• The AGN App is ready! Search "Airgun Nation" in your App store. To compliment this new tech we've assigned the "Threads" Feed & "Dark" Mode. To revert back click HERE.

FX Impact M3 Front Regulator Rebuild

I have a small leak (<10bar/day) on the first regulator on my impact m3. After doing some bubble tests I found that its coming from the small hole in the side of the reg. I have replaced the piston and set screw o-rings but it’s still leaking.
I am having trouble identifying which o-ring goes on this brass piece;
3B226BF5-4C42-40D0-B135-7C80CA2AA0DC.jpeg


Have been considering moving over to the Huma-Air regulator and this might be a good excuse. Anyone have any experience with their front reg?
 
First of all let’s talk about how you removed 1st reg did you use 23 mm socket and did it come off easy.
I didn’t have any 23mm sockets on hand so I used one of my grandfathers old monkey wrenches and a cloth. I removed the barrel, rail, valve adjuster, etc and put the gun in a vice between two pieces of rubber.
It did not come out easily.
 
  • Like
Reactions: Kamanthi-
Hi Tmjvb!
There are three Orings that keep the high-pressure air out of the section of the regulator that has to "breath." Look at the M3 schematic, section X2. It shows all the parts of the Amp2 regulator. Note Orings identified as X2-5, X2-7, and X2-8. The first two are both 4 x 1.5 NBR 70 rings. One is on the piston, and one is in the piston side of the regulator body. The third is the Oring inside the rifle body just beyond the threaded section.
The problems that I have seen with this kind of leak is that in getting out the Oring in the rifle body it is possible to scratch the seating surface enough to allow a small leak. I am including a cutaway from a CAD drawing I did of the Amp 2 regulator. The top three Orings are what is keeping the air out of the area with the Bellville Washers.
Cheers,
Greg
Cutaway Amp 2.jpg
 
  • Like
Reactions: radjabatak
Hi Tmjvb!
There are three Orings that keep the high-pressure air out of the section of the regulator that has to "breath." Look at the M3 schematic, section X2. It shows all the parts of the Amp2 regulator. Note Orings identified as X2-5, X2-7, and X2-8. The first two are both 4 x 1.5 NBR 70 rings. One is on the piston, and one is in the piston side of the regulator body. The third is the Oring inside the rifle body just beyond the threaded section.
The problems that I have seen with this kind of leak is that in getting out the Oring in the rifle body it is possible to scratch the seating surface enough to allow a small leak. I am including a cutaway from a CAD drawing I did of the Amp 2 regulator. The top three Orings are what is keeping the air out of the area with the Bellville Washers.
Cheers,
Greg
View attachment 396031
Thanks
This is regarding the first stage regulator. I was having trouble finding the o-ring for the brass piece that seats the delrin piston.