Duster Brake Combinbation/ Prop Valve

Dana67Dart said

Have you tried to clean it up (brass wire wheel)

That looks like the desolved remnants of a seal / O ring.

Click to expand...

Granted some of it was however the brass is damaged and knurled over one one spot. I did have to apply heat when removing some of the flare fittings and maybe I contributed to its demise but nothing else in the unit is damaged.