So let me tell you about the washer stacks on those regulators. They are good for 25,000 shots, which I seriously doubt you've put through it. They are belleville spring washers made from tempered, high carbon spring steel with great ability to maintain deflection. Those regulators also have a piston inside of them with o-rings on both ends. A chain is only as strong as it's weakest link, and the weak link in every regulator are the o-rings. They typically use Buna-N 90 durometer o-rings. If it's a Huma reg, the o-rings are more than likely metric (this is speculative on my part since they are made overseas). But that's where I would look first. Get a list of o-rings from Huma. Regulator manufacturers know that eventually the reg will need to be maintained. So they freely divulge the o-ring sizes, as well as the belleville washer sizes and stack orientation. Huma is cool in that they will give you several washer stack orientations to achieve different power levels. There's no reg out that lets you go from (say) 50 BAR to 200 BAR. They usually allow for a 50-60 BAR tolerance within the washer stack configuration. So Huma has low power, medium power, and high power washer stack configurations. But just remember, the higher the power, the faster you wear out the o-rings. This is the 2nd Law of Thermodynamics. Reach out to Huma and ask for instructions how to maintenance the regulator. Also ask for o-rings sizes and washer stack configurations.
Buy replacement o-rings from the o-ring store ( www.theoringstore.com ). They are awesome. Here's my 2nd piece of advice. IF (emphasis on if) Huma uses standard size o-rings, and not metric, then abandon the 90 duro Buna-N and buy 90 duro Cast Desogrin Polyurethane o-rings. They aren't cheap, buy they are essentially forever o-rings. They are designed for EXTREME pressure environments. And when I say extreme, I mean up to 10,000 psi. They are the best of the best. They will cost 5x's as much as their Buna-N counterparts, but given the hassle of taking apart the reg and rebuilding it, you ideally want to do it as minimally often as allowable. The o-ring store has a TON of those o-rings in standard size. They have a few in metric, but very limited. They have any metric size in the Buna-N 90 Duro orings though. Just not the Polyurethane ones.
Hope that helps.
