Avenger regulator teardown

[n4spd]

Tried to clean up my avenger .25 regulator so here's a quick teardown:

1. De-gas, remove plastic cover to access regulator adjuster.


2. Tap safety pin out of the way and unscrew to remove the adjuster


3. The other end of the adjuster has the delrin? seal.  The seal has concentric circles/grooves so probably parted from lathe without polishing afterwards.


4. The seal is recessed inside the brass shaft so I had to make a probe to polish it.  Chuck shaft to lathe, probe to tailstock to polish.


5. The adjuster is actually the entire regulator and the shaft moves in/out.  When spun on the lathe, the shaft wobbles so maybe another source of leak depending on how the adjuster is clocked.


While it's open, I changed both o-rings on the regulator.  The closest I could find in my inventory was
buna-n 006 and buna-n 009 in 90 durometer.  Slightly off in size but they seem to work.

Put it all back together, added some air and put some soapy water over all 3 openings.  Found 3 slight leaks in the pressure release and burst disc.


Teflon tape on the threads of the burst disc and outside threads of the pressure release cap fixed 2 leaks.  The actual pressure release set screw just sits flush against the bottom covering a vent hole so I put an o-ring down there and tightened set screw on top of it.  It still has a very very slow leak from the set screw probably because o-ring is just mashed up so I'm going use lathe to cut a recess to fit an o-ring at end of set screw.

So far, the regulator creep has gone from 500psi to 200psi, but I need more testing because I think it varies with how the regulator is clocked and maybe pressure too...

[Bob Pratl]

Robert, thanks, very useful information. Where you having problems or did you just want to see how it functions?

[FuzzyGrub]

Definetly a different design than the Liberty.

On the Liberty, the O-rings on the spool were a standard metric size.  but some of sealing O-rings around the reg were custom metric sizes.   You couldn't find them in same material and size. 

[Tpatner412]

Just for reference, the reg orings are metric. The larger of the two is 4x2mm. For the small one, I’d recommend using a 005. It’s the closest you’ll be able to find to the factory size.

[FuzzyGrub]

Just for reference, the reg orings are metric. The larger of the two is 4x2mm. For the small one, I’d recommend using a 005. It’s the closest you’ll be able to find to the factory size.

Tyler,

Are there schematics, with O-ring sizes, for the Avenger available?  or in the near future? 

[n4spd]

Mine had regulator creep of 500psi.  I set it to 2400 psi and it would move to 2900psi overnight.

The barrel on mine is awesome.

It didn't have any leaks (at least noticeable) upon arrival.

I noticed a slow leak recently so I decided to tackle the regulator at the same time.

Hopefully it's not a leaking poppet that happens over time like the nova liberty.

Robert, thanks, very useful information. Where you having problems or did you just want to see how it functions?

[n4spd]

Thanks for the info!  The 006 was so hard to put on, I can't imagine the sweat trying put on a 005.

Just for reference, the reg orings are metric. The larger of the two is 4x2mm. For the small one, I’d recommend using a 005. It’s the closest you’ll be able to find to the factory size.

[Motorhead]

Indeed the sealing surfaces of the regulators SEAT control how stable the set point is.  Accuracy here in making sure surfaces are VERY smooth, Flat and Parallel to one another is key !!

If the spool does not spin perfectly true ? then the seat surface is not staying centered to it mating half.  Again accuracy here is paramount.

Having serviced, modified and tweaked on 100's of regulators this comes as fact not opinion.

Scott S

[FuzzyGrub]

They are typically Poly 90D.  The small 90D O-rings are "fun" to try to streach. 

[nervoustrigger]

Very good play-by-play.  I like that you're dealing with the valve seat to address creep, particularly since this design is more challenging than most.  On another forum there are a lot of topics about creep, and for months and months I've been trying to educate people on how to deal with it but apparently the idea is about as appealing as picking up a dirty diaper.  No telling how many OEM regulators have been replaced with an aftermarket one for this reason.

Regarding getting small 90D O-rings installed, it helps to add a little heat from a hair dryer or soak it in hot water.  The -008 on the end of a Ninja reg is a particularly fun one due to the raised lip it has to pass over.  Turns out an ink pen body works nicely to press down on it with a lot of force without risking damaging it.  In other places I sometimes end up making a small tool if I can’t improvise something. 

[oldpro]

Indeed the sealing surfaces of the regulators SEAT control how stable the set point is.  Accuracy here in making sure surfaces are VERY smooth, Flat and Parallel to one another is key !!

If the spool does not spin perfectly true ? then the seat surface is not staying centered to it mating half.  Again accuracy here is paramount.

Having serviced, modified and tweaked on 100's of regulators this comes as fact not opinion.

Scott S

What Scott said and lets not forget the material the disk is made of. Some to hard materials wont seat well and some to soft will warp.

