Ics m4 not 'cycling' proper

[ghostwalker]

Having addressed the problems with my l86. I now turn my attention to my ics m4.

It's a little hard to explain the issue and if a video would be more help please say so.

My m4 has an erratic problem with the way it seems to cycle (not on a bike I might mention).

When you pull the trigger on occasion it will fire and cycle fine, but then for no apparent reason it will stop. When the trigger is pulled you can hear the gears/motor turn, but it's almost like the whole cycle doesn't complete and there is no 'release' or 'pop' of the gun firing. If you pull the trigger further times, there will be a click but no movement action.

If you then press the forward assist button, you will hear the gears release. The gun will then either shoot or start the problem again with the sound of a 'half' cycle and then nothing.

I tried replacing the fuse, a fully charged battery, changed out the spring and piston. But none of these have helped.

I'm not the most familiar with m4's but trying to learn and trying to sort this out before surrendering it to a tech.

Any advice muchly appreciated.

 

[Samurai]

Make sure you always fully pull the trigger and wait for the single shot cycle to end. If you don't, then the gears might stop in a position where the cutoff is half raised and the trigger trolley hits it when moving forward, and it jumps off the trigger before closing the circuit. Switching to auto (raising the cutoff) or releasing the spring (moving the gears from this position) fixes it.

 

[ghostwalker]

Unfortunately switching to auto doesn't have any impact.

When the gun 'locks' it won't fire in any mode either semi or auto.

Using the forward assist button releases the gears, but that rarely seems to help, as once you pull the trigger again, the gun will just go through the 'half cycle' and lock again. It's almost as if the piston is pulling back and then not releasing forward.

 

[slick]

open it up and separate the upper from the lower, pull the trigger, does the lower spin freely?

 

[Sitting Duck]

could be a number of things.....

could be mechanical but I think I'd try another motor or at least check connections are sound fit

if it is old & well used possible carbon build on motor

but could be on trigger contacts

might be mechanical - heck a tiny little chip of plastic from piston let alone a particle of metal will force a lockup

yes could be mechanical but I'd have a quick look at motor connections and actual motor itself whilst you about it

could be carbon or burnt trigger contacts perhaps but I'd check all stuff like motor plus examine wiring first before you dive in deeper

reckon running just lower box will spin quite freely coz no load on box but if a bit of crap in there it may still lock up

but think with no load she will turn over very easily....

I tend to think ICS motors are a bit quicker than most stock motors but perhaps not quite so robustly built

Think Lord Metile had a motor play up and needed replacing think under warranty

and also I've had an ICS just dead as dodo, but seperated the two halves and she ran fine,

reassembled the top part - no gears showing when you replace the 2 x halves

She ran fine again ??? - bloody weird but think to this day that maybe motor might have had a dead spot in it

(though this can happen to really any motor me thinks - a break in wire wrapped around armature - zilch from motor at that exact point)

Not slating ICS motors but think maybe the motor or windings "might" not be highly robust of built like others

no doubt my guess is gonna be totally wrong but I'd check out that motor & wiring first, maybe another motor to test

if still no joy....

Just ADS & shout BANG or Peew Peew, soz I mean let us know how you get on

 

[ghostwalker]

Will give it a try later today.

Wire up the battery, open the receiver, pull trigger and see.

 

[Samurai]

Worn trigger trolley / trigger might also cause this.

 

[ghostwalker]

Did as asked above and separated the upper and lower and cycled the gun.

The gears appear to move freely though in semi though some cycles seem a little 'shorter' than others. One thing I picked up was that every once in a while the cycle would go into 'full auto' and keep spinning until the trigger was released, despite the selector being set to semi.

 

[slick]

If you're not confident to open up the lower gear box it will probably need a tech.

As above sounds like trigger contacts, or worn cut off assembly.

If you have worn/burn contact make be worth getting a mosfet fitted while it is opened up.

 

[ghostwalker]

Made an attempt at a video to better demonstrate the problem.

I'm happy to have a go at sorting issues out. Not the most experienced, but you can only learn by doing eh.

 

[slick]

sure your battery is ok?

 

[ghostwalker]

Have tried several batteries, it nearly or even possibly killed one by over heating it. But hasn't repeated that trick thankfully.

