Originally posted by Wrenchbender Ret.:
If you are getting black carbon on the plugs it is a rich carb condition. Make shure there is a passigway in the carb base gasket to the vacuum hole in the bottom of the carb. Pull the top off the carb & check the float level. Make shure there is no gas in the float. check the power valve piston. It should pull up & spring back & knock the ball off it,s seat.
That's what I originally thought in my case, but it seemed that no amount of carb cleaning/adjustment helped. As it turned out, it was the ignition system. The misses were causing a "rich" fuel/air mix resulting in plugs that were quickly coated in carbon. Since adding the HEI and new coil, no problems. I'm not saying it couldn't be a carb problem, it just seems that's where he has already been focusing with no good results.
Also, how have you been checking the dwell on the distributor, electronically or by setting the gap with a feeler gauge and placing the cap back on the distributor. In my case, I would set the gap, tighten the set screw, and put the cap back on, then watch the dwell angle rapidly change on my dwell meter. Have you checked the dwell angle (point gap) using a dwell meter or just with a feeler gauge?
