Digital BW, The Print

I have had some stubborn clogs but have always been able to get them to
break loose.  Are you using the large 60cc syringe?  The small ones just
don't create enough vacuum.  I would max out the vacuum and hold it for 30
seconds, then do a couple of quick pull and releases on the syringe and then
hold again for 30 seconds at max vacuum.  Things eventually broke free.

Doug