Xyl arp9 MOSFET removal and replace with trigger block mod

So basically the mods we have done are not going to end well for the stock MOSFET circuit, so have installed a SHS trigger block.
The problem is after trying a stock trigger and a speed trigger it almost works but it’s like the trigger is slipping off the trolley and power is cutting out after one shot.

Has anyone performed such a mod successfully and what trigger did you use?

Also it will have an easyfet but for now just want to get the trigger working in the traditional sense.

Check your cut off lever and spring is not worn or too loose. Is it a new block? Trolley/spring not worn?
Also, check for sideways movement on the trigger itself. Some are bad as the holes for them differ in size, and the triggers themselves I’ve found can be like a mil different in depth or post diameter…
Triggers can be shimmed with normal shims.
I put a Perun optical in my arp gearbox no problems, so regular trigger block should be fine.

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Ive had this problem. You need to glue something under the trolley where the trigger pushes it, so it doesnt slip underneath.

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Ok thanks for the suggestions. Now at the point where the trigger works. But only fires in semi and keeps sticking back sometimes.
Have been chasing tail heaps on it.
4 different triggers tried
Certainly is and of beast.
It fires one shot even in auto then cuts off.

Not sure if this helps, but check the alignment of the chip on the selector switch in the lower receiver

I havent had this issue with the Arp9, but in one of the first cymas i built, I managed to bump the chip as i was installing the box

Displayed almost the same issue, auto was semi and semi fired but felt like the trigger was catching


Check the wiring running under the trigger; can bulge up a bit and put pressure on underside, and the trigger spring itself…some can be very soft.
Also your safety lever can be too tight…might not be fully travelling, and interfering…
Edit I had similar issues with a Well box ages ago. When you set your gears when rebuilding, make sure the cut off cam on the sector is not engaging the cut off lever even a little bit. This will lift the trolley a touch and put it out of whack with the cycle. Not sure if this is a thing, but was the ONLY problem I had at the time, and the problem went away after I allowed for it.

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