blurry black printing

[soozypoo]

hi,

ive had my canon pixma mg6450 for a couple of years now and everything has been fine until recently.

when i printed a letter ,the print came out like it was ghosting,trying to read it was like looking at text when you drunk.

if you change the colour of the print to say blue or red etc it prints perfectly.

i found that my son had got some paper jammed in the printer and not told me and he yanked it out so hubby thinks he may have damaged something,however i dont get why the other colours print fine.

I have ran all the usual ,nozzle checks,clean nozzles,deep clean.bottom tray clean,print head alignment,and cleaned the encoder film with a cotton swab and some isopropyl alcohol,when you print out a nozzle test it seems to be the pgbk one that is causing the problem,on the test sheet where it gives all the colours and the vertical blocks at the side,the pgbk one is not a rectangular bar it is bowed at the sides and the grid it prints is all uneven too. 

last night i removed and cleaned the print head to see if there had been an issue with ink leakage but putting it all back together this morning the problem still remains.

i dont use my printer that often so dont really want to buy another ,so just looking if there is anything i have missed that could be the cause,i dont know if it was my son ripping the paper jam out forcably that has caused this as it seemed to be fine until then.After the years warranty was up i did switch to compatible inks but again these worked fine until the paper jam issue.Wondering if its worth getting a genuine canon set to see if the issue still remains  

many thanks

[shadowsports]

Hi,

If it worked before the "forcible paper jam removal" incident with non genuine inks, then I doubt thats the problem. Sounds like unknown or hidden damage.   I'd hate for you to have to spend more $$ for a printer, but there isn't much more you can do if you've run the clean/deep clean, head alignment and taken the print head apart and reassembled things.      

Most of the articles I found relating to PGBK issues were all related to clogged nozzles and print head alignment, but you indicated you had a working machine until the paper jam.  Based on this,  I think you either have a serious clog, or some kind of damage due to mis-alighnment. 

PGBK on Canon

PGBK on 922