Puting the gearbox back together is no longer an issue. Now when I put it back together, it shoots a couple of times and it stops. So I open again, put it back together, shoot a couple of times and stop

It's obviously still an issue if it isn't working properly.

I'll have to agree and disagree with Mac at the same time. Sounds like you should just get a gun doc to do it. the $30 you spend will save you hours of frustration, and you'll have a working gun. A good way to learn how to work on a gearbox is to watch someone else do it properly.

Your descriptions of the problem are far too vague for anyone to diagnose through this thread.

Something occurred to me, after it stops, if you unhook the battery wait an hour put the battery (or better yet a different battery) in does it shoot a couple shots?

I agree that there are a ton of variables at this point and that he's dived in head-first. Not easy to troubleshoot your way out of a situation where you've accidentally displaced 7 things.

On the other hand it could be the battery :)

Yesterday I took it to a tech. He worked on it for 2 hours and dint find the problem. I was there and watched I'm work. He thought it was the triger contact that wasn't good. He changed that but still doing the same thing. And I put back the gearbox the same way he does. So it shoot a couple of times and the it stops. I open the gearbox, put it back together shoot a couple of times, and stops again. I took it apart like 15 times and ressemble it back but can't find the freaking problem. Ill try to unplug the battery and wait an hour or two and try again

Ill do the battery thing

Possible your battery mounts are coming loose from the motor from vibration? My CA did this had me baffeled for a bit. Another could be a bunk battery or needs to be charged.

If you fill out your location we might be able to direct towards a real gun doc

I did a continuity test on the electric wires. I did it from before the triger contact all the way to the battery connector. The negative wire has continuity. No for the positive wire to have continuity I need to press on triger so there is contact. No continuity on red wire. Opened the the gear box. Did continuity test on red wire and now there is continuity. Open box,
Check contiunit and now there is :s

Where are you located? Which gun tech did you take it to? I've seen a few people that call themselves gun techs but really are not good at what they do.

Okay so lets get this straight here.

-You opened the gearbox to change the spring
-You put it back together you had an FPS drop and a lot of misfeeding (wouldn't an FPS drop be expected after you change the spring...)
-You took it apart and put it back together and now it stops cycling after a few shots

When you say "stops working" do you mean it doesn't feed or it doesn't cycle?
How many is "a couple shots"?

It doesn't cycle. The motor stops working. Ill say from 1 to 10 shots and then it stops

Does it go completely dead, or does the motor still click?

What spring did you install?

Dead
Dead
Dead.
Spring 90

When it stops shooting, are you shooting in semi?