GFC GF25

uniweekendwarrior said:
Contacts are not touching 
Click to expand...
Click to shrink...


F*CK ME X 1,000 etc....

Time to get a test meter out and check EXACTLY where the short is then

I'd say the switch itself is suspect BUT remember the selector must contact the prongs when testing

(In safe it will break the circuit)

"maybe" the switch or wires is shorting on the gearbox shell itself somewhere ???

BUT if the short took place elsewhere the gun would fire on safe I would have thought

Also though I suspect the short in the vicinity of the trigger - who knows as it has been rewired ??

If the mosfet failed - why didn't somebody just replace the mosfet ???

So has the rewire been done 101% correctly or was a short causing the mosfet to blow or give the impression the mosfet died

I personally would perhaps at some point consider desoldering the wires at switch and thoroughly testing switch then wires seperately

Then once pinpointing where the short is happening look to replace switch or wire

It does seem the switch is the area to investigate as the selector plate and semi but not in safe

It has to be around that area to me.....

See if the two wires - silver & red had a wafer thin join shorting them it would fire in safe

if the prongs were shorted it wouldn't fire until contacts bridged

So in my mind them damn contacts must be bridged somehow ???

was the switch removed and rewired/soldered when removing the mosfet wiring ???

Somewhere that trigger switch is pear shaped in my book

Might need to check out the wiring and get a new trigger switch

perhaps a non prong shs switch but keep copper on selector even though not needed

YES it is a JG v2.5 with jumbo cylinder head and std cylinder it seems than the longer cylinder/piston

WTF do makers do this - you even got the std 16 tooth sector than the 19 tooth sector

poxy ar$ey gearbox - just extending a friggin v2 but not doing it with longer teeth/piston

They just slopped a jumbo length cylinder head instead ffs

As for this electrical issue - I'm starting to think...

You don't need a tech - you need either a coroner to do an autopsy

or

a friggin' priest coz the bastid gun seems possessed by some weird dark spirits

 
Last edited by a moderator:
uniweekendwarrior said:
View attachment 27088
Click to expand...
Click to shrink...


The only weird thing I can come up atm that the spring on the safety arm is coming into contact with red wire

but the silver wire would have to touching the metal box making it live for a short to take place or something ???

You could try to flatten that red wire down a bit though it looks like it should clear under the spring

But it looks like it might be clear just about and spring/arm does sit a good few mm above

Though there is a raised hump a little further back....

As the mosfet got removed - probably was a $hite cheapo one that blows as soon as it goes above 10amp

When the mosfet was removed and rewired, something likely went tits on the rewire & resoldering at switch

Tell you what is a little strange though - that switch

Not so much the black & white mix of it so much - had a black trolley in a white switch or vice versa in a gun or two - though it is a bit weird that you got black switch contact body with a white end cap. Should be all white I think on JG stuff that I found....

JG-Mosfet-Wire-Set-M76-2.jpg


So wondering if the switch unit is now a bit of a mish mash of bits n bobs though it looks like end cap fits

Does raise some concerns though about just how well it was modified/rewired after mosfet removal

BUT - it is a but coz it is a bit hard to make out in pic....

By the silver wire solder joint, the tab it solders to seem to be at the back or right of switch in picture

The soldered tab is sandwiched between the black & white and looks OK

HOWEVER - there is a bit of copper right above the main blob of solder - this likely the other copper track

Is it bridged at all coz this would be the two tracks of the contacts and would be the same as the trolley stuck in contacts....

oqgR1BV.jpg


That switch looks suspect - a short is taking place there at some point but hard to see and figure out in pics

Yes those china mosfets are $hite, a decent pico ssr3 or Fire-Storm or heck knock your own 3034 for under a fiver are miles better. If the mosfet crapped out, it would have been easier to replace the mosfet - even a Gate nano whould have been fine, any bit of resoldering wouldn't have mattered coz the gun needed redoing when rewiring back to std non-mosfet wiring

 
Last edited by a moderator:
Does it spin if you remove the pistol grip's bottom plate?

 
Samurai said:
Does it spin if you remove the pistol grip's bottom plate?
Click to expand...
Click to shrink...


It could be a conventional short but on safe it doesn't fire due to prongs etc....

(well from what I can make out)

which if it was shorting on the two positive leads between motor & switch it would fire regardless of safe

Yes the motor plate or crushed wires but that mish mash switch, the old mosfet removed/rewired

plus the gun is safe but goes nutz on semi is pointing to short somewhere around the switch area

needs a priest with a testmeter to look at this I think or drown it in holy water

The trouble is when people list a fault or issue it often transpires to be something very different...

uniweekendwarrior said:
Hi all,

My mate dropped me off his GFC GF25, I'm guessing their version of the sr25 dmr. The fault with it being it's stuck on full auto. So I'm taking it apart and I get to the selector switch and I'm stuck. On my other rifles there is a screw on the switch to remove it. How do I remove the switch from the GFC.? 

