MP520 won't print black ink

Alcohol is not the way to clean a print head. Simply run the hottest tap water into the ink inlet and print head for several seconds. Since print heads create heat to form the ink droplets needed to form a letter or graphic; running hot water will not DAMAGE the sensitive heads. Alcohol is fine for removing a film (Like fingerprints) from the surface and contacts, but not to be used internally within the head itself.
May as well get a new Black Cart now.

Use the printer's utility program to self-clean the printer. This process may need to be repeated as many as 5 to 10 times. Often this will resolve the problem.

Turn the printer off, preferably overnight, if the self-cleaning utility has not worked. The ink may need to soften before the self-cleaning utility will be successful. Turn the printer on and try the self-cleaning utility again several times.

Determine from the owner's manual where the print head is located. Epson printers, for example, are usually in the printer. Many other brands place the print head in the cartridge.

Remove the cartridge. For models where the print head is in the printer, drop seven to 10 drops of isopropyl alcohol (rubbing alcohol) down the ink receptacle area. This is the hole where the ink flows into the head from the cartridge. Run a few self-cleaning utilities. If necessary, allow to sit a few hours or overnight and repeat the self-cleaning utility.

Soak the cartridge print head in hot water if the print head is in the cartridge. Allow to soak overnight. Dry the print head area with a paper towel. Repeat the self-cleaning utility.

Place the cartridge print head in isopropyl alcohol if the hot water soak did not unclog the print head. Leave the print head covered in alcohol overnight. Use a damp paper towel to wipe off the print head area. Dry carefully. Try the self-cleaning utility again.

Purchase a new cartridge if the alcohol soak did not unclog the print head in the cartridge. This will provide new print heads that won't be clogged. Contact a service technician for repair of print heads in the printer if the alcohol did not unclog the print head.

Try putting a bit of isopropyl alcohol in the bottom of the cartridge holder where the ink goes through and letting it sit for a couple hours then putting the cartridges back in and running the cleaning cycle a few times.

The alcohol should help dissolve the dried ink in the print head.

Hello
Yes you can repair by trying the following steps:-
Remove the cartridge. For models where the print head is in the printer, drop seven to 10 drops of isopropyl alcohol (rubbing alcohol) down the ink receptacle area. This is the hole where the ink flows into the head from the cartridge. Run a few self-cleaning utilities. If necessary, allow to sit a few hours or overnight and repeat the self-cleaning utility.
Soak the cartridge print head in hot water if the print head is in the cartridge. Allow to soak overnight. Dry the print head area with a paper towel. Repeat the self-cleaning utility.
Place the cartridge print head in isopropyl alcohol if the hot water soak did not unclog the print head. Leave the print head covered in alcohol overnight. Use a damp paper towel to wipe off the print head area. Dry carefully. Try the self-cleaning utility again.
Hope it helps, if so do rate the solution
good luck

If the self-cleaning cycle does not solve the problem, try turning the printer off overnight to allow the ink to soften. Turn the printer on the next day and try printing a test pattern to see whether the problem has either disappeared or become less noticeable. This ink-saving procedure can work effectively because sometimes the dried ink on the print head needs time to soften before the printer head can be cleaned completely. Try running the self-cleaning utility again one or more times.
Steps for Manually Cleaning the Printer Head

If the overnight cleaning still does not work, there may be a layer of thick ink that is blocking the holes of the printer's head. The next option is to manually clean the printer head. Follow these steps:

