Screeching Gearbox

[krazy_horse]

Hi folks,

My G&P M4 variant g/box started screeching when i was using it a few weeks back so i decided to take the gun apart and have a look.

I found that the motor bevel gear has become damaged and there are quite a few teeth that have some damage. I opened up the gearbox and everything looks ok in there.

Can anyone tell me why this problem may have arisen? I have tried a G&G motor in the gun as well and it still makes a similar noise. The gun still operates and fires, but it just has the annoying screeching sound and i fear i will do more damage if i continue to use it like it is.

Does anyone know what may have caused this?

Cheers,

JB

[The Keeper of Secrets]

Re: Screeching Gearbox

Chances are the motor height was very badly adjusted. The general rules goes with:

Too loose (far from gearbox) gives a high pitched screech.
Too tight (close to gearbox) gives a low grind and ROF slow.

Best thing to do, replace your beve gear, readjust your motor height. If it still screeches, have a look at reshimming and cleaning your gearbox.

[johnnyj]

Re: Screeching Gearbox

My first thorght would be motor hight was incorrect

do the gears all spin free with little movement on there axle's when the shell is closed

[UnionJack87]

Re: Screeching Gearbox

I had the exact same problem on my BoyI SCAR last week. 1 turn of the adjustment screw on the bottom of the pistol grip and now its perfect again.

Hope this helps

[magic_golem]

Re: Screeching Gearbox

um do you mean the gear thats on the motor shaft? i thought that was a pinion gear and the bevel is the one that it meshes with, or have i been getting it wrong for ages? :p

[The Keeper of Secrets]

Re: Screeching Gearbox

No you're correct. The pinion gear is the small one on the motor shaft, then it's bevel, spur and sector in ascending order.