ICS Gearbox not coming together correctly

[venture]

I have searched for this but to no avail. I have to refer this to my ASC colleagues.

I just repaired an ICS M4A1 for a customer. I put a new tinted lower from Alberta Airsoft, a new trigger mechanism and a new 140% spring.

Now when I reassemble and put the upper and lower together the sector gear teeth will not reach the piston. They just turn and turn. I noticed that the stock ICS piston was worn a bit so I put a brand new piston in and it still does not reach the piston gears. Also I can't get the body pin in very well.

Could the new trigger mech be causing the gearbox halves to not quite mesh properly?

[HKGhost]

When you say the gear and piston don't reach, is the gearbox is fully closed? That seems really weird. I notice if you tighten the lower gearbox too much, this cause the upper to not fully seat into the lower. Use loctight and don't torque the screws. Remove the grip and motor completely and then install the two halves. This could be the cause.

[PHARAOH]

from my experience owning and fixing ICS split gearbox's, i would suggest that you buy the steel full tooth piston, and keep the stock ICS sector gear.

i know that when i tried to upgrade with full TM/compatible parts they just didnt work until the piston was full tooth and the sector was stock ICS.


hope this helps.

[venture]

I think you hit it right, ghost. The screws in the gb were torqued too much. I can now pinpoint the problem. I know exactly what was happening. That little block thingy in the front part of the lower gb could not move because that front screw was too tight. So it is that front screw in particular that cannot be torqued too much. When I released that screw a half turn the little block could spring down easily when the upper gb pushed it. Without that thing being able to swing down the gb was not going together properly.

[HKGhost]

No problem Ron. I had the same problem when I was working on one. If the rear screws of the lower gearbox is too tight, you'll never be able to close the two half's. And for the body pins, remove the grip like I posted and put the pins in before the grip and motor.

[Rooster]

Yeah I did the same thing when I put a new trigger set up in mine Ron.. Tightened that front screw too much the block couldn't move so it wouldn't close.. half a turn backed off and it popped into place nicely.