AOSC Forum Archive

Ive got a wierd issue wiht my JG m4.  I just swapped the gearboxes out of my 2 m4s, and now when i put the motor back in, the gun doesnet do anything.  The wiring is ok, because if i take the motor out it operates normally.  the gearbox i put in the gun, is the one that was originally mated to the current motor.  any ideas on what the issue could be?

EDIT:  The gearbox was not opened or modified in anyway between removal and reinstallation.

Odds are you've either got a short in the wire somewhere, or the gears (and by extension the motor) are locked up. Pull the motor from the grip and trip the AR latch. If that fails, it's probably a short circuit.

would a short circuit still let the motor function outside of the gun tho?

Maybe its mounted too tight...I had that problem with my p90 awhile back. Adjusted the motor and it worked fine(until it broke of course)

Yeah, sounds like the motor could be too tight.  Did you run both wires up the back side of the grip?  If not, do that.  The motor should just fall into the grip.  If you have to push it down hard at all, it's too tight.

The motor fits snuggly, but does move on the spring.  and it wokred at the same height setting with the gearbox i just removed.  the only thing i havent checekd is wheter one of hte quick connects broke, and is onnly making contact when the gearbox iis removed because the wires arent bent as much

ok quick update.  the motor only doesnt function when the motor plate is on.  if i taek the plate off, tho its not making contact with the gears, it is functioning.  the AR latch is not an issue, as i was able to push hte motor down wiht my hand and the gun fired. but when the plate is placed back on and screwed down it no longers works.

If you wires were stripped at all and the hot feed is touching any metal piece (like the plate holding th motor in) it can cause some grounding issues which is why your motor wouldnt turn. I had the same problem on mine a while back.

The wires may be backwards, in which case you simply turn the motor 180 degrees and reconnect it, or the motor plate is shorting it, in which case you simply need to put a few well placed and thin strips of electrical tape on the inside of the motor plate in a manner that prevents it from shorting, but does not interfere with any function. If it isn't one of those two things, I'll give you a five dollar bill.

Dominum wrote: The wires may be backwards, in which case you simply turn the motor 180 degrees and reconnect it, or the motor plate is shorting it, in which case you simply need to put a few well placed and thin strips of electrical tape on the inside of the motor plate in a manner that prevents it from shorting, but does not interfere with any function. If it isn't one of those two things, I'll give you a five dollar bill.

It wasnt either of those.  It wasnt even the motor.  The piston had somehow jumped its timing.  The piston/spring was fully compressed, however the gearbox was still attempting to pull the spring back further.  Since it had nowhere to go, it was giving me the impression of no motor function.  Couldnt hear it hitting the back of the gearbox til i pulled hte box from the gun and hooked the motor back up.  Opened the gearbox and reset the piston timing and it work great now.  also gave me an excuse to clean and lube the gearbox finally

SteevoLS wrote: Odds are you've either got a short in the wire somewhere, or the gears (and by extension the motor) are locked up. Pull the motor from the grip and trip the AR latch. If that fails, it's probably a short circuit.

All you had to do was trip the anti-reversal latch, you didn't have to open it. The piston didn't slip or jump anything, the spring was simply fully compressed by it, and either the battery or the motor were not strong enough to complete the cycle from that point. If it happens again, trip the AR. In anycase, I owe you a five, hit me up at the next game.

yeah i tired too and couldnt get it to trip.  it needed to be cleaned anyway, so it was all good. 

as for the 5, ill see ya at cbw