SOLVED: Canon MP830, new PGI-5BK and new (reman) print head - no black

[embguy]

Sometime, it takes a long time to clear the clog. Just flood the left purge pad with Windex every night. You have nothing to lose. This will not getting any worse.

But in the mean time, you can use the photo black for your printing. Select any photo paper for your normal printing. The MX830 will use the photo black instead of the pigment black.

Please scan the latest nozzle check and upload so that we can take a closer look.

 

[pourhaus]

I have been drizzling either 91% Isopropyl, or more recently a Windex/91% Isopropyl mix onto the left pad for 10 days now.

Here is a scan of no (pigment) black nozzle check:



You will see a faint image of another nozzle check - that is the reverse side of the paper. I am trying to reduce the amount I am using with this effort...

 

[Trigger 37]

pourhaus,... All of the suggestion were a good first attempt at correcting your purge problem,.. but since they did not work the problem is deeper inside the purge unit. I have helped many people fix this same problem and in fact I have an MP530 on my bench right now with the same problem. No amount of cleaning fixed it so I ordered a new purge unit from Canon and I'll put it in right away.

The problem is you have to competely disassemble the MP830 down to removing the main printer assembly from the base,... and then you still have a lot of work to do to remove the purge unit. Once you get it out the problem could be several things and some you may be able to fix. The simplist is that the black suction tube from the purge pump has come off. If the tube is off, it can never suck any ink out of the ink carts--down through the printhead to prime the head and therefore it will never EVER print any black. Another possible problem is the black tube inside the pump is out of position and therefore no vacuum and no suction. I could go on and on with problems but it all comes down to taking it apart. To get more information on how to take it apart you need one of my Repair Manuals. Send me an email and I'll tell you how to get one.

Before you do anything you need to do one more test to confirm the purge unit is bad. Since you have done all of the cleaning mentioned on all the previous notes, the large black pad where the printhead parks must be rather clean, almost white. If you didn't get it clean with all that you have done, then just add some warm water and use folded paper towels to blot the pad, over and over until you do get it almost white. Now use your control panel>printers/faxes>select MP830>preference>maintenience tab> and do a cleaning cycle on black only (or just cleaning if you don't have that option). Now open the top cover and use a flashlight to check the large pad. If there is no wet black ink on that pad, your purge unit is broken.

 

[ghwellsjr]

Two of the MP780 printers that I take care of (they are not located at my house) have a problem with the pigment black purge unit. If I flood the purge unit with Windex and do a cleaning followed by a nozzle check, the Windex remains on the purge unit pad although it does go down a little bit. I have been doing this for an hour or so a couple days a week for two or three weeks. It now takes four or five cycles to get the Windex to go down enough to see the pad. But the Windex that is left on the pad at the end of the session is still there several days later.

I have compared this behavior to my working MP760 printer. If I flood its pigment black ink pad and simply close the cover so the print head moves over to the park position and then re-open the cover, the pad is completely empty of all Windex. I guess the peristaltic pump runs during that time.

Trigger: you mentioned a couple of potential problems with the purge unit--first "that the black suction tube from the purge pump has come off" and second that "the black tube inside the pump is out of position". If either of these things happened but the tube is not itself clogged, wouldn't the Windex immediately drain away from the purge pad? I presume for your first case, that the tube has come off above the pump which seems like it would allow any Windex to disappear rapidly. The second case might take longer.

One other thing. I took one of my other printers to the location of the two bad ones and used it to prime the print heads of the others. I simply took the cartridges and print head out of a printer with clogged tubes and put it in my working printer, did a cleaning cycle and then returned the cartridges and print head to the original printer. Once the flow of ink is going, you don't need to do additional cleanings.

