P90 Mis-Feeding

[Double 0 Jedi]

I have a CA Sportline P90, feeding with this one is a huge issue. High Caps or mid caps makes no difference, firing is just as intermittent.
I think the problem is in the nozzle as when I look down the hop up feeding tube the nozzle A) does not always seem to return far enough to allow a bb into the hop up. B) does not sit in the same place when it has been fired. Some times the nozzle sits all the way forward some times it sits half way.
My inclination is that the Tappet plate is worn and therefore not returning correctly and pulling the nozzle back, but I have no idea about how why the nozzle will not sit forward sometimes after firing. Week Tappet return spring Perhaps ? Any help would be very much appreciated.

[Delta Cypher]

Re: P90 Mis-Feeding

Did you have the gun from new? has it always had this problem?

If anyones done some work on it they may have have put the wrong air nozzle in (I've seen it happen a few times) which is litterally a mm too big and causes feed problems.

If not then yes your more than likely looking at the tappet plate, so check the tappet spring and sector gear engagement area of the tappet plate if this is worn it might not be pulling the tappet plate far enough back. You may also want to look at a gear delayer (a small clip that goes on the sector gear) to help the timing of the gearbox.

Hope this helps!

[richardy]

Re: P90 Mis-Feeding

check its the right air nozzle and tappet plate and that they are operating freely and correctly.

[Double 0 Jedi]

Re: P90 Mis-Feeding

Thanks for the help, still having issues. The gun is currently only firing on full auto, I can achieve semi auto by pulling the trigger slightly, however if I pull the trigger too slightly it just results in the motor whining but the gears not engaging with a full cycle. Now this could be the cut off lever as I have read that when these are worn they stop working and that does seem to be the case here, although I can’t find any information as to which end wears, is it the end where it contacts the gears or the trigger contact end, any one ?
I have fitted a mosfet but it does not have active breaking, I am not sure if the semi auto thing is a contact issue or a cutoff lever issue, can anyone explain exactly how the p90 cut off lever works, by that I mean exactly how it works, which part engages with which gear ? What happens with the trigger contact.

[richardy]

Re: P90 Mis-Feeding

i believe the p90 from memory as a bar on the trigger , you pull the trigger it moves the bar a predetermined amount. all the way should fire full auto, a little should put it in position to be knocked by the cut off lever... I think the cut off lever on the p90 is always on, promethues do a nice one for 20 quid.

When you select singel on the selector, it should only allow you to move the bar X amount if on single you can still move it far enough to go into full mode, then maybe you need to look closer at the selector switch near the trigger and make sure it properly restricts its travel, and then if thats fine, make sure the position of the gearbox is correct, i know it sounds strange but everything in a gear box is designed by measurements, so if the selector in singel is only allowed to move 10mm, if the gearbox is 9mm away, your moving 1mm into full auto territory, i mean the numbers are fictional but you get the idea..

The cut off lever is a see saw lever, one side rests agasint the sector gear, a lobe comes round on the sector gear and cuases the lever to raise, causing the other end of the lever to raise, this lifts the trigger block enough to disconnect and return to its original starting position, like a reset.

[Double 0 Jedi]

Re: P90 Mis-Feeding

ok sorry to resurect an old thread but it is my thread and I have an additional question. Having given up completely on hi-caps for My P90 I am using MAG 170 round mid caps and a recently purchased low cap. the low cap feeds fine, but the Mag mid caps are double feeding, fires every time but always two bb's. Searched tinternet and found someone else had a similar problem, but no clue haw to rectify the problem. Has anyone here had any double feeding issues with MAG P90 midcaps ?