Some models of printers (mostly Epson) have their print heads built into the printer rather than as part of the cartridge. In this case, you should remove the cartridge and put 7-10 drops of isopropyl alcohol directly inside the head (where the ink from the cartridge normally flows to the printer).ccasionally, a printer will stop working, even though the cartridge obviously contains more ink. In this case, the problem typically has to do with clogged print heads. Obviously, the printer cartridge contains lots of ink, and the printer head has tiny holes that selectively place that ink wherever you need an image.