Hi all, new to this new to this air gun thing but have a blast, just installed a slug kit in an FX impact, M3, all went well or so I thought but when I screwed the bottle back on the second reg was hissing out air, screwing the centre one back in stops the leak but as soon as you back it out it hisses again. As I didn’t go near it have I done something else wrong? Or blown an O ring or something?
FX Impact M3 Second reg hiss
- Thread starter MrB7
- Start date
If you have the reg screw turned clockwise too far your under 80 bar and it hisses out the hole underneath the safety switch. Turn the second regulator screw out a half turn to get it to about the 80 bar low limit
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If that isn't the issue then you've probably blown the top o-ring on the regulator adjustment screw. Also an easy fix if you have a the tiny o-ring on hand. You can find the o-ring in a 6 pk on Ebay for around $6 delivered
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Hi
You didn't do anything wrong, when degassing a pcp if the o-rings have some time on them the chances are some of them will leak air and more likely on an impact because of the large number of o-rings. It is best to have an o-ring kit if you are going to degas your airgun.
Regards
Enkey
You didn't do anything wrong, when degassing a pcp if the o-rings have some time on them the chances are some of them will leak air and more likely on an impact because of the large number of o-rings. It is best to have an o-ring kit if you are going to degas your airgun.
Regards
Enkey
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Did you screw the center adjustment screw in while under pressure ? How much pressure is in your bottle and first reg.
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Two hour window. That’s what I give myself as a max time amount my impact is empty of all air. It’s been my experience, if in any task that is being done to my impacts take longer than two hours with the gun completely empty of air, I better plan on leaks as soon as I fill back up with air. Typically the regulator areas are the first to leak, and if not there, a leak will be then tied into the power plenum area. Ive been lucky the last couple of times as the o rings in these two areas were all replaced not too long ago, so when I went over two hours the leaks came from the gages, so I replaced the x rings on those. Easy fix.
These o rings are just taxed when doing their job in holding in high pressure air. They take on a whole new shape of their own by being stretched and pushed against one side in the groove they sit in. Some areas of the o ring get flattened. In the time the gun is empty of air, the o rings are now slowly falling into a relaxed state back in their grooves but because they’ve developed flat spots and have been stretched, the minute the gun is refilled with air the flat spot that used to be on an o rings side may now be on top, and that’s where the leaks come from. That’s just my theory on things.
Just yesterday I drained down one of my impacts to replace the rear block. I made sure I had everything ready at the bench, all parts, tools, and lubes. Had the block replaced and air’d back up within an hour and twenty minutes. No leaks
Lastly- going hog wild on silicone lube on o rings will cause leaks, also, especially on regulator o rings within an air tube. The excess lube will cause the o ring to push out of its groove and roll to the side. Just swapping out the o ring for new probably won’t fix it, either. You must first clean the air tube dry by removing all lube with acetone. Ive had to resort to lightly scuffing the area the regulator rests at with 1000 grit wet/dry sandpaper, wipe clean with acetone, and now the new o ring has an area to “grip” against and not roll off its groove.
These o rings are just taxed when doing their job in holding in high pressure air. They take on a whole new shape of their own by being stretched and pushed against one side in the groove they sit in. Some areas of the o ring get flattened. In the time the gun is empty of air, the o rings are now slowly falling into a relaxed state back in their grooves but because they’ve developed flat spots and have been stretched, the minute the gun is refilled with air the flat spot that used to be on an o rings side may now be on top, and that’s where the leaks come from. That’s just my theory on things.
Just yesterday I drained down one of my impacts to replace the rear block. I made sure I had everything ready at the bench, all parts, tools, and lubes. Had the block replaced and air’d back up within an hour and twenty minutes. No leaks
Lastly- going hog wild on silicone lube on o rings will cause leaks, also, especially on regulator o rings within an air tube. The excess lube will cause the o ring to push out of its groove and roll to the side. Just swapping out the o ring for new probably won’t fix it, either. You must first clean the air tube dry by removing all lube with acetone. Ive had to resort to lightly scuffing the area the regulator rests at with 1000 grit wet/dry sandpaper, wipe clean with acetone, and now the new o ring has an area to “grip” against and not roll off its groove.
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I may have headshot, didn’t realise that was such a bad thing till reading up here a bit more
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Thanks a lot bigragu, great tips to keep in mind, I’d better get me some spares just in case!
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Thanks all, screwed the 2nd reg screw in all the way, leak stopped, backed out half a turn, 2nd reg went up to 90 bar, leak continued, looks like I did an o ring. Screwed it back in to stop the leak so the gun can remain pressurised while I get a replacement. Thanks for the info all, pays to have some spares I think!!
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Tightening the regulator adjustment screw with the gun pressurized is not recommended because it will probably damage the regulator I would not recommend it, only experienced users who know the procedure to follow
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