Tuning my modding/tunning error - MK2 air leaked out completely

[bigHUN]

This winter was loooong at my place, I didn't visited my range for a while, but I was tuning the .25 Impact MK2 in my garage only.

Last change was a replacing the HS, also the Impact power wheel to Crown MK2 - back about a month ago, but didn't tested yet until now. Free time today, let me check first with 41gr slugs in mind to re-tune for 44gr and prepare for the season. Lowered the Reg to 125 and reading 950 fps, OK this shall be a good start....

Tent shot and a big hisss, the gun lost the entire air within two minutes, air leaking out from both holes, the 2mm oring but also from transfer port.

First came to mind, I let the VS adjuster all the way out and the increased HS knocked the valve rod way too far and the 2mm oring suffered.

But that would leak the valve rod only, looks like I busted the peek puppet as well? {btw, my machinist reworked that puppet to a smaller OD back in Jan}

 

[bigHUN]

Without taking things apart (I don't have time for that next couple days) I am just tinkering about my steps:

- a stronger HS, minimum or no VS;

- a lower Reg;

- and the replaced Power Wheel...

All these changes won't allow fully closing the Valve? even for a hair?

Never compared/measured the spine between the two PW's, could that be the new power incline is more aggressive vs stock MK2?

As we can see from the pic, yes the PW is on Max but the slider still has some free room to adjust, maybe about 1mm...

 

[dizzums]

dont feel bad, the first time i broke down my blitz to attempt some trigger work i punched the trigger assmbly pins and yanked it out .. the gun went full auto instantly for the entire tank .. it was quite intense, i needed to change my shorts not kiddin lol ... later i did manage a better trigger though ..

 

[bigHUN]

I just tightened the VS knob back to forth line and power up the MK2 again, interestingly it holds the air.

I did couple dry fire shots into a pillow (in my basement men's cave) still holds the air. I will leave it overnight and try to tune tomorrow again.

Looks like with a VS all the way out there was no counter-pressure on valve puppet to close against the Reg 125. For now this my cheap theory....

 

[ImpactX]

Seem like damage o rings or something stuck inside preventing the rod to seat completely. There end of the rod should sit flush. In your picture it doesn't seem to be flush. So it doesnt completely seal. Like it or not, you will have to tear it down and inspect the o rings inside.

 

[bigHUN]

...There end of the rod should sit flush. In your picture it doesn't seem to be flush. So it doesnt completely seal....

That is correct for the stock guns only, but once you change the valve puppet that distance/dimension can be just anything, and honestly who cares any longer. The same applies to C1 and B8/10.

I have reworked the peek puppet 2x already...that OD drives how far the valve rod sits in relation to ie back face in the rear block .....part of a power-mod.

 

[Vetmx]

Yeah, the hammer wheel influences the valve rod. That’s why you back the wheel down to minimum when you set the C1. That other wheel must be more aggressive.