[Tpatner412]

Very good play-by-play.  I like that you're dealing with the valve seat to address creep, particularly since this design is more challenging than most.  On another forum there are a lot of topics about creep, and for months and months I've been trying to educate people on how to deal with it but apparently the idea is about as appealing as picking up a dirty diaper.  No telling how many OEM regulators have been replaced with an aftermarket one for this reason.

Regarding getting small 90D O-rings installed, it helps to add a little heat from a hair dryer or soak it in hot water.  The -008 on the end of a Ninja reg is a particularly fun one due to the raised lip it has to pass over.  Turns out an ink pen body works nicely to press down on it with a lot of force without risking damaging it.  In other places I sometimes end up making a small tool if I can’t improvise something. 

FWIW, I have been using 70D orings on the few avenger regs I have resealed with no issues thus far.  But I should say the factory orings are 90D due to the higher pressure the gun can handle (typically 70D orings are not rated for use up to 4300 PSI).  So long as the seats look good, I have not been messing with them. But yes, absolutely an essential piece of the equation. We do have replacements if they are needed. 

[OTmachine]

It still has a very very slow leak from the set screw probably because o-ring is just mashed up so I'm going use lathe to cut a recess to fit an o-ring at end of set screw.

I believe mine has this problem also.  Happened after I adjusted the reg. 
Have you thought about using a spacer ring to keep from squashing the o-ring and keeping it in place?

[n4spd]

Why did you have to reseal those avengers?

FWIW, I have been using 70D orings on the few avenger regs I have resealed with no issues thus far.

[n4spd]

Sorta like that...  I just punched out a round disc from an old used bike tube and dropped it down there.  Much better than squishing an o-ring.  The set screw has a flat/flush end so works out well.  De-gas still works.

It still has a very very slow leak from the set screw probably because o-ring is just mashed up so I'm going use lathe to cut a recess to fit an o-ring at end of set screw.

I believe mine has this problem also.  Happened after I adjusted the reg. 
Have you thought about using a spacer ring to keep from squashing the o-ring and keeping it in place?

[OTmachine]

Sorta like that...  I just punched out a round disc from an old used bike tube and dropped it down there.  Much better than squishing an o-ring.  The set screw has a flat/flush end so works out well.  De-gas still works.

[quote author=n4spd link=topic=177140.msg156006105#msg156006105 date=1597906447
Thanks for the tip.
Keith

[Tpatner412]

Why did you have to reseal those avengers?

FWIW, I have been using 70D orings on the few avenger regs I have resealed with no issues thus far.

Two of the guns I was playing with/adjusting outside the parameters laid out in the manual, and eventually both developed a few hundred psi creep (Took about 6 months before they started creeping).  Another was my own personal .177 avenger that had some creep out of the box (maybe 200 psi), which wasn't really enough to cause me issues over the chrono or downrange with the settings I had, but decided to try and get rid of it with good results so far.  The other was for a friend who bought one.  His was creeping right out of the box (maybe 500 psi over an hour or two), so tore it down, replaced the seals and seat, and it has been all good since. 

[n4spd]

How did you replace that seat, since it's recessed?

I contacted Air Venturi and they insisted that it can NOT EVER leak from the delrin seal in the regulator!
They were/are of no help so far.

Robert

replaced the seals and seat, and it has been all good since.

[nervoustrigger]

I don’t have an Avenger but usually there is a through hole to the seat so you can punch it out from behind. 

BTW supposedly the manual says to evacuate the reservoir before adjusting the regulator.  Generally it’s okay to increase a regulator’s setpoint while under pressure because you are backing the seat away from the piston and allowing it to bring up the plenum pressure in a normal manner.  However, attempting to lower the setpoint while pressurized drives the seat into the piston and may damage it, causing inconsistent regulation and creep.  I just wanted to mention it as a reminder to those referencing this thread.

[Tpatner412]

How did you replace that seat, since it's recessed?

I contacted Air Venturi and they insisted that it can NOT EVER leak from the delrin seal in the regulator!
They were/are of no help so far.

Robert

replaced the seals and seat, and it has been all good since.

Dug the original out with a dental pick.  Mangled it pretty bad.  Was initially planning to try and flip it, but tore it up so bad I had to replace it.  Quite honestly, not sure it was the seat or the orings leaking, should've done one, then the other if the creep stayed....but I decided to do it all in one shot. 

Very few Avengers have come back thus far, so I suspect they haven't seen one leaking from the seat yet (or with a damaged seat for that matter). 

I don’t have an Avenger but usually there is a through hole to the seat so you can punch it out from behind. 

BTW supposedly the manual says to evacuate the reservoir before adjusting the regulator.  Generally it’s okay to increase a regulator’s setpoint while under pressure because you are backing the seat away from the piston and allowing it to bring up the plenum pressure in a normal manner.  However, attempting to lower the setpoint while pressurized drives the seat into the piston and may damage it, causing inconsistent regulation and creep.  I just wanted to mention it as a reminder to those referencing this thread.

Yes, this is absolutely correct.  Degas the gun before adjusting down.  No need to degas if increasing the reg pressure (up to 3000 psi).