Mares first stage 'whistling'

[ferris213]

I had a set of mares Abyss 42 serviced and the first stage now 'whistles' when breathing from the regs. It only happens sometimes, and I can't hear it underwater. If you take a slight, gentle breath it doesn't do it, but if you take a steady, deeper breath it will.

The reg still seems to preform properly.

When I first picked up the regs from the shop, I asked the tech about it. At first he said it's normal, then said he would hang onto the regs and check them out. When I went to pick them up again he mentioned something about a teflon ring that had been installed incorrectly. (I may have misunderstood what he meant here)

They weren't whistling when I picked them up the second time, but have since done it a couple of times now and then.

I have spoken to the tech since and he insists it is a natural harmonics caused buy the air flowing through the first stage. To me, personally, this sounds like BS. But he says it's totally normal for some regs. He hasn't been able to answer why my regs started doing it only after he serviced them.

Does anyone have any thoughts or opinions as to what it is and what might be causing it? Is it normal or should I be concerned?

Thanks for your help.

 

[axxel57]

I had the same with some Abyss I serviced. Couldn't tell you how exact it comes, but every time I dismanteled the 1st stage again flipping the two springs and put it back together it was fine. I have no clue why and where the whisteling exact comes from, but it happens anyway not often. I guess you misunderstood the thing about a wrong installed teflon ring, I wouldn't know what the tech is referring to. Maybe he meant the plastic disc on which the main spring is sitting, but it would be difficult to install it wrong for a regulator tech I guess. Thanks for reading.....

 

[supergaijin]

whistling is usually associated with piston regs- some need a fair bit of lube. It's not as common with diaphragm 1st stages but could be that the diaphragm is vibrating inside the 1st stage. I am not a tech but I service my regs. I would open the diaphragm side, take it out and put it back and see if it made a difference. If you aren't confident doing this yourself, I'd go into the shop and ask- it's a 2min job.

 

[j2s]

Had the same 'problem' w/a used Apeks DS4, I had bought...Whistling was so loud other divers could hear it.....1st stage worked fine, took it apart, reassembled it and the whistling stopped......Didn't think any one else ever had that happen.....As far as the 'tech' who says it's 'normal' that's BS !!!!...It may or may not effect the proper performance of the equipment, but it's not 'normal' ...He probably thinks putting parts in backwards is 'normal' too....YO-YO :O !!!!!!.......Another reason for self-maintenance.......

 

[shephed]

Mine only whistles when pressure is under 700 psi. I thought it was a safety feature...

 

[Scuba Cat Diving]

I have heard many Mares regs doing this over the years, it doesn't seem to affect how they work, but is not right. Take it back again to the technician.
One of the first schools I worked for had Mares regs, the instructors used to joke was at least we can hear where the students are!!