When I purchased my new Silver Bach it came with a Grime Gutter attached to bottom of my valve casing and when I removed it, I noticed black guck on the valves from the Grome Gutter.
It looks like some of the silicon came off the grime gutter and stuck on the valve casing and bottom caps. I have been trying to remove it and it won't come off.
I took it to a place and the tried to brush it off and could get it all off. I only use soap and warm water to clean my trumpet. Any suggestions on how I can get this guck off?