Dust cap off first stage while soaking regs

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Any water inside a first stage that is allowed to just sit there is always a bad idea and can cause damage.
If you must soak your first stage, at least do it when the regulator is on a cylinder (turned on).
If you don't think that water inside your first stage is not damaging, then go ahead and keep doing what you are doing.

What damage does clean fresh water do inside a first stage? If it is easier, perhaps we should specifically consider a balanced piston first stage. What part(s) are damaged and what is the nature of that damage?

EDIT: Well I can think of one problem that would be exacerbated by even FW exposure. Older Scubapro MKk20s had a brass piston with a brass tip (no chrome) engaging the HP seat. The sealing surfaace had problems with tarnish causing IP instability. They needed a good cleaning of the piston tip about every 6 months. It would probably be hard to find any today that have not ben switched out to the current composit piston.
 
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What damage does clean fresh water do inside a first stage? If it is easier, perhaps we should specifically consider a balanced piston first stage. What part(s) are damaged and what is the nature of that damage?

EDIT: Well I can think of one problem that would be exacerbated by even FW exposure. Older Scubapro MKk20s had a brass piston with a brass tip (no chrome) engaging the HP seat. The sealing surfaace had problems with tarnish causing IP instability. They needed a good cleaning of the piston tip about every 6 months. It would probably be hard to find any today that have not ben switched out to the current composit piston.

So here's the problem, can't really verify without doing an experiment what damage only FRESH water would do. Might have to find an old piston reg that I can do a long term experiment on with fresh water intrusion. Problem is, unless you use distilled water, fresh water from the tap can have all kinds of minerals or additives in it. So I am sure that would at least possibly leave a residue inside the first stage, depending on how much water got in. Salt water intrusion could leave a residue inside once it dries. You are right though, manufacturers are making pistons with better materials now than 20 years ago. I have a MK20 myself that is my primary warm water setup.
Personally, I have never liked piston regs BECAUSE they are more prone to corrosion than diaphragms.
I guess I am more of a "better safe than sorry" kind of guy.
 
I have the Legend LX. Bought brand new.

Doesn't it have the ACD???? If it does, and I think that it does, you have nothing to worry about, no water has gotten in the first stage per the design of the ACD!!!!!!

BTW, I consider diving in fresh water (quarries, lakes, etc.) as rising my equipment after diving in salt water and thus I don't bother with rising the equipment after I get home at all (assuming the the fresh water is clean and not contaminated).
 
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As much as I hate to admit it, I agree with @halocline , rinsing by itself isn't good enough, one must let equipment soak in clean fresh water after diving in salt water.
 
yup - its a DUST cap. its not designed to be a bulletproof waterproof cap

... it depends on the reg type and the style of cap being used. Many are quite waterproof.

... Bob (Grateful Diver)
 
Any water inside a first stage that is allowed to just sit there is always a bad idea and can cause damage.
If you must soak your first stage, at least do it when the regulator is on a cylinder (turned on).
If you don't think that water inside your first stage is not damaging, then go ahead and keep doing what you are doing.

I've been soaking my regs for 15 years ... over 3,800 dives so far ... and haven't seen this damage you're referring to. Even on those rare occasions when I forgot to put the dust cap in place, removing the HP hose and blowing out the reg sufficed. Salt water inside a first stage is damaging ... fresh tap water, not so much. Just use one of the methods described earlier in this thread to remove any residual water from inside the first stage.

... Bob (Grateful Diver)
 
The only reason to soak in a tub is to check for air leaks. A hose wash down will get as much or more salt off than any soaking.
 
So here's the problem, can't really verify without doing an experiment what damage only FRESH water would do. Might have to find an old piston reg that I can do a long term experiment on with fresh water intrusion. Problem is, unless you use distilled water, fresh water from the tap can have all kinds of minerals or additives in it. So I am sure that would at least possibly leave a residue inside the first stage, depending on how much water got in. Salt water intrusion could leave a residue inside once it dries. You are right though, manufacturers are making pistons with better materials now than 20 years ago. I have a MK20 myself that is my primary warm water setup.
Personally, I have never liked piston regs BECAUSE they are more prone to corrosion than diaphragms.
I guess I am more of a "better safe than sorry" kind of guy.

While I don't really see parts damage as a problem, I would be concerned about any science experiment that may develop inside a reg (1st or 2ndf stage) that is routinely put up wet. I really don't see how rinsing can possibly remove salt water from vulnerable nooks and crannies; but whether you rinse or soak to effectively remove the salt, as long as you dry them well before storage, they should be fine. The alternative is to be lucky enough to dive them so often that they get rinsed frequently and never really dry.
 
Strangely Aqua Lung recommends soaking.

6. USER CARE & MAINTENANCE
It is important to provide the proper preventative maintenance in order to
ensure the best possible performance and maximum life of your Aqua Lung
Regulator. The following maintenance procedures should be performed routi-
nely after each use to ensure that the regulator is cleaned, inspected, and pre-
pared for the next use or for storage.
As soon as possible after diving, the regulator should be rinsed thoroughly with
fresh water while it is attached to a cylinder and pressurized with air.
Rinsing alone, however, will not sufficiently clean the regulator. To clean the
regulator as thoroughly as possible Aqua Lung recommends:
. Attach the regulator to a charged SCUBA cylinder, open the cylinder valve to
pressurize the regulator, and thoroughly soak both the first and second-stages
in a bath of fresh water.
. While the regulator is soaking, move the vane adjustment switch on the
second stage (if present) back and forth several times from the “MIN” (or “—”)
to the “MAX” (or “+”) settings. You may also turn the valve adjustment knob
(adjustable models) slightly back and forth—no more than 1/4 turn.
After the regulator has been properly soaked, it is important to rinse it vigo-
rously by flushing the mainspring cavity of the first stage regulator (non-environ-
mentally sealed models only), the second-stage mouthpiece, and the openings
in the second-stage front cover with a pressurized stream of water. This will
remove the deposits of salt and minerals that were loosened during soaking.
 
Gott
Attach the regulator to a charged SCUBA cylinder, open the cylinder valve to
pressurize the regulator, and thoroughly soak both the first and second-stages
in a bath of fresh water.

Got to love that advice. You read it all the time. Like everyone has a HUGE tub that will hold a cylinder and reg for 'safe' soaking. Sure, it's probably best, but face it, mostly impractical and a major PITA. I don't know anyone that does this.
I've been soaking in a laundry sink or transport tub for 20 years. Seems to work. :)
Good DUST CAPS are WATER TIGHT.....easily. This is simply a non-issue. If yours is not, get a decent one. :stirpot:

Sure, like everyone, once every couple years or so it gets thrown in with the cap off (damn! :(). Remove hoses, blow it out, go on with your diving. :thumb:

I HAVE taken them apart after doing this. They didn't soak long with the cap off, but nothing, absolutely nothing was in the HP chamber or anywhere else I could find.The filter gets a little wet but seems to block most of the water.

As I do overhaul my own regs, I recall mmmm something about rinsing the parts with (gasp :confused:) fresh water :shocked:, before drying and assembling. What do the paranoid people think fresh water is actually going to do? Dissolve O-rings and corrode chromed brass? :rolleyes: :idk: :facepalm:

Kudos to [awap] for the reminder about unbalanced pistons. :cheers:
 
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