
    What's the exact specs of the battery? Have you tried with a different battery?
     
  10. schultzebomb

    schultzebomb New Member

    1,528
    0
    Monterey
    11.1 25c 1800mah and a 9.6 3800 mah and i know they work and i know its not the shimming because the gears spin great with minimal play and plus i have reshimmed many guns, i know what im doing. And its not the wiring because its newish and it works when i put itin a different gearbox
     
    Last edited: Nov 1, 2012
  11. Col1500

    Col1500 New Member

    815
    0
    Kent
    What kind of gun are we even working with? And have you checked you cutoff lever and cleaned your trigger contacts?
     
  12. schultzebomb

    schultzebomb New Member

    1,528
    0
    Monterey
    Its a combat machine but it has absolutly no stock parts exept for the body. I put a new cut off lever in and new trigger contacts as well. I run power to the motor and let it spin freely, it runs normally but then i put it in the gearbox and it only cycles the gun about 3 times and then it locks up... Te motor can definatly handle the spring because it fires 3 shots at an actually decent rof, but on the fourth shot the piston just locks back all the way and the nothing, just when you pull the trigger the motor clicks. I will try taking the cut off lever out and having it just auto.. I think it may be the cut off lever.
     
    Last edited: Nov 2, 2012
  13. Ehudakineyah

    Ehudakineyah New Member

    2,510
    0
    Mililani
    Well, list all the parts that have been installed in this gearbox. And I'll try and help you.

    I'm gonna guess the shimming is good from your word. Make sure none of the bushings are cracked. Or if you're using all bearing bushings, check if they are not warped or bent in any way.

    You might want change out that motor. Drop in a high torque motor. Or change the ratio of your gear set. Chinese (stock) blue motors can pull a m150 on 30:1+ ratio on a 7.4v LiPo.

    What is the gauge of the G&P wiring? There are too many wire sets out there now. And the motor will only pull the amount of amperage it can, even with the big battery.

    Also check the piston you are using for any defects. Can be a fault in some cases. Even the cut off lever. Or even screwing the gearbox screws too tight.
     
  14. schultzebomb

    schultzebomb New Member

    1,528
    0
    Monterey
    I will probably just invest in a lonex motor. Which one shouldi get?
     
  15. Archer627

    Archer627 New Member

    6,174
    5
    Figgington
    Get a lonex orange motor (high Torque AKA A2).
     
  16. schultzebomb

    schultzebomb New Member

    1,528
    0
    Monterey
    Okay, that is the one i was looking at
     
  17. schultzebomb

    schultzebomb New Member

    1,528
    0
    Monterey
    The motor i was using might have been the problem! I think it is the brushes as they are very worn down and the wiring that comes off of them looks fried to a crisp!
     

    Attached Files:

  18. Archer627

    Archer627 New Member

    6,174
    5
    Figgington
    Those brushes :O. They need replacing :p. You may want to take apart the motor and clean it out to get the debris/residue from the brushes out.
     
  19. schultzebomb

    schultzebomb New Member

    1,528
    0
    Monterey
    I never realized how worn they were haha! I pulled them out an i was like wtf!?! When did that happen! But yeah i cleaned it out and ill clean it more, i already replaced em because i have a lot of spare ones laying around