Yes Mr. Barreira, I am glad to help you find the air leak in your FX Streamline, but I will answer your private question publicly on the forum so others my benefit from the information. There is no charge but please make sure you give me one green ball for helping you...sorry that's a joke.
Ok, first let me say there are only a couple places on a Streamline where you can get an air leak, and these can be checked very easily by putting a little soapy water on to see if there are any bubbles. However, there is one place where the possible leak is not so easy to detect, which is at the valve pin.
Lets eliminate the easy ones first by putting some soapy water on them... check where the
air gauge screws into the front end cap on the air tube (G12 5003 Plastic Bushing 4mm) ; next check where the
front end cap screws into the air tube (G9 19485 O-ring 23,0x2,5 NBR 70 and G10 & G11 19484 O-ring 24,0x2,4 NBR 70); next check where the air tube screws onto the
rear end cap that is attached to the breech block (B5 19485 O-ring 23x2,5 NBR 70). Assuming you have no leaks at any of those three places lets check the vent hole in the side of the air tube towards the rear.
If any of those first three places are blowing bubbles you can eliminate the leak by installing a new o-ring of the proper size. These are listed on the FX Streamline parts diagram. If your vent hole in the side of the air tube is blowing bubbles then you replace both of the o-rings on the outside of the regulator sleeve (G2 19514 Distance Regulator).
http://www.fxairguns.com/wp-content/uploads/2016/12/Streamline-Exploded-drawing-pdf.pdf This brings us the last place you can have an air leak on your Streamline... the
valve pin. There is a little itty bitty teeny tiny o-ring on the front of the valve pin that needs to be replaced from time to time from wear, but they break sometimes and can cause an air leak. They are not even listed on the parts diagram, but I will give you the correct information so you can order some from FXUSA. These little o-rings are Item #2528 - 1.5mm x 1 NBR70 - $.77 each + shipping.
Here is how to remove the valve pin to check the little o-ring on the front of it: Let the air out of the gun by unscrewing the air gauge 1/2 turn or so using a very thin 11mm open end wrench (you may have to grind one down). Next, unscrew the air tube and remove it and lay it aside. Next look down inside the breech block where you took off the air tube and you will see a little silver disk with holes all around it and an Allen hole in the center...use a 3mm Allen wrench (if I remember correctly) to remove the silver disk. Then using a stout pair of needle nose pliers pull the valve pin out. Replace the little o-ring and reinstall the valve pin by placing it in the hole you removed it from. You will have to put quite a bit of pressure on it to get it to pop in and seat down all the way. I recommend you use a tiny drop of silicone oil or grease on the little o-ring to help it slip in. It is a tight fit! The easiest way I have found to seat it is to get it started in the hole and then using something like a hinge pin or drift punch and a ball peen hammer I give it a good tap to seat it...and that is how I do it.
Then simply put your gun back together the way you took it apart. The one last o-ring I would replace while your at it is the breech o-ring. This should keep you busy for awhile...let me know how it goes. My last advice? Take your time and be patient with yourself...this is all very easy so don't turn it into something hard. If all else fails I will let you ship me the gun and I will fix it for you. And don't forget my green balls!
All the best, Chuck
