m4 S-System missfiring.

[Rechkalov7]

Greetings,


i recently bought a jg m4 s-system to find out that the motor is stopping in full auto after a few shots. It's shooting properly in semi auto but not in full. I have a feeling it's not hop-up related at all because it's the motor itself that stops. Funny thing is i tried the rifle with some other battery i know is fully charged and workd well with a top notch Airsoft. Another thing, when i dry fire it and shoot full auto horizontally, it stops randomly but as soon as i put the rifle vertically like for shooting in the air the problem stops. Any help on this. Ive been looking around many forums and still haven't found the solution. Anyone willing to help a little would once again be greatly appreciated.




Thnaks.

[cetane]

Kinda sounds like maybe a loose connection somewhere. Next time it stops, give the bottom of the motor plate a smack with your hand. If it starts working could be a loose connection at motor

[Wrath144]

Does indeed sound like a motor connection. Take the outer two screws off the bottom of the grip and make sure the two wires are securely connected to the motor.

[Rechkalov7]

Hi,

i've got a feeling it's either the battery who's not giving enough power to the motor or the motor who's not strong enough. The motor itself seems pretty beefy but who knows. About the connections it's not screws in the grip it's just metal sleever that makes 90 degrees and connect into flat pins. I don,t know about that it seems to be pretty ok. There must be a logical mechanical reason for the motor to run normally when the barrel points in the air. I'll keep searching and rewire everything to make sure the connections are ok. It looks more like a lack of power to me.

[Sha Do]

If you strongly believe that your issue is battery relaited, there are several things that could be the cause;
-there could be a break in a wire, or bad solder at one of the contacts which would cause a point of resistance
-the box could be shimmed too tight, again causing resistance
-the motor could be weak or burnt out
Remember that bad wiring and points of unnessicarry resistance increases the mah needed to cycle AEGs to increase dramatically, and depending on your battery size, mah, and the power of the spring, this may be dififcult to trouble shoot this issue via on line.

SHA DO

[Rechkalov7]

This why i will never go cheap again. I sometimes like to work around things and make them work but in this case it could be almost anything as you said.

[Rechkalov7]

Hi,


one more thing, if it fires perfectly in semi auto does that mean we can eliminate wiring problems?

[CerberusNet]

A few theories..Hopefully atleast one helps to solve the issue.

Please try these steps safely..
(1)In a secure area, get your rifle ready to fire (Pending internals you may be able to dryfire) and select semi, let a cycle go. Try not to move the rifle too abruptly and select auto and let a few cycles go. If all is working properly reposition and retry(1b). (Aim in another angle)
(1a)If auto fire stops while firing, carefully move the handle towards ear and listen for any noise, while depressing and releasing trigger. If you hear a faint clicking or rubbing, the connection is fine and there is a problem in the mechbox. However, because you had mentioned that semi fire properly, I believe a problem in the mechbox would hinder this ability..So that exercise may be a waste of time but would be good to rule out.
(1b)If no noise is heard from excercise 1a, it is most likely a connection or wiring issue, either to the motor, the battery, or the triggerbox. This type of issue would create ressistance and ware out your battery prematurely, as stated by Sha Do above. You will now need to test each connection. If you find any exposed wiring please do not follow the steps below untill wiring is covered and safe to handle. Normally a current testing kit would be ideal, but most likely unavailable. You may want to open the housing for the battery and move the wires slightly while depressing the trigger in full auto. If no difference, you will then need to disasemble and check connections and wiring throughtout the mechbox, triggerbox, and down to the motor. If any problems are found, assuming you are knowledgeable in wiring and electrical currents, you already know what to do. If you are unfamiliar please do not proceed and seek assisstance as this could be dangerous because of possible electrical discharge.
If no problems are found in wiring or connections, there are a few other ideas..

(2)Power- you may have a battery that has insufficient power. Either because of long term use/abuse or it just isn't the proper battery. Try a newer battery of equal power, or a newer one of greater power and test the performance.

(3)Motor may also be on its last legs and either due to long life or prior wear and tear or abuse may need to be replaced or repaired.

I've lost my train of thought...Hopefully what I've provided is helpful. I apologize for the lenghty explaination, but it is a difficult problem. I've had identical one with 100% of my older armalites. If you're unfamiliar with these methods I would be happy to do the work for you. Just contact me for details, or one of the many gundocs on the sticky thread "Calling all gun docs" you should be able to find one in your area.

[Rechkalov7]

Well,

thank you so much for taking your time to try solve this problem. You wouldn,t be a writter by the way?