Are HOG regulators good or problem?

[boriss]

That bulging enviro disc is a problem waiting to happen. I would check the IP. If it's good and not creeping, what is most likely to cause that is a leaky diaphragm on the 1st stage.
OR someone took the envirocap and seal off when the reg was not pressurized and screwed it back on.
Leaky diaphragm will also result in champagne bubbles between the cap and diaphragm retainer (chrome part) and between the chrome part and the body.
Keep using it like that and the seal at some point is going to blow out.
In order to get a good seal the reg needs to be pressurized before the cap and seal is put back on.
You never remove and replace the seal on a HOG 1st stage that is not pressurized.
That seal is so deformed that it probably isn't sealing and you are getting water in the balance chamber.
Won't hurt the reg if you are diving fresh water. If you are using this in salt, it will corrode the hell out of everything under the cap.
I would not use that reg until you get it looked at.
How do I know?
Well, I wrote the first draft of the service manual for the D3 and taught the reg tech class for 10 years. And I've probably serviced 200 HOG D3 1st stages and seen much of what can happen with regular wear and tear and with abuse and poor care.

Good eye! I checked my other D3 1st stage and it's not popping out like that. Weird. Thanks for all the info!! I'll have to get it serviced ASAP.

EDIT: I found a random picture on my phone from when they were new and neither had a bulge.