Could it be the Motor?

[Payback]

I'm working on a G&G m4 gr16. It's a new gun, used once at a game. At that game the thing went full auto on semi, full auto with the trigger let off, then started smoking when it was layed down at the end of the game.

I've put in a new trigger with low resistance wires, tweeked the cutoff lever and the springs to get it to work. All shoots now...... for a bit.

When i test fire the gun, after about 50 rounds the battery gets warm, not hot, but warm, then the gun just stops shooting, you wait about 1 minute, then shoot again, then nothing. rinse and repeat.

Also, i hook one of my 9.6v batteries, and the motor wont turn, i hook up another one and it will turn/shoot. But when i hook up the first battery in any of my other guns, it works just fine.


Could this be a motor going bad? Even on a new gun with about 5k rounds through it? Any help or ideas on what the problem is would help. Thanks.

[Cloudyrains]

Check to see if the wire is getting hot. Could be a short/too low gauge of wire. Also, is your battery working in other guns after you shoot it in your m4?

[Payback]

The wire is warm near the battery, the wires near the motor get hot also. But the wire is supposed to be low resistance wire, but it is a small gauge around 16 gauge i think. The batteries work in all other guns after it doesn't work in this one.

[Hitokiri1597]

A bad motor is a possibility, I've got 3 bad motors out of brand new Combat Machines sitting on my tech desk, if you've got a spare motor kicking around throw it in and see how it goes.

[Switchback]

Make sure your motor wires are on the correct terminals.

Maybe you have some frayed wires somewhere between battery and motor.

[Variable]

Years ago people could get good troubleshooting advice on AP. Then most of the experienced airsmiths got burned out answering the same shit over and over.

Anyways.

It sounds like your motor is indeed overheating. You need to find out WHY its overheating. You could throw parts at it, but the simplest explanation for a motor overheating like that is that you have the gearbox shimmed wrong.

Good luck.

[Payback]

Well, the search function on here sucks. I can sit and spend hours searching through the worthless questions that burned out the airsmiths and never find a decent fit to my problem, or simply ask a new one and hope it gets some reply's. I did find a few things that i tried before i posted tho, checked shims to make sure they aren't too high, fixed alignment issues with the cutoff lever.

I've checked the shims, removed some to make it loose again, it was shimmed and spun easily with the gearbox screwed together and tight, but still removed some just in case.

I put a new wire set in the gun, and pulled a motor out of another gun that is a high torque motor and tested it. that seemed to fix it for now. I still need to run it through the paces more.

I put the old motor in the other gun that worked fine and it heated up within 500 rounds. So i'm going to guess that the motor is what went bad.

[G36 FTW]

The combat machine motors are pretty shitty. The one I ripped out of my sport line G&G MP5 was a piece of junk, and was replaced by a stock JG motor witch was 4x better than the G&G (weird aye?).

So, yea. Probably the motor.

[CommieHunter]

It's way easier when you own multiple guns.

Yes, it sounds like your motor is overheating. I would try replacing it if you have already tried re-shimming and are confident it is correct. If you had a 2nd gun, you could pull the motor and try it without buying a new one.

However, it seems like a new motor would probably be a good bet.

[Payback]

I'm calling this gun fixed. One way or the other.


I did have another gun that was a loaner with a high torque motor in it, did the swap, it works. I put the old motor in the other gun and re created the same problem. I think part of it was the cut off lever and the spring for it not letting pop back into it's semi auto setting. He went to the outlet and got a new trigger with a shorter spring and it worked well.

When i shimmed it and double checked the shim they spun freely with it screwed together with little side to side movement. I also saw a post that said to make sure i didn't shim too high, and had 1 thin shim on the bottom of the sector gear and spur gear.

[Bircher]

I have the GR15 raider XL, is yours the 16 because Im nervous now...

[Payback]

It isn't mine, just a team members, but yes it's the xl with the long metal rail. I also have one that was the asgi g4 series that had a similar problem with the trigger and cut off lever, but the motor was upgraded so it was fine.