Cyma M14 EBR gearbox jamming - help needed

[SCAR_Jester]

Hi all,

Got my Cyma M14 and for a while it worked very well, have not opened it up past taking the barrel out to put in a new hop bucking.

Suddenly when firing it jams and all I hear is *click*

I took out the gearbox and the motor was trying to turn but couldn't.

I checked all solder point and even if the motor was going the right way with 3 different fully charged 8.4v NimH's.

I tried moving the gears by hand and it wouldn't budge, opened it up and it turns perfectly. I am completely baffled by this and have no idea what is causing it as all possibilities I know off have been checked off.

 

It should also be noted that the cutoff lever for changing between semi and full-auto will happily go to full-auto position but only when the gears are in the correct rotation position will it go to semi-auto.

 

After opening the box for a 3rd time and closed it up, it fired one shot on semi, I then put it on full auto and it just went *click*

 

If anyone has a fix or could help with this that would be great.

 

Thanks

- Corky

 

[AK47frizzle]

Of course the gears won't budge, they are under tension by a strong spring.

 

The only thing I can think of is the trigger contacts are slipping out of place or the selector plate is iffy. I've had this before with my AK a few times, had to realign some parts regarding the trigger and now works fine. Check the internals of the gun itself too, maybe something had broken off and is catching on the gearbox.

[SCAR_Jester]

Of course the gears won't budge, they are under tension by a strong spring.

 

The only thing I can think of is the trigger contacts are slipping out of place or the selector plate is iffy. I've had this before with my AK a few times, had to realign some parts regarding the trigger and now works fine. Check the internals of the gun itself too, maybe something had broken off and is catching on the gearbox.

Tried looking inside already, oddly enough when it was stuck the sector gear was not near the piston to stop it from moving when pushed by hand.

Don't know how trigger contacts would be a problem, I mean the motor actually gets power, you can feel it try and move slightly as well as the battery heats up fast so contacts are fine.

[TheGrover]

The anti reversal latch has given me bother in the past. Could try that.

[SCAR_Jester]

The anti reversal latch has given me bother in the past. Could try that.

What should I do with it?

[TheGrover]

What should I do with it?

Check that it seats correctly in the box shell, that its the right way round, the spring engages it correctly and there are no signs of damage on the latch or the gear

[SCAR_Jester]

Check that it seats correctly in the box shell, that its the right way round, the spring engages it correctly and there are no signs of damage on the latch or the gear

Righto, will do. I'll reply later tonight when I'm free and able to open it up

[SCAR_Jester]

Ok, fixed the blasted thing. Originally the piston was stuck in the gears and after I fixed that problem I placed the cutoff lever in

Top tip fro any M14 owners, the cutoff lever has to go in at specific turns on the sector gear as it can get caught on a part if it goes in at the wrong rotation (at least mine did)

So yes, fixed.