Need Help Bad! Classic Army V2 gearbox
 

I have a Classic Army V2 gearbox and the piston releases forward every 2 out of 3 shots. The anti-reversal is in correctly and engages before I put it together. I have no idea what else this could be.

Parts in the Gearbox are...

Stock VFC cylinder
Metal VFC ported piston head
Stock VFC Cylinder head
Stock VFC anti-reversal
Modify High Speed Ultra Piston
Stock VFC Metal Ball Bearing Spring Guide
Deepfire Metal Nozzle (M4)
Modify Enhanced Tappet Plate (V2)
Stock VFC Motor
Classic Army V2 Gearbox
Stock Classic Army Gears
Modify M110 Spring

Heres a video of whats going on

http://youtu.be/7AvzRNCzPl0

I could be wrong but it looks like if the gears and piston were binding up every few shots.

Maybe try shimming your pistonhead away from your piston, or did you shave the second last tooth?

I have shaved off the second last tooth

ok there are at least 2 things majorly wrong here:

1) Check that u actually have an antireversal latch in ur gearbox because if it's there it aint doin shit - u can see the piston back off after stalling out.

2) As mentioned above the piston is stalling out. this could be due to a multitude of reasons:
- ur motor is terrible (usual with stock motors)
- the spring in ur gun is too much for the motor battery combo
- ur battery is useless



ok so just in case u doubt my reasoning here - when u pull the trigger and it don't fire and then release the trigger and u hear the gears moving after releasing the trigger - thats ur gears reversing due to the piston being forced back the way it came - ur anti-reversal latch should stop that but it looks and sounds to me like u don't have one there.

also ur running stock gears with a high speed piston - i'm pretty sure that'll mess u up every time - think u need the modify speed set to key in properly with that piston rack.

my suggestions - upgrade ur motor (high torque) and reset and replace ur anti reversal. Replace the piston with a good standard version

nothing technically wrong with the gearbox - just badly set up so shud be pretty cheap fix

check if ARL spring is good, if not the ARL does not contact properly with the bevel gear.

High Speed pistons do not exist.
Modify call their piston "high speed" because it is from factory with the second teeth missing... which is good in any setup.

There is no ARL in the mechbox, if it's present, the spring is broken, missing or not locked in it.

Your gears do sound tight and your motor adjustment screw is probably too high.

If that was your first upgrade of a mechbox, reconsider having it done profesionnally. You would at least need a complete shim job, possibly a good greasing (I assume you cleaned the mechbox and used some good silicon-based or lithium-based grease on the mechanical components) and maybe a new ARL.