I have tried both an 8.4 and 9.6v 1600mah Nimh battery

 

[Sitting Duck]

Have tried several batteries, it nearly or even possibly killed one by over heating it. But hasn't repeated that trick thankfully.

I have tried both an 8.4 and 9.6v 1600mah Nimh battery

Overheating is lockup issue

Trigger cut off problem is sporadic cycling issue

You got 2 issues me thinks, doubt if motor fault

But avoid slow light trigger pulls as it won't pop on semi if cut off don't get under trolley properly when slow light pull

If trigger and trolley jump off then trolley tab worn but seems OK on auto. So cut off trolley lug is most likely the cycle problem with just lower receiver

Wonder if any parts fitted were not quite fully compatible with the ICS box, any history as to what or where you got it from. Some bits need checking when fitting to double check they operate 101% as they should in each box

Just wondering how/when gun developed this fault on cycling or had been forced in dead zone in the past ??

Locking up - hmmm something else but let's try and solve one issue at a time - that locking up could be another bit failing inside

Think no matter what it is gonna be strip down no matter what I'm afraid and close examination when rebuilding

Nothing too major but not a simple fix

Minor rebuild for a tech if you don't fancy it

 

[ghostwalker]

Unfortunately the gun came from a friend and he hasn't used it in a while as he fell back on his back up of a kings arms fal.

The only internal changes were a replacement piston. But that was a stock ics piston. The other changes are all external cosmetic ones.

I have a spare selector plate for the gun as he thought that was the cause, but hadn't got around to replacing it. As for the rest?would a new lower gear box be the easiest answer in reality?

 

[Samurai]

It looks like the motor can't pull the spring. Even without the upper it looks to work very slow. Can be motor, wires, very bad shimming, motor height, battery, etc.

 

[Sitting Duck]

As for the rest?would a new lower gear box be the easiest answer in reality?

No in a word.....

you still might have the lock up issue - yes it could be motor but until you try another motor in it we are all going to be taking at best a calculated stab at things

The cycling is still not quite right either

you got 2 different issues but tbh a complete overhaul or service is very likely what she will need to get in there and check EVERYTHING

one problem is much easier to pinpoint but even so I think it is due for an overhaul if it is old & a bit worn in places

Yes you could chuck in "another" lower box but by the time you done that - you gotta remove old box anyway

so may as look at investigating and fixing old one - might take time but gun ain't working correctly atm

plus buying another s/hand lower box - may end up with a lemony box like you already got

It will need opening up - but due to split design at least you won't have spring exploding on ya like a normal box

yes still AR latch but main spring isn't there on lower box so chance of usual KABOOM - f*ck where the heck did that tiny bit go.... is reduced

as long as you keep gears n shims exactly as they were you won't screw up the shimming

though to be fair - that is taking it as shimming is about right - which might not be prefect but hopefully "reasonably ok-ish" if not been messed with too much

It is up to you - you could venture further yourself

or send it off to be diagnosed and serviced quickly by a good tech

sadly finding a good tech who doesn't charge the earth but offers a trusted service built upon years of wisdom & experience is not so easy

Yes there are very experienced people like in all walks of life - but they don't offer their wisdom for free

As it is ICS - you might wish to speak to Fire Support as they are the experts for ICS and if anybody should know their $hit it is them

Failing that you got f*ck all to lose really by ripping her open yourself - it ain't working at all really with lockup n cycling issue

if you screw up you can decide to source another box or bits or spare/repair ics gun

or cut your losses and sell as a spares repair project

Don't think it is much to sort out but needs to be stripped down to get to the real issues I'm afraid

only then will anybody really know the exact flaw in the poor thing atm

hope some of bollox helps you to decide your next move

 

[ghostwalker]

Lol thanks for the advice. I will probably pull the gun down myself and see if anything is obvious.

will probably use an enormous amount of Google-foo and you tube time. But hey, best way to learn is to do.

Was thinking about turning this into a DMR if that's even possible. So having it in pieces will give me a good starting point lol.

Though I am lead to believe the gears in the ics box should be upto that, but probably not the motor/cylinder/piston/head/nozzle and Spring.

Whole new line of thought, but figure if it's getting an overhaul, might as well do it all at once