Gearbox issues

Discussion in 'Gun Building, Modifications & Repairs' started by airsoftdude101, Aug 8, 2015.

  1. airsoftdude101

    airsoftdude101 New Member

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    A gearbox I have been working on recently has been doing some weird things. First off I shoot it in semi only shoots once then locks up and I can't fire then I switch to full auto and it works perfectly, then when I switch it back to semi it happens again thanks for the help in advance.
     
  2. gregomacomb

    gregomacomb New Member

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    Chesterfield
    You probably already thought of this but did you try a new cut off lever.
     

  3. DreadCo526

    DreadCo526 New Member

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    Sylvester
    There is nothing you can really do to just fix this. You would have to completely change the timing in your gearbox. Put a bigger spring or a active breaking mosfet thats about the only 2 ways to solve this.
     
  4. TheInfidel23

    TheInfidel23 Resident Derp Supporting Member

    9,926
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    Greenville

    This makes zero sense. Whatsoever.

    Semi locking problems have to so with the cutoff and trigger contact relationship. It's fixable.

    I bigger spring or AB MOSFET would do nothing for this problem.
     
  5. AirsoftRyan778

    AirsoftRyan778 Active Member

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    54
    Baltimore
    Try getting a high torque motor if you dont have one already, and check your cutoff for wear
     
  6. DreadCo526

    DreadCo526 New Member

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    Sylvester
    The gearbox locks up on semi for one main reason. the sector gear cam is resting on the cut off lever, pushing it up in the way of the trigger trolley. Changing the timing with a stronger spring will force the sector to stop after the cycle is completed, preventing it from resting on the cut off lever. the active breaking mosfet will also force the gear to stop after cycle completion, this mod would be more expensive tho.
     
  7. NeoAugAU-3G

    NeoAugAU-3G Active Member

    2,918
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    Las Vegas
    Your 18 post experience is showing. There are many POSSIBLE reasons for semi only locking up. The main culprit (roughly 90% of the time) it is a simple worn cut off lever. These things wear out over time and need to be changed. Please refrain from speaking in the future, everyone will be better off.
     
  8. airsoftdude101

    airsoftdude101 New Member

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    Well actually all the parts are new in this gearbox
     
  9. Dannyboyextreme

    Dannyboyextreme Active Member

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    Burbank
    if all you did was drop in, that usually causes issues. Hell, my friends ak would only shoot full auto if I didnt check everything worked as it should and modded to make it work.
     
  10. Topper

    Topper Resident Donkey Supporting Member

    2,396
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    New Orleans
    Neo, that has got to be the most polite way I've ever seen someone tell another to shut up I've ever seen.
     
  11. airsoftdude101

    airsoftdude101 New Member

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    Seems like no one really saw that all the parts are new lol
     
  12. NeoAugAU-3G

    NeoAugAU-3G Active Member

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    Las Vegas
    This is info that would have helped in the FIRST post. A complete build list (every part) might help us determine where the issue is, include what kind of battery you are using, any mods you have done, the works.
     
  13. airsoftdude101

    airsoftdude101 New Member

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    Very true sorry about that I guess I didn't deem it relevant. The parts inside are all stock echo 1 except there is a ics wire harness, src selector plate, shs 16:1 gears, and a ares cylinder. And I am using a 11.1 15c Lipo battery.
     
    Last edited: Aug 12, 2015
  14. NeoAugAU-3G

    NeoAugAU-3G Active Member

    2,918
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    Las Vegas
    did the wire harness come with a new trigger assembly? if so it may be off spec from the stock assembly. Swap them and see if that fixes it.
     
  15. DreadCo526

    DreadCo526 New Member

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    Sylvester
    This might seem small but check and see if the selector plate spring is on as it should be. Take your gears out and see if the cut off lever can move freely, some times it will get hung up on the cut out of the gearbox(underneath the trigger contacts).