With our 7800/9800 refillable carts, you can use the cartridge by filling it 1/2 way with ink, but no matter the amount of ink the cart is filled with, the cartridge exit channel must be primed before installing into the printer for the best results.
If you have left your printer sitting unused for many months with pigment ink installed, then you will minimally need to shake all the carts to get ink in suspension, then after making sure carts are all at least 1/2 full and exit channels are filled with ink, do an Initial Fill or three Power Clean cycles to purge settled ink and get in-suspension ink from the shaken carts to the print head. After doing the initial fill or power clean cycles, it would be good to clean the printer's capping station, wiper blade, flushing box and bottom of the print head by following our instructions, here: http://www.inkjetmall.com/tech/content.php?133-Printer-Preventative-Maintenance
After manually cleaning your printer, do 1-3 regular cleaning cycles (to get ink flowing), print a nozzle check to see how things look (ideally, you should see 8 positions printing fully), then provided all positions are fully printing, print a test image. If all eight positions don't print fully/correctly, then you may be dealing with a stubborn print head or ink line clog, and/or blockage in the damper- in which case, you'd need to replace the dampers and/or flush the print head's internal micro-channels to try to get it printing well again.
I hope this helps, please let ,e know if you have questions or there's anything further I can help you with.
Best regards~ Dana