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FX Impact M3, ”fart noise”?

Hey guys,

I have a two FX guns since a few years back and im very pleased with them. A Dreamline and a Impact M3.

Yesterday I ran in to a potential problem which I might need your help to solve. (Pardon my English but it’s not my native language, I’m from Sweden)

I was out in my backyard shooting 18 grain pellets and everything was working fine, suddenly I heard a not so loud “fart noise” from the valve/plenum area and when I shot, the pellet did not even hit the target due to loss of power.

I tried to shoot again 5-6 times, maybe a second after I cocked the gun this noise re-appeared and the gun lost its power before I even pulled the trigger.

I went inside to google the problem for a few minutes, dry fired it to see if I could feel any obvious leaks while shooting, but I couldn’t.

I refilled the gun and went out again, and now everything’s working as usual. I’ve shot about full 5 mags.

Have anyone of you a clue of what’s going on, could it be a o-ring in the valve area who’s about to break? Valve rod seal?

I’m planning on ordering some o-rings in advance in case of emergency. 😀

Thank you all for a great forum ❗
 
Any mods done to it? With a light valve adjuster spring and heavier hammer spring installed, I have had to make sure the valve adjuster is screwed in enough. If it wasn't, it would bleed air out the barrel. Being that you said it would shoot fine afterwards, it doesn't sound like an oring. I could be wrong, but when ever I have an oring issue, it just bleeds air all the time.
 
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I refilled the gun and went out again, and now everything’s working as usual. I’ve shot about full 5 mags.

Looking at this one comment I'd have to ask if maybe you shoot the tank pressure down too much? Possibly well below the reg setting in such a way that the forces on the valve was causing air to be released? Can't explain the whys, but could be the reason filling the tank back up resolved the issue.
 
Any mods done to it? With a light valve adjuster spring and heavier hammer spring installed, I have had to make sure the valve adjuster is screwed in enough. If it wasn't, it would bleed air out the barrel. Being that you said it would shoot fine afterwards, it doesn't sound like an oring. I could be wrong, but when ever I have an oring issue, it just bleeds air all the time.
No mods at all, I bought it Brand new about two years ago.
 
I refilled the gun and went out again, and now everything’s working as usual. I’ve shot about full 5 mags.

Looking at this one comment I'd have to ask if maybe you shoot the tank pressure down too much? Possibly well below the reg setting in such a way that the forces on the valve was causing air to be released? Can't explain the whys, but could be the reason filling the tank back up resolved the issue.
Thank you for your response, but reg 2 is set at ~73b and reg 1 is set at 150b. I never shoot the air below the pressure on reg 1. So I have a good margin. 🙏🏻
 
Just out of curiousity and maybe someone else would know, but how low can the 2nd reg be set on the M3? Is 73 bar too low and causing the valve not to seal shut? Just a though as that sounds really low. Also, I believe Fx recommends a 30 to 40 bar difference between the 1st and 2nd reg.
70-75b is totally ok, according to Fx tech department I can go even lower (60-65b) but with decreased consistency.

150b is the factory setting and I’ve always had it there, so I don’t have to change it when shooting heavier projectiles.

I have good ES and good SD anyway.
 
Sounds like to me was the projectile was to big and air went by breech oring may have double fed it causing the extra pressure or a tight slug
I've had it happen to me trying to shoot a double feed out and my o ring was still ok
But the strange thing is that the noise came before the shot went off, before I even pulled the trigger.

Must have been something with the valve..