Gearbox shimming problems.

[Undieing_Lust]

So I need help with shimming my gearbox on my ICS CXP M4. This is only the second time I have ever shimmed a gearbox and it went fine last time. But I have run into a little problem. I followed this guide:

 

http://airsofttutorials.com/tutorials/shimming.html

 

The Problem I am having is the gearbox whines really loud. I have tried adjusting the motor height and the noise is still there. Also the trigger locks up and I have to put it into safety to reset the trigger, and the motorplate has cracked on me so am waiting for a newone to arrive. untill such time I cant test the gun.

 

[straffham]

If the motor keeper plate has snapped it sounds as if the pinion gear is too tight against the bevel gear, preventing the motor moving into the gearbox sufficiently, which could also explain the whining. I usually just fit one shim on top of the bevel gear, which allows the motor the maximum amount of travel and I find, gives the best gear mesh. Other than that Did the gears all spin freely with the gearbox closed up? Could be the spur gear is tight against the sector gear so may need shims swapping around?

[Undieing_Lust]

No I spined them before I closed up the gearbox and there was no grinding and they spined freely.

 

(edit) By closed up I mean back into the receiver. I screwed down the gearbox and they spined freely

[straffham]

Sounds like the issue is the pinion to bevel gear interface being too tight or even not meshing properly from what you say? Or could be the motor sticking in the grip, due to wiring possibly, and not going far enough into the gearbox? If the base plate snapped when screwing back onto the grip it sounds like the problem is that.

[Undieing_Lust]

Sounds like the issue is the pinion to bevel gear interface being too tight or even not meshing properly from what you say? Or could be the motor sticking in the grip, due to wiring possibly, and not going far enough into the gearbox? If the base plate snapped when screwing back onto the grip it sounds like the problem is that.

Ok I think I will see about moving from shims from the top of the bevel gear to the bottom and also when the next grip/baseplate arrives make sure the wires are not in the way. Any Idea why the trigger locks up?

[straffham]

Not off the top of my head, could be an issue with the cut off lever, or more likely the trigger is slightly out contacting thetrigger switch. I've had that problem, way to tell is when you pull the trigger without a battery connected, if it clicks its not seated properly, it should just move smoothely and quietly, though I've not had issues of the trigger janming

[Undieing_Lust]

Not off the top of my head, could be an issue with the cut off lever, or more likely the trigger is slightly out contacting thetrigger switch. I've had that problem, way to tell is when you pull the trigger without a battery connected, if it clicks its not seated properly, it should just move smoothely and quietly, though I've not had issues of the trigger janming

It just moves back smoothly...

[straffham]

Strange. . . . So the trigger physically locks back each time you pull it? On semi or auto, or both?

[Undieing_Lust]

Strange. . . . So the trigger physically locks back each time you pull it? On semi or auto, or both?

Both. but that is only with battery and motor in. with out those the trigger pull is smooth...

[straffham]

Is the small spring that pulls the switch away from the contacts working OK, and the trigger main spring seated properly?

[Undieing_Lust]

I check the trigger spring and the smaller spring and both worked fine...I think am just going to have to wait untill the new parts arrive and test again....