I need help! I ran into a problem while putting my gearbox back together. I put my motor in and pulled the trigger, and only the bevel gear spun. At that point, all of my internals were together. To try and diagnose my problem, I took everything but the gears out. When I did that, they spun properly. I then put parts in one by one, but after i put my cylinder assembly, piston, and spring back in, only the bevel gear spun again. Does anyone know what the problem is?