Gearbox issues
 

Recently I upgraded the internals in my gearbox (gears, cylinder head, piston head, piston), when I put the whole gearbox back together (which is a G&G pneumatic blow-back) the piston would get stuck partway back, so I push the spring release and nothing happens. I pushed the piston all the way back with a thin screw driver from the air nozzle and it was stiff to push, and the spring release still did nothing. Finally I started to take apart the gearbox, starting with the metal piece that holds the top/back of the gearbox together and the piston moved slightly, I then pushed the spring release and the piston moved all the way forward slowly.
Could this be the piston is too wide for my gearbox or anything else?
Thanks!

almost sounds like the piston isn't on it's "rails" ... or the gears are shimmed WAY too tight...

What kind of lube did you use on the piston?

I have seen a couple of gearboxes where the owner used the chomo-moly gear grease on the piston rails and piston head.

threadjack; I've seen someone pour 5W-30 into a mechbox lol

You may need to physically modify your mechbox, or buy a new piston.
Many times I've seen aftermarket pistons get jammed in mechboxes simply due to tolerances. If you want to keep the piston, it's possible you might have to chisel down the piston rails to get more clearance

Yeah, I've already came across this too, once the customer didn't put the piston in it's rail, or on one of my first guns I had an hexagon type piston (G&G) and the new modify one was round, thus needed some exterior trimming so it wouldn't jam in the back of the gearbox. Also, did you pay attention to reshim the gears properly, as Reckless stated.

It's a Hurricane piston, I'm almost certain the piston is on it's track, I think it might be the shimming. I'll have a look when our A/C get's hooked up (idiots forgot their manual so I've gotta wait till tomorrow), this heat really makes me not want to do anything.
As for grease, it's legit gear grease, don't remember what kind because my friend has it right now, but it was used on the piston grease rails and piston head...
I'd buy you all a beer for the help ;)

Be aware I'm not too far from you, and we might see each other once in a game, I shall ask you for that one :D Hehe JK, hope to see you on the field soon!

The only games I've played so far have been at Airsoft Rawdon, if I can't get my gearbox to work, perhaps I could send it to you then?

We can arrange that for sure! There's a game on the 23 near Trois-Rivières, I could check that out for you :)

Moly gear grease is too thick to be used for compression, and it's gums up with dirt really quickly. You need to use something lighter and cleaner like synthetic grease.

+1 Internetz for me. I'd love a beer too.

Clean that gunk out of the gearbox. Find a nice tube of Anal lube or food safe silicon grease to put on your piston rails.

I thought of the anal lube...But I don't have any...And if I did, I'd have better uses for that ;)