Black lines on all prints (Canon IP8750)

[GCIIMessi]

Hi! I've had this issue on and off for a while now, but the last few days it's been really bad.
I've added a picture of the type of problem I'm having. I'm getting black streaks on all prints (but not on nozzle checks etc). It usually happens at the top of the page then the rest prints perfectly. Any ideas as to what could be causing this?

I've tried all the maintenance options and manually cleaned the print head, but no change to the issue. Any help would be greatly appreciated!

 

[ElectricXpert]

Do the rubber rollers have smudges on them? I cleaned the rollers in a MX492.

 

[James Mike]

maybe whether there is ink pooling on the underside of the printhead/carriage assembly on first print? probably worthwhile to check the mechanism where the printhead gets parked/cleaned for gunk.

 

[The Hat]

Any help would be greatly appreciated!

Most likely there is a curl (bow) in the top of your paper, try gently curling the sheet the other way to straighten..

Also use the Custom printer settings to alter the height of the print head…

 

[PeterBJ]

I think the smearing could also be caused by ink on the underside of the printhead or the printhead carriage. This ink might come from a dirty purge unit. See this thread.

 

[GCIIMessi]

Most likely there is a curl (bow) in the top of your paper, try gently curling the sheet the other way to straighten..

Also use the Custom printer settings to alter the height of the print head…
View attachment 15670

I appear to be misisng the option of 'identify paper type'

 

[GCIIMessi]

Unsure if this can help clear up to see if anything is wrong inside of the printer or not, but adding these just incase!

 

[The Hat]

I appear to be misisng the option of 'identify paper type'

Forget about that option, it’s not needed to solve your problem..
And your purge unit looks pretty clean too..

 

[GCIIMessi]

Forget about that option, it’s not needed to solve your problem..
And your purge unit looks pretty clean too..

Sorry for all the questions. Is it normal to lose print quality when using 'prevent paper abrasion'?
The colours seem much different vs normal prints for me

 

[brwinters]

maybe whether there is ink pooling on the underside of the printhead/carriage assembly on first print? probably worthwhile to check the mechanism where the printhead gets parked/cleaned for gunk.

Had this issue on a P6000 at work and this turned out to be the issue. Years of use, daily cleaning cycles, and a wiper that's probably the original... led to a lot of crud on the print head. I widened the platen gap to band-aid the issue and discovered shortly after when I stumbled into an InkjetMall video on refurbing the P6000 series. It's a possibility here, though for me it always tended to happen towards the edge of paper where I assume the vacuum was weaker and it stuck up a bit from the rest of the paper. I've had lines in the middle of the print and that was because of curled heavyweight media.

View attachment 15671 I appear to be misisng the option of 'identify paper type'

I think he's talking about 'Prevent paper abrasion.' I assume this is some rudimentary platen gap adjustment?

Sorry for all the questions. Is it normal to lose print quality when using 'prevent paper abrasion'?
The colours seem much different vs normal prints for me

Your transport riding higher up from the paper would affect how the image is drawn onto the page. I'm sure the driver or firmware has a correction factor for this but it's probably something where your mileage would vary based on a number of variables.