Hatsan Gladius - tube leaking out fill port

[Underdog]

I just pumped up my Gladius .177 to Max pressure (@190 Bar), and now it's leaking out of the fill port. It's just a slight hiss, but that's just totally not acceptable.
I've pushed the fill probe in and out a couple of times, and fired a few rounds to let the pressure drop, but it's still leaking.
I've pulled the tube out and inspected it, but see nothing. **edit** actually I see a bit of white residue inside the fill port. Just a couple of specks of something.**edit**

What do I do now?

[Privateer]

I had the same problem with one of the AT44's.
I found it had a bit of a burr where the fill probe goes in.
It was shaving the o-ring a tiny bit every time I filled it and those shavings caused a tiny leak!
Plus I had to change the O-rings much to often on the probe!

I degassed and took everything down for a good cleaning and de-burred the fill port area with 600 grit sand paper.
That solved my problem.

[Underdog]

This is leaking with the fill probe removed....

[JTB530]

My BT-65 did the same thing. The o ring in the tube needed replaced. The original was very brittle. Not a hard task just need a good way to hold the tube tightly without scratching it so you can disassemble it.

[Privateer]

This is leaking with the fill probe removed....

So was mine!

[Finn]

I have had this problem with AT44 and there was multiple things wrong.

O rings in my gun were yellowish transparent ones and they had crumbled into pieces. I replaced them with metric size NBR 90 rings and it worked well for some time, then it started leaking again from fill port. The small hole inside the fill port had very sharp edges which had cut small rubber shavings off of probe o rings and they were stuffed in valve seat.

It seems that even with the hole edges rounded it only needs a spec of dust in the valve seat to make these things leak. Also some cheapo o rings dont immediately return to their original size when the pressure is released and if the probe is pulled out right away it may feel tighter than normal and another o ring is busted. I recommend a bit undersized highly elastic o rings on probe and maybe wait a little bit before pulling the probe out. I always give the pump few strong pumps to drive particles out of the probe before connecting it to the gun.

[Underdog]

Thanks guys, the tips are most welcome. I like the idea of pumping to drive out any errant particles from the fill probe.
Anyone have a good suggestion on capping the probe so it doesn't pickup stray particles of whatever?

And then my next question is how do you de-gas this tube?
And what do you grab the end of it with to remove the end?

[Finn]

Thanks guys, the tips are most welcome. I like the idea of pumping to drive out any errant particles from the fill probe.
Anyone have a good suggestion on capping the probe so it doesn't pickup stray particles of whatever?

And then my next question is how do you de-gas this tube?
And what do you grab the end of it with to remove the end?

I have used a piece of heat shrink tubing with the other end pinched flat, but really any small piece of snug fitting hose is enough to keep the dirt out.  Do you have that brass Hatsan degassing tool? If so then its simply a matter of turning a screw, if not I imagine that the leaking tube will de-gas itself anyway.

 I have the luxury of using lathe so thats what I used to hold the tank when turning the end with metal rod thru fill port. If I remember correctly, a 9mm (.354in) rod fits exactly but it is better to use a wee bit smaller and cushion it with tape or heat shrink. It needs to be quite a strong material so it does not bend and jam itself in the fill port. You can try using small oil filter wrenches with rubber or tape wrapped around the tube, but these tube ends tend to be quite tight. I had to actually hammer the rod to loosen the tank end, theres really no danger of damaging the port if rod is close fitting and smooth.

[Xraycer]

Anyone have a good suggestion on capping the probe so it doesn't pickup stray particles of whatever?

How about a small balloon?......kinda like a condom set-up.

On my Bullboss, I just leave the fill probe in full time, and just disconnect with the foster connection....no more damaged o-rings

[Underdog]

Not sure if I have the degassing tool or not. I'll have to check when I get home tonight. If it comes standard with a new gun then yes I should have it. I'll check my box-o-parts that came with. I seem to recall something like that...

So after degassing, you use a rod through the fill port to remove the end cap/pressure gage? I assume standard threads, not counterclockwise threads?

Thanks for the tips and help!

[Underdog]

Gotta love Youtube..
This looks like it would apply even if it's an AT44:

[Xraycer]

Not sure if I have the degassing tool or not. I'll have to check when I get home tonight. If it comes standard with a new gun then yes I should have it. I'll check my box-o-parts that came with. I seem to recall something like that...

My Bullboss came with the degassing attachment. I had no idea what it was for until I checked out that YT vid you'd posted....thanks!