Deep 6 1st stage IP adjustment: Down after seat set?

[MichaelMc]

From the Deep6 manual under troubleshooting, if the IP is low, you should adjust it up. But if it is high or creeping, you should replace the HP seat and rebuild. Does this imply that once initially set that the IP should only be adjusted further up, and not down?

I come to this question as, out of curiosity with compatibility with the low IP of a Poseidon XStream, I adjusted mine down to the 125 range and likely may have turned it out even lower. After returning it to 135 (on a lowish pressure tank) it then had unbounded creep if tank pressure was above about 1800. I was careful to purge or breath while adjusting and reinstalled the environmental cap while (lowish) pressurized. Nothing looks remiss after complete disassembly, short of a magnifying glass. I was curious if the likely cause is the large change to the IP or some error of mine in not purging during adjustment. It worked great prior to my little IP range experiment, .

Reassembly with the spare service parts kit is pending on a torque wrench decision. Thanks.

 

[rsingler]

From the manual under troubleshooting, if the IP is low, you should adjust it up. But if it is high or creeping, you should replace the HP seat and rebuild. Does this imply that once initially set that the IP should only be adjusted further up, and not down?

In short, no.
Low IP is an adjustment problem.
High IP is an adjustment problem.
IP creep is a leak at the HP seat, or at the balance chamber o-ring.

There should have been no issue with lowering IP to match an XStream second stage, nor with raising it back up.
Both adjustments are external, done with the hex key, after removing the environmental diaphragm, as you described.
But if you disassembled the reg, the HP seat may no longer be mating in the groove created by its contact with the orifice, and might thus leak. Try a new HP seat.
If you didn't disassemble/reassemble the reg, I can't suggest a cause without more information. How much creep is "unbounded"? Try repeated brisk purging, or even "flushing" by opening the tank valve a few times with no second stage attached to your first stage's low pressure port. Then try "slam closing" the first stage valve by briskly opening the tank valve on a full tank, with a second stage attached. There may have been a particle caught between the orifice and the HP seat causing your IP creep.
Hope this helps!

 

[MichaelMc]

Thanks rsingler, I think reassembly will tell me that it was the seat somehow, once I assemble all the tools. Regs have been fine prior.

I had only removed the env cap and adjusted IP down then back up, then replaced cap with reg pressurized, on a used tank. But with a new tank got consistent free flow or pop the over pressure valve of my IP gauge after a pause, IP raise rate was not extreme but steady 1-2 PSI/second say till my IP OP pops at 230 or so. But only with tank pressures over ~1800. Both with env cap still on and with it removed before any further disassembly.

There were small water beads in the HP chamber, so I believe I got a wet fill or introduced some, but problem occurred over 2-3 tanks, which would not all have been wet.

 

[MichaelMc]

Unbounded was til my IP gauge relieved pressure at about 230, or my balanced 109 did.

Something stuck in the seat is a good idea... Reg is in pieces on the table, so it may remain a mystery. Good ideas for any general reg trouble shooting in the future. Air is pure until it is not. That filter screen looks fairly fine.

 

[rsingler]

Yeah, that sounds like a leak at the seat or oring. HP seat shaft o-ring (that little tiny one inside the balance chamber) seems more likely, since it is tank pressure related. The seat itself should seal tighter with rising IP or tank pressure, unless there's a seat scratch or flaw that cracked early in its life. Look at seat face under loupes or magnifying glass.

 

[MichaelMc]

I'll get a loupe and report back. Thanks.

 

[Bigbella]

I'd also agree that it's a HP seat issue. In the previous first stages, prior to the Xstream -- the 2900s through the 3900s -- an even slightly damaged piston would, in turn, damage the seat; wreak havoc with the IP; and lead to serial seat replacements.

It should be noted that the current Poseidon field repair manual requires a tank to be at a minimum pressure of 190 bar / 2610 psi for setting IP . . .

 

[MichaelMc]

The first stage in question is a Deep6 Signature, not a Poseidon. I was just testing the Deep6 IP down to the bottom of the range in the Deep6 manual. And possibly ineptly adjusting a bit below that. I did that to confirm for a match to the range of a possible future Xstream second stage.

Some inconclusive results: The HP seat had a 20 degree region of the indent from the orifice that looked more rough and a bit wider than the rest, under a 10x loupe. The balance chamber shaft and HP o-ring looked fine. No signs of foreign debris, but I did not preserve their state when I removed them, aside from setting them in order on the table.

I'll report back once I reassemble it, which I expect will go fine, with torque wrench, gloves, lube syringe, etc. The 18mm 10x Hastings triplet loupe I got was nice, but more power might be helpful, and with leds next time.

 

[davetowz]

1st.. You cannot use specs from deep 6 for a Poseidon. You are over analyzing an issue. maybe you should take the regs to someone who has an idea of what to do. Unless these are regs you are just playing with to learn on.

 

[guruboy]

1st.. You cannot use specs from deep 6 for a Poseidon. You are over analyzing an issue. maybe you should take the regs to someone who has an idea of what to do. Unless these are regs you are just playing with to learn on.

Perhaps you should re-read the thread until you understand what is going on before you comment again.