Author Topic: ATI NOVA LIBERTY LEAKY POPPET and VALVE connection (Read 13545 times))

AVS Stephen · « **on:** April 05, 2019, 08:41:01 PM »

I just discovered that two of my three ATI Nova Liberty are leaking at the poppet but no where else. Undiluted dish soap at the muzzle revealed bubbles on two of my guns. Pulled one of the guns apart and it appears that the poppet is digging into the valve and not making a tight seal. Looks like the brass valve needs to be turned down just a small bit to raise the lip on the valve. I'm hoping this will stop the leak.

Has any other Nova Liberty owners found this problem and have you done anything? Any help would be greatly appreciated.

FuzzyGrub · « **Reply #1 on:** April 05, 2019, 09:13:48 PM »

Both of mine are still rock solid, no leaks.

Can you post a clear picture of the sealing surface of the poppet?

Is one of the leakers your 1st gun, that has had the most use so far?

nervoustrigger · « **Reply #2 on:** April 05, 2019, 09:29:05 PM »

That's not a ding on the raised lip at the 6 o'clock position?

Wheelman · « **Reply #3 on:** April 05, 2019, 09:30:28 PM »

Mine had a slow leak at the o-ring that seals the air tube to the regulator block.
I resolved it by flipping and re-lubing the o-ring, it's been leak free ever since.

Wheelman

darkcharisma · « **Reply #4 on:** April 05, 2019, 10:40:28 PM »

Time for a make over or major upgrade to the valve Stephen. counter sink it and add a new poppet! just get rid of the ring all together.

yes i have those marks too, its the soft seal getting beat thus the poppet shell hits the valve face.

2 solutions: turn and make a deeper ring or counter sink and make a new poppet to seal. since the old seal will be going out soon, i think the latter will be better choice

Bob Pratl · « **Reply #5 on:** April 06, 2019, 05:48:19 AM »

Quote from: thebanker4 on April 05, 2019, 08:41:01 PM

I just discovered that two of my three ATI Nova Liberty are leaking at the poppet but no where else. Undiluted dish soap at the muzzle revealed bubbles on two of my guns. Pulled one of the guns apart and it appears that the poppet is digging into the valve and not making a tight seal. Looks like the brass valve needs to be turned down just a small bit to raise the lip on the valve. I'm hoping this will stop the leak. Has any other Nova Liberty owners found this problem and have you done anything? Any help would be greatly appreciated.

Caution in using undulated dishwater detergent as it will discolor and remove the anodizing if left on too long. It is too caustic and it is better to use Gas Pipe Leak solution that can be found at any hardware store. I have one AG that now looks like S*** and is down to bare aluminum, in some areas, after using dish water detergent.

AVS Stephen · « **Reply #6 on:** April 06, 2019, 06:36:08 AM »

Quote from: Bob Pratl on April 06, 2019, 05:48:19 AM

Quote from: thebanker4 on April 05, 2019, 08:41:01 PM
I just discovered that two of my three ATI Nova Liberty are leaking at the poppet but no where else. Undiluted dish soap at the muzzle revealed bubbles on two of my guns. Pulled one of the guns apart and it appears that the poppet is digging into the valve and not making a tight seal. Looks like the brass valve needs to be turned down just a small bit to raise the lip on the valve. I'm hoping this will stop the leak. Has any other Nova Liberty owners found this problem and have you done anything? Any help would be greatly appreciated.

Caution in using undulated dishwater detergent as it will discolor and remove the anodizing if left on too long. It is too caustic and it is better to use Gas Pipe Leak solution that can be found at any hardware store. I have one AG that now looks like S*** and is down to bare aluminum, in some areas, after using dish water detergent.

Bob, yes I'm aware of that. I stripped and cleaned the entire gun after using the dish soap. Thank you!

AVS Stephen · « **Reply #7 on:** April 06, 2019, 06:42:52 AM »

Quote from: darkcharisma on April 05, 2019, 10:40:28 PM

Time for a make over or major upgrade to the valve Stephen. counter sink it and add a new poppet! just get rid of the ring all together.

yes i have those marks too, its the soft seal getting beat thus the poppet shell hits the valve face.

2 solutions: turn and make a deeper ring or counter sink and make a new poppet to seal. since the old seal will be going out soon, i think the latter will be better choice

Duy. Yes. My first gun is starting to show the same signs of a slow leak as well. I working with someone now to make three new poppets using delrin. He pulled apart the poppet and noticed the seal is made of a very soft material. He believes this could possibly be a weak point on this gun. Only time will tell. I suspect over time many of these guns will develop a slow leak at the poppet seat. Hope I'm wrong about this.

AVS Stephen · « **Reply #8 on:** April 06, 2019, 06:47:04 AM »

Quote from: nervoustrigger on April 05, 2019, 09:29:05 PM

That's not a ding on the raised lip at the 6 o'clock position?