* Determine from the owner's manual where the print head is located.
* Remove the ink cartridge from your printer and then dip a cotton swab in hot water or isopropyl alcohol and rub it against the print head. This should loosen any crusted ink. NOTE: Be careful, especially if you use isopropyl alcohol to clean your print heads: Some printers use rubber gaskets, and if you get isopropyl alcohol on the gaskets it could dry them out.
* For models where the print head is in the printer, drop 7 to 10 drops of isopropyl alcohol (91% denatured isopropyl alcohol - not 'rubbing' alcohol) down the ink receptacle area where the ink actually flows from the cartridge into the head. Run a few self-cleaning utilities. If possible, allow the printer to sit a few hours or overnight and repeat the self-cleaning utility.
* If the print head is in the cartridge, soak the cartridge print head in hot water. Allow it to soak overnight. Dry the print head area with a paper towel. Repeat the self-cleaning utility.
* If the hot water soak did not unclog the print head, place the cartridge printer head in isopropyl alcohol and allow it to soak overnight. Use a damp paper towel to wipe off the print head area and dry carefully. Try the self-cleaning utility again.
* If the alcohol soak did not unclog the print head in the cartridge you may need to purchase a new cartridge. This will provide new print heads that won't be clogged. Contact a service technician for repair of print heads in the printer if the alcohol did not unclog the printer head.

A local printer repairer near me uses isopropyl alcohol to soak the print head in, which loosens up the dried ink.
Then he has a special empty ink tank, with a hole in the top.
He connects a syringe to his custom ink tank, then squirts liquid through the head, using pressure through the syringe (a tight fit is needed).
I have also heard of soaking in hot water and cleaning them with a toothbrush. Dry them thoroughly.
Alcohol swabs use isopropyl alcohol, but you need a bit more liquid than what's on a swab.
Sometimes it's easier to hang the expense and buy a new head.
Good luck.

First you need to ensure that this is not a driver problem, by reinstalling drivers and testing the printer on a different computer.

Also ensure that ink cartridges are OK, try replacement inks.

If the problem is not a software problem, and the printer is recognised by computer, and the printout is coming as a blank or faded page, then you usually have a faulty or clogged printhead.

Try first performing print head cleaning procedure from printer tools, that may not fix the problem, but do the cleaning a couple of times, just in case.

If the print head is clogged, that can be fixed soaking the print head in isopropyl alcohol overnight.

If still no luck, then the printhead must be replaced, here is the part: Canon MULTI-PASS F-80 Print Head $61.00

buy new HP printer you will have no problem with nozzels

All the people in this forum with a Canon ink printer not printing black, especially if you tried replacing the print head and still have the same problem.

Your purge unit/capping assembly is most likely clogged. This can be caused by using crappy ink cartridges and by not using the printer for exptemely long periods of time.

You will have to disassemble the printer. First open the lid so the print head moves into the centre of travel. Unplug the power cord. Remove the upper case (can be hard to do, usually they're snap-together).

Remove one screw on either side of the print engine and remove the engine from the lower case. Unplug the cables that go from the main board to the purge unit (the large black assembly covered with old ink, located on the right side of the printer where the head usually would stop after you've finished using the printer and shut it off).

Now you have to remove that black purge unit from the right side of the engine. Usually there are two screws holding it in place.

Give the unit a bath, carefully removing old ink from everything so the unit looks like new. (be sure to remove the one motor first or you will ruin the motor). Check the bottom and make sure the two small clear rubber tubes are not clogged with old ink. Clean the absorber off (the pad in the lower case) if it has ink piled into a small hill shape.

If the tubes look like they might be clogged, you'll have to find a way to clear them out. I can do it in my shop, but it's too in depth to explain.

Reassemble the printer, connect to a PC and do a few deep cleans and print out a test page. Problem solved.

Remember, if one colour is not working it's because the head is clogged. You will have to do multiple cleans to get it to work. If it still doesn't work, then either it's REALLY clogged or the purge unit is not working because it's clogged. If you buy a new print head, then the only thing left is the purge unit. Be brave and try the disassembly and cleaning, or take it to your local service shop.

We charge $45 CDN for a job like this.

Rule of thumb: If you can get it fixed at a shop for 1/2 prince of a new unit, go for it.

Use another new genuine (original brother) BK cart. Do the cleaning twice only for BK. Wait some time (4 hours). If the ink has dryed up, the cleaning ink will break up the dryed one. Do the cleaning again. If it doesnt work, please write again.