Rebuild Your Regulator Before You Throw It Out!!!!!! Harris Repair 

The leaves are from a flying bug called a ''leaf roller'' for the apparent reason. They accessed the inside by the vent hole in the screw on cover, they love to find holes in anything about .125 inches and then pack them full and lay their eggs in the leaves.

Thanks for taking the time to create and post this, gave me the confidence to tackle my own.

Teflon tape is not recommended for gas applications, fine bits of it can find their way into jets, orifices, pilot holes, etc. A good grade of pipe sealer used extremely sparingly is best. Also, beware of RTV. Also glass covered gauges are no longer permitted in commercial applications. Almost forgot (not good) never any grease or flammable material around oxygen gear fire or explosion!

I don't scrap regulator cores since they sell on Ebay. Seal-Seat has a comprehensive catalog for old equipment if kits don't turn up from other sources, and you can also send them out for overhaul to online rebuilders or via your local welding supply. I overhaul most of mine but when I get a really crusty oxygen regulator I send those out to let someone else clean up the brass as my time is worth the few dollars over a kit cost and shipping. I don't buy new regulators or torches, only cutting tips and get most of those online too. I collect and overhaul torches and regs for myself per factory tech data and keep an eye out for them and for gas cylinders (know what you can exchange locally) which I snag often for less than the gas inside them is worth. I never run out on a weekend and after doing this about ten years I casually accumulated about 30 cylinders (they don't depreciate and I've plenty of space so why not?) in nearly all sizes.

Are those 2 1/2" gauges?