GR25 Electrical Issues

[ujiro]

So, randomly at the last game I was at, my GR25 stopped firing.

Went home and cracked it open. Rechecked all connections, everything was good. Checked battery, battery was good, still outputting full voltage and current.

But it won't fire. No noise, no nothing. Took the mechbox out, and manually set the selector plate to semi and full auto, and pulled the trigger, seeing if the motor would even turn. Nothing.

Then even checked voltage across the motor, and current going into motor when the trigger was pulled. Both came up zero.

I am thinking switch assembly issue. Anybody else got any insight?

[Donster]

is the motor fried? perhaps you have to replace that.

[ujiro]

Could be it.. I'll have to check.


**EDIT However, forgot to mention I tried to use another motor too, and it also didn't work. However, I cannot remember if this motor was functional either, but IIRC it was.

[Donster]

than it sounds like a connection issue i should think. perhaps the connectors have carbon scoring or w.e its called that is causing them to not make a proper connection.

[ujiro]

Wiring is all brand new (looks brand new though). I haven't opened the mechbox yet to check any connections on the inside. But the connections between battery and gun are brand new, and the connections to the motor appear pristine... Hmm..

[m102404]

When you've got it open, take a close look at the switch assembly fins. If they're spread far apart, squeeze them back together with pliers...nothing crazy, just enough to ensure good switch contact.

You can hook up the motor "loose" on the table and test out the electrical before putting it all back together.

Tys

[ujiro]

Well, took it apart. There was a small rectangular piece of metal sitting randomly in the gearbox near the switch assembly.. But the fins were good. Tested pushing the sliding contact into the fins and it was good. Put it back together, closed up the gearbox and shot. It worked for about 4 cycles, then right again stopped working.

When I took it apart the switch assembly seemed.. weird. The piece that moves when pushed by the trigger seemed off a bit. I had to push it into proper position. If I removed the trigger, the spring was pulling it off center, and would not slide. With the trigger in this would stop the trigger from even being able to move, unless I pushed it in properly, then pulled the trigger a bit then released it so that it would catch on the trigger.


Anybody have an idea what that rectangular piece of metal could be?

[m102404]

I think that you're referring to the block just above the purple part H:


I refer to it as the switch block. Both the rear and the left side of it can get worn. Also, the main switch assembly (the purple part) can get messed up (either inserted or screw in wrong, heated up and warped or the fins can get burned out) can go funky.

Usually, it's not worth throubleshooting...just toss it and get a new one. It's a pain...since you have to rewire. Or if you're sure your wiring is 100%...desolder it from the old switch and solder it onto the new switch.

Best of luck!

Tys

[ujiro]

Yeah considering switch assemblies aren't that expensive. It is a problem within the switch (I took a look at the gearbox surrounding it, not a single issue). So something has broken on the switch assembly and it will not stay in proper place. Oh well, time to replace it. I am sure the wiring is 100%, so I am just going to desolder and resolder it onto a new switch.

Any advice as to your favourite switches, m102404?

[m102404]

My favourite ones are the ones that works...I could care less what brand it is.

Honestly, usually I have either G&P or Guarder switch assemblies on hand...so in they go when needed.

Completely honestly it's whatever http://www.airsoftparts.ca has in stock...Jugglez is tops and is just down the street from me.

Best of luck,

Tys

[ujiro]

Hah, sweet. Okay thanks Tys. You've been helpful.

[SEALs]

Hey big guy, I had the same problem which kept my GR-25 from being field for 2 years, nobody couldnt find the problem and I always had same syptoms has you. Cycles for a few shots then nothing, gearbox just seemed to have died. At first, I thought it was the motor or shimming and I found that it was even more simple than that. For I dont know what reason, the GR25 gearbox is very sensible (porbably due to the fact that it is a semi auto only) You know those nasty little springs? The tappet plate and contact switch seemed to be the issue. They have specific way to install them if you fail to do so, you'll experience gearbox misfunctions.