[cleszkie]

I am assuming that you are talking about the ameter that is reading negative or discharge, not the voltmeter. If alternator is OK, then you have a short somewhere that is bleeding off the charge produced by the alternator. The short could be in the battery (bad cell) or elsewhere. The short is obviously bleeding off more juice than the alterantor can produce so it is a significant. The ignition should continue to work off the alternator even if the batter is removed.

On another note, are you running an externally regulated alternator? If so, check/replace your voltage regulator. Many charging issues can be solved with a new voltage regulator.