Repairing an HP PhotoSmart 6525 Printer Not Printing Black Ink

I will continue to run some more tests with this and see if it can get back to tip-top shape! It may need a hotter liquid mixture to really get flowing again. I hope this helps you, particularly if you need to take apart your printer to get to the printhead. I have also seen that new printheads are available on eBay for ~$25.
EDIT: 9/16/21 - I ended up selling this printer for $35+$21 shipping!
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