So, I guess the question is twofold:

1) How should I test the clock bit in tach/clock thingie? I thought that the plastic gears were the only things that went, but apparently not.

2) I already tried testing it by running it off the car battery, after seeing this thread from Benzworld. At first I had no action, so then I readjusted the jumper cables and got sparking from the positive cable on the clock (). I immediately pulled the negative cable, and everything calmed down. Here is the picture from that Benzworld thread, with "a" being the place I hooked up the positive cable. Did I do any harm here?

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"Senior Luna, your sense of humor is still loco... but we love it, anyway." -rickymay ____ "Your sense of humor is still loco... " -MBeige ____ "Señor Luna, your sense of humor is quite järjetön" -Delibes

1982 300SD -- 211k, Texas car, tranny issues ____ 1979 240D 4-speed 234k -- turbo and tuned IP, third world taxi hot rod

2 Samuel 12:13: "David said to Nathan, “I have sinned against the Lord.” And Nathan said to David, “The Lord also has put away your sin; you shall not die."