FX FX Crown, Can't find leak

[thumper]

10 bar in a WEEK? I don't know that id even be fooling with it. That's an insanely small amount of air loss, so little that I wouldn't even trust a gauge to be accurate enough to see it and even then a temperature change would cause more pressure difference.

Dunk the whole action in water if you ever hope to find something this small.

Just shoot it if it's working well.

 

[Joedirt199]

May just have to pull the barrel off and dunk the reciever and bottle together in a tub of water to find the very small leak. Then give it a thurough drying.

 

[sobdiver]

10 bar in a WEEK? I don't know that id even be fooling with it. That's an insanely small amount of air loss, so little that I wouldn't even trust a gauge to be accurate enough to see it and even then a temperature change would cause more pressure difference.

Dunk the whole action in water if you ever hope to find something this small.

Just shoot it if it's working well.

Recently I didn't shoot the gun for 2 weeks and it lost almost 30 Bar. I'd check on it every day or two and watched the needle slowely but surely go down down down. This is with a 580cc bottle, so a smaller bottle would be even more. I can try not to worry about it and keep shooting, but it's very annoying, especially for a high end gun. I have four other PCP's that I can let sit for months withough losing any air. I'd be a little nervous about dunking the whole action as it seems water would get in places it shouldn't be and hard to dry out, but am open to more feedback on this.

 

[Bigragu]

May just have to pull the barrel off and dunk the reciever and bottle together in a tub of water to find the very small leak. Then give it a thurough drying.

You will need to do more than just give it a thorough drying. All the lubes will be tainted. I never recommend dunking the entire gun(minus stock and barrel) to anyone without first letting them know that if they go that route, to be okay with a full disassembly to not only dry out the innards but to remove and reapply fresh lubes where needed. Rust will come on fast, too. Hopefully your rig has had a stainless conversion on the fasteners.

Corrosion from moisture inside a regulator cavity will end up being a forever, unfixable leak just as bad as scratching an o ring groove, so be prepared to also pull the reg out and thoroughly drying the regulator cavities, should you choose to dunk the gun

 

[Scotty1]

You will need to do more than just give it a thorough drying. All the lubes will be tainted. I never recommend dunking the entire gun(minus stock and barrel) to anyone without first letting them know that if they go that route, to be okay with a full disassembly to not only dry out the innards but to remove and reapply fresh lubes where needed. Rust will come on fast, too. Hopefully your rig has had a stainless conversion on the fasteners.

Corrosion from moisture inside a regulator cavity will end up being a forever, unfixable leak just as bad as scratching an o ring groove, so be prepared to also pull the reg out and thoroughly drying the regulator cavities, should you choose to dunk the gun

You dunk the action, you rebuild the gun.

 

[sobdiver]

Update - THE LEAK HAS BEEN FOUND!!! This is not a test. THE LEAK HAS BEEN FOUND!!! LOL.

I contacted Utah Air. Said I wanted to try and fix the leak on my own and explaned all the places I checked. They suggested checking the back of the gauges with the leak detector as well as removing the barrel and checking the transfer port with leak detector, which might have greater accuracy than the balloon test. After removing the barrel and letting a little solution run down the transfer port hole the leak detector started foaming up like crazy. Here's the view from the where barrel was removed:

Here's the view from the other side after pulling back the pellet probe:

After this successful test I cleaned out as much leak detector as I could with a paper towel. Then I put the barrel back on and fired a bunch of shots to blow out any remaining moisture. I then degassed the gun and removed the power adjuster, the one marked "Low Medium High" (some guns this adjuster has the caliber instead) to inspect for moisture. Everything nice and dry. Next time not sure why to not add leak detector at the white arrow instead. I believe this is still a safe item to remove while the gun is pressurized:

So, what I learned is to not trust the balloon test for a valve leak. The valve can leak and the air can escape without inflating the balloon. I'm going to try and replace the valve stem and valve seat for a fix. UA will send to me under warranty.

 

[NAProf]

Hi,
Just a quick note. Getting the valve seat out without the little special tool is a pain. Look at 910Airguns or Bagnal and Kirkwood to buy the tool. There is a nearly identical tool for the Panthera/Dynamic/King but it is too large to work on the Crown. So get the Crown specific one. If tou can't find it let me know and we can see about loaning you mine.
Cheers,
Greg

 

[orangeokie]

Here is the story and resolution of a leak on my brand new Crown Mk2 Continuum, right out of the box.

FX Crown Air Bottle question

My new Crown is leaking around the air bottle, right out of the box. Can someone verify if there is supposed to be a rubber washer in there somewhere, either in the rifle part or inside the bottle neck? Thought I would check here before calling FX for help.

www.airgunnation.com

 

[sobdiver]

Hi,
Just a quick note. Getting the valve seat out without the little special tool is a pain. Look at 910Airguns or Bagnal and Kirkwood to buy the tool. There is a nearly identical tool for the Panthera/Dynamic/King but it is too large to work on the Crown. So get the Crown specific one. If tou can't find it let me know and we can see about loaning you mine.
Cheers,
Greg

Thanks for the offer, appreciated. To get the valve seat out you can use hemostats. To reinstall the valve seat a special tool helps. Here's a couple of videos that show both removal and installation:

(removal 7:50, reinstallation 45:45)
I've seen the FX Valve installation tool at Capefearairguns, UtahAir, as well as Ebay. I bought one on Ebay called "FX airgun valve seat tool" I also have Hemostats for when I'm ready to do the repair

 

[sobdiver]

The leak has been fixed. I received a replacemant valve seat and valve pin under warranty from UA. Replaced both and no more leak. I was unable to remove the old valve seat with unmodified hemostats. So, I modified a pair like in this picture, to make removal easier. Even so I struggled for a bit, but did succeed.:

I used the tool to install the new valve seat:

I purchased a backup valve seat and valve pin to have on hand in my parts kit. I could have sent the action in under warranty to be repaired, but it can be enjoyable working on the gun and getting comfortable with the process. After the repair I tested with leak detecter by removing the side power adjuster. No bubbles and now the gun has been sitting for two days with no signs of any leaks. A side note, If you are monitoring a gun for a slow leak it can be helpful to tap on the gauge when checking. Previously it sometimes looked like my gun hadn't lost air in the last day, then as soon as I tapped the gauge the needle would move down a little. Good to tap the gauge also when checking for creep.