You guys are the greatest! All of your suggestions sound excellent and right on the money. The brown sludge is probably just condensation (and we've been getting crazy weather here in New Jersey lately).

I have just one more question and figure I'll ask here while we are talking about the B20. I get an occasional "tap" in my engine, like a valve tap, when I push it hard (like high speeds on the highway, climbing long hills, etc.), that will go away as I slow down or not push the gas as hard. The tapping can't be heard while ideling, only when I really get on the gas. Could it be a weak/sticky valve/lifter or maybe I just need to have the valves adjusted? How often should the valves be adjusted?