Hi all,
So a couple weeks back I decided to brush the dust off my g&g cm16. I have had the gearbox open before but decided I'd open it up, give it a clean and re-lubricate it, all was good, re-assembled and test fired. But during the process of re-assembly I had noticed the airseal was shocking, so ordered a new air nozzle and o-ring for my piston (was in two minds about going down a large upgrade route but decided for the cheaper option). A few days later my bits arrived, quickly test fired a couple times before disassembling to fit new parts, and the gearbox locked up. Dissassembled and could see through the cylinder port that the piston was locked to the rear. Did some shimming for the first time and have also been getting to know the inside of my gearbox a lot more (sounds intimate, I know).
I re-shimmed and assembled the gearbox without piston, spring, cylinder etc. and attempted to turn the gears with my finger. I noticed that the cut-off lever appeared to block the sector gear on a rotation, exactly at the point that the piston would be pretty much at the rear of the box. I tried a few adjustments and all was good, gears spun freely, no sticking point. Re-assembled and again the piston locked to the rear. Thought maybe my shimming job was potentially too tight, despite there being free up and down wiggle room, so removed a 0.1mm shim from each gear. Again gearbox stuck to the rear. I took the motor out, and spun the bevel gear with a screwdriver, after a few turns the piston shot to the front. This leads me to believe there is no physical block on the gears or pison (I can rule out the cut-off lever etc. as it is all standard internals minus the air nozzle). I thought the battery could be quite flat as I gave it a few hours charge when I initially went down this rabbit hole but never fully charged it.
Anyway enough of my waffling, the battery is currently on charge, and going to wait for it to recharge fully. If I am still getting gearbox lock up, after this, what would be people's recommendations I try next?
Thanks