2-Ton,
I've got a 9500 cabover with a 637 in it, I've never had that issue but have had to rebuilt the carb. along with a new float. This summer I couldn't keep it running and the only way was to fill up the fuel filter and it would go till the fuel ran out(about 3 minutes), finally figured out that the pump would not draw from 1/2 a tank of fuel or less. So maybe I need a new fuel pump? did you have this issue before it started to leak? Is the pump on top not a self sealed unit (can't be opened)?
Steve
