Naptha or lacquer thinner
Glen, I have had some sappy issues while turning pine or tamarac and when I want to stop the ooze I clean the sap up with some Naptha or lacquer thinner. If it is in a crack or crevis an old toothbrush can be used to get in the cracks and remove the sap. On the turnings I then fill with CA and sanding dust to level it out. In your case just getting the sap out of the knots may do the trick, but the CA glue would seal it off. It kind of sucks to have to go in and do it when the chest is complete, but as they say; hindsight is 20-20!
Hope this helps,
Jeff