P90 Non-firing issue, help!

[Deej]

Hey guys, wondering if anyone here can help me.

I have a damn-near-stock Asia Electric P90 which isn't firing. At first I thought it was a jamming issue being caused by a dirty hop bucking, but after breaking down the barrel group and cleaning every piece, it still hasn't helped.

I haven't adjusted the gearbox myself, but it supposedly has a replacement Lonex nozzle, as well as a replacement stock hop assembly.

To clarify, the gearbox appears to operate as it should: when the trigger is depressed the weapon cycles, and the nozzle is shot forward as it should be. However whereas that would normally cause the round to be ejected, the BB just sits there. It also seems to be unseating, like when the nozzle rocks forward it tips the round out of the cradle and millimetres toward the bucking nub, though that doesn't always happen.

So I thought it could be a gearbox issue, like the burst of air isn't being delivered? Well, if dry-fired I can feel the air exiting the muzzle, which makes me think it's compressing okay.

It may be worth noting that the captive round seems to get dirty when the weapon cycles. It sits still but is slightly rotated by the air passing it, and dark marks are applied to the BBs surface, seemingly in relation to the weapon's firing.

So does anyone have any conjecture or - even better - experience on this fault? Could it be that the gearbox isn't sitting right in the body, or is the gearbox an only-fits-this-way part in P90s? Could it be the nozzle (it looks a little beat-up around the tip..)?

 

[Spatch]

Nothing should be getting dirty in there, it sounds like you have a particularly poor air seal, I would personally be changing the air nozzle for the one part, especially if it's damaged, air seal is everything, better the seal, better the rifle, as to where the dirt is coming from, short of taking the gearbox down and checking for filth in the cylinder and head, I doubt you will know

 

[Deej]

Mmkay, so you reckon it's the nozzle's fault?

How invasive is a nozzle replacement? I've never touched my gearbox out of a fear akin to a medieval villager's fear of magick, I just do not feel confident about my ability to get in and out of that assembly without screwing something up.

Do you know if it is possible to incorrectly seat a P90 gearbox within the lower receiver? I'm just concerned that maybe even after I replace it I'm just going to stick the 'box back in and wreck the new nozzle right away thanks to an incorrect firing angle..

 

[sunstar]

Sounds like somethings realy wrong inside the gearox if it sparys dirt on the bb!

I would take it out, open it, clean and check everyting! And check the lenght of the nozzle....

Inserting a box in a p90, is not that hard... So if you did not force it in place then i gues it should be sitting correctly ...

 

[jcheeseright]

the gearbox only goes in one way, sounds like you've got some seriously bad things happening inside the gearbox if it's spraying dirt (probably grease) onto the BB, there's a number of potential causes but I'd go first with it probably being your piston/piston head that's bought it. the grease being sprayed out of the nozzle indicates that the piston head o-ring isn't working correctly.

If in doubt, take it down to lock and load and ask if LT can have a look at it.

 

[Deej]

Yeah I didn't force the mechbox back in or anything, it's just that I don't see how anything could've done such a number on the nozzle tip unless it was colliding with the hop unit in some way..

I'll get it looked at I guess. This thing has been endless trouble since halloween :S