Tuning Fx Impact Mk2 cheek rest air puff

[Glem.Chally]

Big thanks man. I ordered the Fx impact Oring kit and it should be here tomorrow. I installed the slug kit myself and made sure that the black ball is in the spring. I'm definitely going to replace the o rings in the power plenum and will report back when everything is put back together.

*** how do I prevent this happening again?

When I was tuning, I had the regulator set at 110 bar, hammer spring was 5 quarter turns from max and the valve knob was a little above the 4th line. Doesn't sound too crazy to me.

Maybe just "one of those things", I don't think it's overly common. It'll give you a chance to open up the gun and see how it works.

There's good videos on YT on disassembly and assembly which I'm sure you found.

 

[Bigragu]

I’ll tell you how it happened, it’s because you had your valve knob out to far. Just went thru all of this with a buddy of mine whose impact I worked on and while going thru “tuning by phone” we decided to start fresh and dial the valve knob out to line 4 and work our way inwards for the final tune to tighten up the ES and poof, the o ring at the valve stem let go. 

The rubber ball is to prevent valve rod over travel, but I believe with the added weight on the hammer weight four lines out combined with that lighter spring may be a tad too much. When all is back together I would start at 3 to 3.5 lines out on your valve knob, max.

This doesn’t happen on every impact that has the lighter valve spring/ball combo, as like mine for example. But I’ve seen it happen to 3 impacts, and your’s is the fourth.

 

[Tnp]

Ran into another issue. After replacing the o ring on the valve and the ones for the power plenum, I started piecing everything back together. Everything went well until I got to the install of the spring, hammer and hammerseat. The valve rod isn't going all th way back unless I push it back. This is how it sits now

There's a springy-ness to it and I'm now sure why

These are what's on the valve rod along with the upgrades from the power slug kit, am I missing anything?

 

[Tnp]

So I messed with the power wheel and it seems to have remedied the need to push in the springy valve rod. On power wheel setting 1 and 2. Power wheel setting 3, 4, and 5 requires force to push the valve rod in so that it seats properly visible via rear block. Is this an issue?

 

[Glem.Chally]

Sometimes you need to spin the valve rod a bit to get it to find home.

 

[Tnp]

I did. It's in proper alignment with the valve case in the rear block but there is spring tension and requires me to push on the valve rod while on power wheel setting 3, 4, 5 and max to get the valve where it needs to be. There is no tension and seats perfectly on power wheel setting 1 and 2.