WE Katana Help

Discussion in 'Gun Building, Modifications & Repairs' started by DusterCP, May 17, 2018.

  1. DusterCP

    DusterCP New Member

    Hey guys, this is a complicated one so bare with me. So I Have a WE Katana M4A1 Series, Second hand as a restoration project. I have recently replaces Hopup entire cylinder and gears. however I am currently having the issue of only every second pellet will feed. as well as this sometime power cuts out completely and come back randomly with no warning, I feel I have deduced it down to 1 or more of three things The battery (which is dodgey but unlikely as my mosfet shows its receiving power, when miss firing anyway), the wiring between mosfet and motor (I'm kinda unsure about this because I can properly access the motor, because WE} and the Motor it self (which again I cant really check with the tools I have) I am willing to send it to be repaired but I want to isolate the issue first, any tips about what I can do to find out or and conclusion anyone may have drawn or even local places to west sussex (southern England) where I can get this repaired as many repair shops stay well clear of Katanas. Thanks a lot [​IMG]
  2. Honeybadgerz17

    Honeybadgerz17 Active Member

    the first issue sounds like tappet timing, and the second might be a problem with a wire short, you could check this with a multimeter

  3. cetane

    cetane Active Member

    Markham & Stouffville, Ontario, Canada
    No tappet plate on the we katana. Uses ptw style loading.

    Misfeed could be mag related, but if using hicap mags very unlikely. More likely the urethane oring on the piston head that grabs the nozzle to allow feeding is tired, so it isn’t “gripping” the nozzle properly to be retracted well. You can check that by removing the cylinder head cap and by hand work the action and see if the nozzle is releasing from the piston head before you feel the piston head stop moving on the piston body.

    As for the motor issue, pop the grip plate off and see/feel if the motor plugs are snug on the blades. If they’re too loose, that very well could be your issue.

    The katana is easy to work on. Lower half just like a v2 to work on other than the spring release stuff with the selector (mine currently has none of that or an arl :-/)

    The cylinder is simple enough. Most of your wear components in it are the piston head itself.

    Mine has a 15t shs ptw piston in it along with the original piston head & silver cylinder. My lower has some acm 14:1 gears ss1 pulling the m130 well on the stock neo we motor with 11.1 20-40c or 25-50c batteries through a gen 1 ascu I found in my parts box I had forgot I had lol
  4. BOA_SP3CT3R

    BOA_SP3CT3R Well-Known Member

    Bull Shoals
    It sounds like a very interesting system. IIRC didn't you say a while ago that they have very consistent FPS?