I have run itothis situation before with the same symptoms. Mine was a kink in the one Bev line. It would sometimes flow okay, but still restricted,...
Lol, my only worry about neon green dye in the glycol would be the enviro-nazi that would inevitably see it leaking on the floor, ten minutes before...
I have run into several pumps over the years with missing or defaced name plates. Can be a major PITA for sure, but usually just the electrical side....