ICS M4 seizing up

[doc_678]

Gun: ICS M4A1
Upgrades: metal piston, ics turbo 2000 motor, crane stock

Problem:
The problem began after I tried a 130% spring in the gun. I put the stock spring back into the gun and the problem continued (the stock spring is still in the gun). Basically the gun is not able to pull the piston back. The piston starts back and then stops and the whole gun seizes up. It chewed up the original plastic piston that was in the gun so I replaced that with a metal one. Then it chewed up the pinion gear on the motor which I replaced. I have tried an EG 700 and EG 1000 motor in the gun with no results. It’s currently running of a 9.6V battery so I even tried downgrading to 8.4V again no help. The gears turn just fine when the two halves of the mech box are separated. The shim job is definitely fine as is the greasing of the gears which has been done twice since this began. I also tried replacing all of the gears with some that I had around and still nothing. Also the piston can be pulled back manually with no apparent obstruction. For the life of me I can’t figure out anything else to try. Everything looks fine inside the gun so it’s hard to spot anything that might cause this. Any help would be appreciated. And please don’t tell me to go see the local gun doctor because I am it :P only relevent technical help please.

[wey ferro]

maybe the piston has different sized teeth on it then the gears.

[mcguyver]

how many mah rating is on your battery. if it's less than 1700mah then that would explain the problem with the upgraded spring, but it should run the stock spring fine. when you seperate the receiver, you should be able to easily turn the sector gear in it's normal rotation even with the motor connected. if you can't then there's a rolling resistance issue that needs to be sorted out (over-shimmed perhaps). now that you have also had a chewed up motor gear you may want to check your motor installation. as with some other brands (g&p to be specific), your motor wiring has a specific route it must take to allow your motor to sit correctly and not bind up due to improper gear meshing. the red and black must both go down the back of the handle, with the red on the same side of the gun as the selector switch and the black on the other side of the screw hole for the motor plate. then the black is connected first and the red goes around the top of motor to connect to the red motor terminal. this terminal should be on the front side of the handle close to the trigger. as with my g&p, my ics m4 was sensitive about wire routing and as you've tried different motors, it seems a logical place to start.

[doc_678]

Originally Posted by wey ferro

maybe the piston has different sized teeth on it then the gears.

nope same as stock

[doc_678]

sounds good man ill check the wires and see what happens. The battery is a 3300mah

Originally Posted by mcguyver

how many mah rating is on your battery. if it's less than 1700mah then that would explain the problem with the upgraded spring, but it should run the stock spring fine. when you seperate the receiver, you should be able to easily turn the sector gear in it's normal rotation even with the motor connected. if you can't then there's a rolling resistance issue that needs to be sorted out (over-shimmed perhaps). now that you have also had a chewed up motor gear you may want to check your motor installation. as with some other brands (g&p to be specific), your motor wiring has a specific route it must take to allow your motor to sit correctly and not bind up due to improper gear meshing. the red and black must both go down the back of the handle, with the red on the same side of the gun as the selector switch and the black on the other side of the screw hole for the motor plate. then the black is connected first and the red goes around the top of motor to connect to the red motor terminal. this terminal should be on the front side of the handle close to the trigger. as with my g&p, my ics m4 was sensitive about wire routing and as you've tried different motors, it seems a logical place to start.

[doc_678]

wires are fine. im starting to suspect the locking system for the mechbox halves. cuz the gears are not jamming at all on their own.

[mcguyver]

open the gear box, put in the battery and pull the trigger. do the gears turn at high speed with no signs of struggle? is the sound smooth or rough? from what you say there should be no reason for the gun to function.

if your gears turn fine it's not the locking mechanism. it will be in your upper gearbox. make sure your piston is aligned in the guide grooves and your spring guide is set in it's grooves properly.

[doc_678]

already done, gears spin at normal speed, no abnormal noises. I'll double check the spring guide but im pritty sure its ok too.

[doc_678]

thats the frustrating part about this is everything appears normal.

[mcguyver]

where are you located? there may be someone close to you who could look at it and probably figure it out right away.

btw, did you open the lower box and do anything in there? the anti reversal system is unique to ics and must be properly shimmed and installed?

[ert]

I'm going to take a stab at it and say check your wiring again. Was the gun wired to the front before you added the Crane stock? I am experiencing a similar problem with my ICS M4 and the problem lies in the motor height adjustment and the wiring I did to it. Maybe since I'm done school for a while I'll look into it more but the problem on mine is that it was wired to the front before and I rewired it to the back, but I must have put something together wrong because the motor height was messed up when I put it back together and now the motor has to be tightened all the way up for it to even try to pull the piston back and it does do it, but it sounds like crap. The problem on mine is for sure the wiring and reassembly I did to it.

[doc_678]

interesting. the thing is i installed the crane stock long ago and never had any trouble with the wires going to the back. I mean the wires are right in the groove that they are supposed to be in and they dont appear to obstruct the engine any. but i have noticed that if i screw the engine in all the way it will pull the piston back, but it does sound like crap as you said. so you must be right. ill start looking at that area

[doc_678]

if i figure it out ill let you know

[Greylocks]

If you tell people where you live in "Canada" (add that to your profile), then we'll be able to tell you to go to your nearest gun-doctor.
Diagnosis by email/message boards is a real pain.

[doc_678]

read the post i am the local gun doctor