Tia 
Click to expand...
Click to shrink...


See - the original post might have indicated an issue with selector plate or a worn Cut Off Lever not popping the trolley in semi (as they do with worn COL's)

Now it seems like a rewire from removing a duff mosfet has caused a small evil spirit to enter the gun

Or a SHORT demon in there - ok I'll get my coat

(maybe he has a G&P Satan or Devil jet motor - OK I've got me coat on now)

GP-OTH021-1L.jpg


GA-GP170MTRL-lg.jpg


 
Last edited by a moderator:
It's a golden eagle high power motor. 

Right I will strip it back to nothing check all the wiring and let you know how I get on.

Cheers for the help so far 

 
Right with the motor plugged in but not in the gearbox and attached to the battery just to see if is shorted, nothing. The motor only span when the trigger contacts were pushed together. 

View attachment 27092

 
Close the gearbox up with Trigger etc but leave spring out

The trigger could be pinched or wires squished in the box

 
Sitting Duck said:
Close the gearbox up with Trigger etc but leave spring out

The trigger could be pinched or wires squished in the box
Click to expand...
Click to shrink...


Yeah that's what I was thinking maybe the trigger didn't sit probably when I closed the gearbox and pushed the contacts together or maybe it was shorting on the box itself. 

I'm actually waiting on some grease in the post before I can resemble the gearbox again.

 
The red wire's insulation at motor looks a tiny tiny bit chewed but nowt to worry about.

The red wire is dead completely dead even if it shorts on motor plate (or should be)

so the short has to be happening with silver & red wires somewhere at switch or leading up to it.

This short is being stopped on safe due to the prongs not completing the circuit

but goes nutz once the copper selector plate tab makes contact in semi/auto

If a short took place at around the bevel leading up to switch the gun would fire in safe

somehow a bit of solder or something is touching crap it shouldn't

Them copper tabs run around the side/back of switch to finish at prongs to be bridged

HY118.jpg


There two main types of switches - no tabs and with tabs needing copper plate selector

(actually there is a third type/variation rare switch with prongs but with a link in them)

32538-5.jpg


Somewhere at that switch area a short is taking place,

maybe a blob of solder is shorting out when the trigger gets squished slightly closed up

but short doesn't flow to motor due to prongs being open in safety

 
Last edited by a moderator:
Yea I reckon your right it's around the switch somewhere. 

Oh quick question when I fix it my mate wants it's locked to semi. What's the best way to do this?

 
uniweekendwarrior said:
Oh quick question when I fix it my mate wants it's locked to semi. What's the best way to do this?
Click to expand...
Click to shrink...


Your mate will love this - with a mosfet - lol

1 - a programmable one can be set to only fire a single shot burst on full auto instead of 3, 5 round burst etc...

2 - a regular mosfet but with an additional switch and fully locked to semi by selector plate mod

The extra switch if/when the gun locks up - you not got auto so a hidden switch can be pressed to full auto/clear it

3 - a screw stopping fire selector enabling auto - but pita if it locks up, but can be removed I guess

4 - possible plug in burst wizard like avacado but unsure if 1 rnd burst would work 101%

kong burst wizard might do it in plug/play mode perhaps and is a mosfet if needed to hardwire it in at some point

think best way for a SR25 is a selector plate mod, diy 3034 with extra switch etc...  as that is what it is meant to be

 
Last edited by a moderator:
Last edited by a moderator:
uniweekendwarrior said:
what about the selector plate mod?
Click to expand...
Click to shrink...


6-Mark-Plate.jpg


Careful you lose Auto for good until you buy a new selector plate

http://www.airsoftsociety.com/threads/how-to-semi-lock.132570/

Pico mosfet is perhaps easier or Nano than making just one DIY one up

(but then you will need a soldering iron anyway - so what is a bit more soldering to build your own)

http://www.patrolbase.co.uk/airsoft/gate-picossr-3-aeg-micro-mosfet-unit.htm#.Wdu4uVtSzIU

or

http://www.patrolbase.co.uk/airsoft/gate-nanoasr-3rd-gen-advanced-solid-state-relay-mosfet.htm#.Wdu4aVtSzIU

When the old mosfet blew - ^ these ^ are what the owner should have replaced it with

the extra switch - a cheap tiny tactile switch with wires hidden/glued inside a fixed m4 DMR stock

switch-pigtail.jpg


just basically a way of making it cycle on auto if it ever got stuck

return to dead zone/safe zone simply pop mag, click extra trigger inside stock/magwell if feeling clever

gun cycles on auto clearing lockup without needing to strip or try to pick AR latch etc....

TBH - f*ck knows why when companies make a DMR type gun they don't f*cking do this anyway

 
Last edited by a moderator:
You must log in or register to reply here.
Back
Top