Jason, good eye. I noticed that too but I believe the leak has more to do with the poppet material being over compressed. I will smooth the raised lip with some 1000 grit just in case. My other two valves look perfect and they are leaking as well. Also, I have shot about two thousand pellets ( I've gone through 6 tins of jsb heavies plus other tins of pellets) through each gun in an effort to see what high use will do. I think I have my answer. The poppet material get compressed to the point where the steel outer case of the poppet presses against the brass valve.

Wayne52 · « **Reply #9 on:** April 06, 2019, 08:51:18 AM »

Stephen I'll be heading for the woods soon this morning with my Liberty, I really am liking this gun so far, ya sure can't beat the deal that ATI had for the non warranty guns.

Wayne52 · « **Reply #10 on:** April 06, 2019, 09:20:22 AM »

I stand corrected, I just was getting ready to head for the woods, checked the Liberty and it's leaked down from about 3700psi to the yellow in 2 days, I packed up the old trusty Airmax Dominator and will be using that today

randy_68 · « **Reply #11 on:** April 06, 2019, 09:22:51 AM »

I've got one apart now that is leaking thru the reg adjuster. Went camping this weekend so I'll get to it tomorrow night. While I'm in there I might make up a poppet to have on hand as I'm thinking about buying one for myself. It sure would be nice to be able to get parts as these are pretty nice guns.

RDB · « **Reply #12 on:** April 06, 2019, 09:45:47 AM »

I wondered if this could become a problem. The poppet sealing material seems to be the same as the QB series rifles, which is pretty soft stuff. And with the reg pressures some of these rifles are running at, doesn't surprise me they are getting deformed. Probably a new poppet in my future also.

FuzzyGrub · « **Reply #13 on:** April 06, 2019, 09:54:29 AM »

Probably the same or same design in the Freedom. Given the higher non-reg’ed pressures, going to be more of an issue.

AVS Stephen · « **Reply #14 on:** April 06, 2019, 10:08:33 AM »

These are very good guns at this price point. This is the first real issue that seems to be wide spread. I will contact Tan Keat at Nova Vista and let them know the poppet material is not suitable for this gun and it's very high pressure.

Hopefully, this will be the only serious issue with this gun. So far, it appear to be a pretty tough design as I have beat these gun up pretty good. Aside from this poppet material issue no other big problems.

FuzzyGrub · « **Reply #15 on:** April 06, 2019, 11:06:38 AM »

Quote from: thebanker4 on April 06, 2019, 10:08:33 AM

These are very good guns at this price point. This is the first real issue that seems to be wide spread. I will contact Tan Keat at Nova Vista and let them know the poppet material is not suitable for this gun and it's very high pressure.

Hopefully, this will be the only serious issue with this gun. So far, it appear to be a pretty tough design as I have beat these gun up pretty good. Aside from this poppet material issue no other big problems.

Hopefully so, and will be interesting to see how NV responds, and how ATI handles the current stock of guns. Maybe some more $100 specials?

I sent a link to Ty at ATI, so he was aware of it.

We are only at the six month point. Even if someone makes a Delrin or Peek poppet for it, that will keep it out of the hands of non-DIY/tinkerer shooters. Like many of the discount PCP's, this one may need allot of love.

cosmic · « **Reply #16 on:** April 06, 2019, 11:28:06 AM »

Well I haven't looked at the original one .. I have one of Duy's valve and poppet in mine now.. Hopefully the manufacturer sends some out to ATI so the people that have one get a replacement..

nervoustrigger · « **Reply #17 on:** April 06, 2019, 11:37:22 AM »

Quote from: RDB on April 06, 2019, 09:45:47 AM

The poppet sealing material seems to be the same as the QB series rifles.

Precisely what I thought when I read the OP. The seal material embedded into the QB poppets appears to be polyurethane, perhaps 70 durometer. I have a couple that have been running at a 1500psi setpoint and I just knew they wouldn't last but they're still going strong for over 5 years now. So many variables though...operating pressure, throat diameter, seal material and hardness, and seat geometry. No doubt a Delrin or PEEK poppet would be just what the doctor ordered. The good news is it isn't necessary to have a tool shop to make a replacement. Here's a little walkthrough on how to make one with a drill or drill press.
https://www.gatewaytoairguns.org/GTA/index.php?topic=144959.msg1552409#msg1552409

FuzzyGrub · « **Reply #18 on:** April 08, 2019, 10:44:23 AM »

It would be great if someone can post all the poppet dimensions, such that those that are not leaking yet can get a heads up on making one, without having the gun tore apart.

darkcharisma · « **Reply #19 on:** April 08, 2019, 01:00:04 PM »

if someone is making a poppet. they really need to tear it apart. besides its so easy. degas, undo the barrel and unscrew the regulator and its right there. the only thing hard about this rifle is the valve. getting to the valve meant everything needs to come apart, almost.

stem od: 3mm or .116
stem length: 1.7695
poppet od: .353
poppet spring seat: .2785
poppet shell length: .298

the shell lengh can be shortened for less preload on the valve spring.

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ATI NOVA LIBERTY LEAKY POPPET and VALVE connection

Author Topic: ATI NOVA LIBERTY LEAKY POPPET and VALVE connection (Read 13545 times))