I check the advance and it moves freely, and when I rev the engine up a little with the timing light in it the mark advances as it should. I double checked the distributor gear and at tdc on compression stroke it's pointing at #1. I bought a new cap and rotor button today and think I discovered my problem. Pulled a wire off the old cap and went to put it on the new one and the 90 degree bend In the boot doesn't reach the terminal in the cap by about 1/8 inch. So my guess is the spark has been too hot since I changed those wires and because of this then advance is trying to retard itself to compensate. Stupid mistake on my part.