[Solved] Mag leaking like a colander - am I on the right track to fix it?

[ideinit]

My mag setup:
- lv 10 (no shims)
- x-valve
- ULT
- classic rail

Recently when I re-ran the air supply for my mag, from ASA -> valve directly, to ASA -> foregrip -> valve, my mag started leaking down the barrel, and out the back. Re-running the air supply probably have nothing to do with the leak, but it's just the last thing I did before it broke.

After browsing the the tech forums I think I have to do the following:
- replace regular piston (for leak out the back)
- down size lv 10 carrier (for barrel leak)

Also, my mag have always had a leak when the trigger is held, but not when it's released. What par of the ULT do I need to inspect/replace?


The parts are still in shipment, so it'll be a bit before I can test it out, but any suggestions welcomed.


EDIT: Should I just go ahead and replace all o-rings in the valve? I haven't done so in about 6 years...

EDIT: Added x-valve diagram so we can use part # to facilitate discussion



EDIT: added "no shims" as there were many mentions of removing shims

EDIT (03/01): I have done the following:
- completely disassembled the XValve and cleaned all parts
- repack the grease on the spring pack (#23&24)
- replaced reg seat o-rings (#7 & #20), reg piston o-ring (#21), carrier o-ring (#7) because the last one had a cut on it

Now it seems the back valve leak had temporary gone away, but it comes back every now and then if I tweak the velocity setting (regardless of the direction). Also I am still having a barrel leak. So I guess it's time to tune my LV 10.

EDIT (03/01): The initial problem has been fixed by comment #12. But a trigger problem had developed... will start another thread for that specific issue.

[Nobody]

Did you throw some oil in it?

[ideinit]

Did you throw some oil in it?

The golden rule of mag repair - it was the first thing I did

[Nobody]

Change the powertube oring first, then play with the L10.

[athomas]

Theory of orings says you should replace them if they are 6 years old, but in reality they are probably fine unless they are worn or dirty.

It is probably just coincidence that is started leaking after you changed the air lines. The only other thing that may have directly contributed, is if you used teflon tape and a tiny strand or two got into the valve, or if some of the old sealer from around the fittings got into the valve when it was dislodged when you changed the fittings. A good cleaning of the valve will do it good and allow you to check the condition of the orings.

You have an X-valve so the regulator piston assembly is the high pressure version. The piston assemblies don't usually go bad, so I doubt that is a problem. A leak out the back is probably just a piece of dirt in the regulator seat oring or a piece of dirt in the oring surrounding the regulator piston assembly. A good check is to reduce the velocity setting. If your piston assembly is worn out, the leak out the back will go away. If it doesn't go away, then the leak is due to a bad or dirty oring.

Holding the trigger should cause any leak out the front to stop. However, if you have too many shims installed in your powertube it could persist as a slight hiss for quite a while.

You should probably tune your level 10, since your mag has sat for a while. The orings might have swelled or changed dimensions slightly, which would affect its operation.

[ideinit]

Change the powertube oring first, then play with the L10.

Is that part #4, "Power tube tip o-ring" the diagram in the OP?

[Nobody]

Yes #4

[ideinit]

Thanks for your suggestions athomas, I will try them out tonight and get back to you.

[athomas]

Is that part #4, "Power tube tip o-ring" the diagram in the OP?

This oring doesn't do anything except keep the powertube tip from vibrating loose. It is not a sealing oring, so as long as its there, it is good to go.

The only oring in the powertube that might need changing is the powertube oring inside the carrier. It is number 7 on the diagram. I would try removing the shims and tuning the level 10 with what you have before I changed the oring, though. Your original one that is installed is already broken in, so you don't want to change it if you don't have to.

[ideinit]

This oring doesn't do anything except keep the powertube tip from vibrating loose. It is not a sealing oring, so as long as its there, it is good to go.

The only oring in the powertube that might need changing is the powertube oring inside the carrier. It is number 7 on the diagram. I would try removing the shims and tuning the level 10 with what you have before I changed the oring, though. Your original one that is installed is already broken in, so you don't want to change it if you don't have to.

I have no shims in my LV 10. (I have updated my OP with the info).

I figure I will try to stop the back leak first before working on the bolt, but thanks for the info on the broken in o-ring.

[ideinit]

[...]You have an X-valve so the regulator piston assembly is the high pressure version. The piston assemblies don't usually go bad, so I doubt that is a problem. A leak out the back is probably just a piece of dirt in the regulator seat oring or a piece of dirt in the oring surrounding the regulator piston assembly. A good check is to reduce the velocity setting. If your piston assembly is worn out, the leak out the back will go away. If it doesn't go away, then the leak is due to a bad or dirty oring.

[...] You should probably tune your level 10, since your mag has sat for a while. The orings might have swelled or changed dimensions slightly, which would affect its operation.

Thanks for you pointers, I have sort of fixed the leak... please see the following (which I've also added in the OP)

EDIT (03/01): I have done the following:
- completely disassembled the XValve and cleaned all parts
- repack the grease on the spring pack (#23&24)
- replaced reg seat o-rings (#7 & #20), reg piston o-ring (#21), carrier o-ring (#7) the last one had a cut on it

Now it seems the back valve leak had temporary gone away, but it comes back every now and then if I tweak the velocity setting (regardless of the direction). Also I am still having a barrel leak. So I guess it's time to tune my LV 10.

[athomas]

Once you change the level 10 carrier oring, you need to tune the level 10 bolt. The carriers adjust the tension of the oring, so if you change the oring you need to adjust the fit of the oring on the bolt stem using the different sized carriers.

Since the leak out the back comes and goes independently of the velocity adjustment direction, are you sure you have the back section completely cleaned.

[ideinit]

Once you change the level 10 carrier oring, you need to tune the level 10 bolt. The carriers adjust the tension of the oring, so if you change the oring you need to adjust the fit of the oring on the bolt stem using the different sized carriers.

I had managed to find an used, broken-in carrier o-ring and that had stopped the bolt leak with the current carrier (my smaller sized carrier hasn't arrive from AGD).

Since the leak out the back comes and goes independently of the velocity adjustment direction, are you sure you have the back section completely cleaned.

Initially I had taken the valve apart, wiped everything down with rubbing alcohol, repacked the lube and lubed all the o-rings by hand before installing.

I took the valve apart again but just lubed all the threads/o-rings/contacting-parts and reassemble. It's currently not leaking but I am not quite sure if it is shooting at the right FPS since I cannot chrono at home - but at least it's not leaking out the back.

But now the trigger is misbehaving - will start another thread regarding this. Thanks for your help, athomas!