HOG 2nd stage free flow help

[eelnoraa]

This HOG 2nd is my primay 2nd stage for my double setup. I bought it in December of last year, didn't start using it until April of this year. To date, I have about 10 dives. I have issue of free flowing. Here is the symdrone:

-when first pressurize, it is OK, no free flow
-when I take a breath or purge, air flow will NOT stop regardless of venturi switch's position. It just continously at a modorate rate. The flow is much slower than the purge, maybe about the same a normal breath flow
-once the free flow start, turning venturi switch has no effect of stopping it.
-the free flow can be stopped by turning in breathing effort knob by half turn. However, the next breath, free flow will start again. I can keep turning in the knob after each breath, but eventually, I run out of room on the knob.
-Free flow will still happen even the knob is all the way in. The flow rate is slower in this setting. Slow enough that I can manage to finish my dive today.

Based on the above, I thought this 2nd stage was adjusted too agreesive. But it is NOT the case. Here is the additional experiment I did when I got home:

-I adjusted the oralfice so that the breathing effort is very high. Even with this, once I start the air flow, it won't stop by itself
-I took off the front cover and purge buttom. If I activate the air flow by pushing the level, it won't stop by itself when I release level.
-The way to stop the air flow is 1)turn off the tank then turn back on. Or 2) turn in the adjustment knob. Once it stop, I can turn the knob back out.

This is very strange. It looks like spring is not strong enough to close the seat once air flow is started, but once the seat is close, the spring is good enough to hold it close. Or the balance chamber doesn't get enough pressure to assist the spring to close the seat. At this point, what can I do? Replace the spring? replace the white plastic piece inside the air tube? replace the seat? Consider how new this 2nd is, I dont think the soft part is the issue.

Any help is appreciated

 

[FoxHound]

If i'm not mistaken, if the I/P of your first stage is too high, it will cause a free flow of your second stage. I would check the IP of your first stage, set it appropriately, then adjust the second. That should solve your problem.

Or if you don't service your own gear, take it to a shop for a first and second stage adjustment.

 

[Pao]

I had a similar experience with an Apeks. Turned out to be a chewed up 2nd stage soft seat. It might also be creep on the 1st stage, but with creep purging usually brings down the IP - and stops the free flow - for a short while.

 

[Aqua-Andy]

I had a HOG 2nd do this exact thing. What I did was make sure the IP was set to 135PSI then re adjusted the 2nd. The problem still was there so I disassembled the second stage to inspect everything and found there was no detectable lube on the o-rings and the seat was pretty well grooved (yes I know how to adj these regs). I reassembled the reg with new soft parts properly lubing all parts and the problem started after a dive or two. I then replaced the Balance chamber and spring and that resolved the problem. I could not detect any problem with the parts but suspect the tolerances were out just enough to make the components stick under pressure. I would like to hear from Boss HOG on this matter just to see if there is another underlying issue.

 

[Jim Lapenta]

All of the advice above is good. It could be too high of an IP, improper adjustment of the orifice, lever height, or what Andy ran into. Without actually seeing the reg it's hard to say for sure. I do know that if the orings in the second stage are knicked, too dry, have too much lube, or show excessive wear this can happen. Things start sticking.

I just did a reg yesterday that was bought used and the second stage had some small corrosion in it as if it were not rinsed properly by the original owner.

All the metal parts went into the ultrasonic and the plastic in vinegar and water followed by a rinse with blue gold and then plain water. Then reassembly with all orings and seat replaced, properly lubed, and adjusted and it was all good.

I have not seen any issues myself with the piston/poppet, the white plastic thing, and have not heard of any. We'll see what Chris says when he sees this. I'll let him and Jack know about this thread.

 

[redacted]

I think I would be looking for something in the air barrel that is interfering with the poppet returning to the sealed (seated) position.

What happens when you cycle the lever repeatedly with the cover off? Does it always fail to seal? Does the leak always sound the same? I would be more suspicious of the plastic parts like the poppet and the balance chamber than the spring.

With the cover removed and the freeflow active, what happens if you lift the lever slightly?

 

[eelnoraa]

I measured IP with one of those small cheap IP gauge. It is between 135-140. Both first stages have similar IP, but backup 2nd stage is working properly. I also try swapping the 2nd stages, free flow follows the 2nd stage, not the first.

---------- Post Merged at 10:59 AM ---------- Previous Post was at 10:55 AM ----------

...Things start sticking.

I just did a reg yesterday that was bought used and the second stage had some small corrosion in it as if it were not rinsed properly by the original owner.

All the metal parts went into the ultrasonic and the plastic in vinegar and water followed by a rinse with blue gold and then plain water. Then reassembly with all orings and seat replaced, properly lubed, and adjusted and it was all good.

I think "sticking" is a good description of what it feels like. But this reg is just spanking new. I haven't disemble it further than taking the front cover and purge diaphram off. I can see all metal parts are shiny. The reg appears to be clean free of debrids. I wonder if I should dissemble the air barrel, and try to clean and lube the poppet.

---------- Post Merged at 11:09 AM ---------- Previous Post was at 10:55 AM ----------

I think I would be looking for something in the air barrel that is interfering with the poppet returning to the sealed (seated) position.

What happens when you cycle the lever repeatedly with the cover off? Does it always fail to seal? Does the leak always sound the same? I would be more suspicious of the plastic parts like the poppet and the balance chamber than the spring.

With the cover removed and the freeflow active, what happens if you lift the lever slightly?

With front dover off and cycling the level, the reg fails to seal 9 out of 10 times. The leak is not strong like a purge, but big enough that I can detect it with my Otterbay 12mm hood on. When I lift the lever, I can usually stop the leak. But I don't think it is the level, I can bump the reg, smack it with my palm, turn the knob ... It seems it just need a "kick" to reseal. I am thinking something interfering the poppet too, so my next step will be taking the barrel part for clean and lube.

 

[SDAnderson]

I measured IP with one of those small cheap IP gauge. It is between 135-140. Both first stages have similar IP, but backup 2nd stage is working properly. I also try swapping the 2nd stages, free flow follows the 2nd stage, not the first.

---------- Post Merged at 10:59 AM ---------- Previous Post was at 10:55 AM ----------



I think "sticking" is a good description of what it feels like. But this reg is just spanking new. I haven't disemble it further than taking the front cover and purge diaphram off. I can see all metal parts are shiny. The reg appears to be clean free of debrids. I wonder if I should dissemble the air barrel, and try to clean and lube the poppet.

---------- Post Merged at 11:09 AM ---------- Previous Post was at 10:55 AM ----------



With front dover off and cycling the level, the reg fails to seal 9 out of 10 times. The leak is not strong like a purge, but big enough that I can detect it with my Otterbay 12mm hood on. When I lift the lever, I can usually stop the leak. But I don't think it is the level, I can bump the reg, smack it with my palm, turn the knob ... It seems it just need a "kick" to reseal. I am thinking something interfering the poppet too, so my next step will be taking the barrel part for clean and lube.

Swap the soft seats in the second stages and see if the problem follows the seat. My guess is that the problem is a small ding or centering problem in the HP seat in the first stage, but it can definitely be a bunch of things.

 

[cerich]

easier yet, send me the reg and I'll send you another. If it has never been wet it for sure is my problem to fix.

 

[eelnoraa]

Wow, Chris, I don't know what to say. Thank you for your very genuous offer.

I just want to point out that this 2nd stage has been wet. I bought it back in December of 2011, has been using it for about 10 dives, so not exactly brand new. I will PM you.