 

[Trigger 37]

ghwellsjr,...It's good to hear from you,.. but not so good to hear about your printer problems. As far as the purge unit, if the water stays on the pad after one cycle, there is clearly a problem with the purge unit. I know you are thinking,... why doesn't it just drain and the answer is; There are many things in the path and there is really no clear path. Just after the pad the tube is connected to a very tiny valve which has to open and close at the correct time to allow the suction from the purge pump to work,...otherwise the path is blocked. There is only one vacuum pump and first the black valve is opened and the pump suction is switched to the large black pad. Then it is switched to the color pad and that side is opened and the suction starts. The actual pump is very simple but very clever. Two tubes are wrapped around a drum and there is a round bead that presses against each tube. As the drum is turned in a full revolution the bead squeezes all of the liquid (air) out of the tube ahead of it as it rotates. This creates the vacuum or suction. If the bead is out of position there will be no suction. If this goes on for awhile, the tube gets clogged by drying ink and nothing will flow. The other problem is that the vacuum pump is driven by a tiny motor and the electrical drive current could also be bad. The two wire connector could have come off or the driver is bad or the motor is bad.

The purge unit is one of the most critical and important parts of any printer and you can see it has dozens of ways to break. It is also the most difficult to replace as it is mounted in the bottom of any printer and you have to take EVERYTHING APART TO GET AT IT AND TAKE IT OUT. The good news is that they only cost $15.60 plus $6 shipping directly from Canon. Don't EVER buy a used one. To show you just how good Canon is, there has been a bad design in the older purge unit in the iP4200, MP750, MP760, MP780, MP530, and they designed a new unit and upgraded the part number. They did not replace any in the field but if you try to order the old part number it has been obsoleted and they sell you the new part that has fixed the design error. This shows you that they are still taking care of older printers and designing and manufacturing new parts for old printers. They have also done this on many other things such as the printhead.

So if you can't get the water to drain out of the purge unit you know that something is wrong. On the test you did with the printhead, just by putting it in a different printer, fresh ink was sucked down into the head and primed it. Now it will print for about 2-3 pages and then run out of ink. At least this proves the head is still good.

I have the advantage because I have so many printers and I fix so many. I see all kinds of problems. I would say that 75% have something to do with the purge unit. Most of the printhead problems of clogs occur because of improper daily use, or something going wrong with the purge unit. If you try to do a lot of printing with no ink in the printhead because of the purge unit, it will burn out one or more nozzles, then one nozzle shorts out and that burns out the driver to that bank and all the nozzles on that bank don't print,.... and on and on it goes.

 

[ghwellsjr]

Thanks for all that info.

I will have to double check tomorrow when I will be revisiting these two printers if the dye ink purge unit is working. If it is, then that means the peristaltic pump is working but the valve under the pigment black pad is defective, correct?

Do you understand why the Windex I put on the working printer's black pigment pad will stay there as long as the print head remains in the center of the printer but if I close the cover and re-open it the Windex is all gone?

 

[Trigger 37]

ghwellsjr,... When you close the cover the entire purge unit does a WIPE CYCLE which is the same as doing a cleaning cycle but the head is moved away. The unit is basically cleaning the purge station of residual ink. It does this all the time, just like when it cycles the wiper blades to clean the bottom of the printhead of excess ink. So if you have wet ink (water, windex, etc.) on the pad, the suction pump will suck it down through the purge pump and dump it into the waste ink pads.

In my typical repair manual, I teach people how to clean (or test) their purge unit without having to take the purge unit out of the chassis. To do this the main printer chassis is removed from the base and then set on top of 2" wood blocks. Then a small glass dish is placed under the purge exit tubes. All other connections, cables , etc. must be reconnected. The printer is powered on and since all the covers and base are gone, you can see in detail just how each part of the printer works. From the PC you can execute a normal cleaning cycle and you can see the entire process of the purge unit and just how much ink is dumped. The black is always the first, followed by the colored ink. However, just as soon as the 3 colors are sucked into the pad, they create black ink, which you then see being dumped into the glass dish. You can then add water and just do a power ON/OFF cycle and the purge unit will clean the pads and dump anything that is in the pads. Of course this assumes that the purge unit is working. IF the water stays there after a cycle, you know the purge unit is clogged or broken somewhere. I have gone as far as putting a large black ink cart filled with just hot water and doing nothing but cleaning cycles to push all that hot water down through the purge pads, tubes, pump, and into the waste ink pads. This is not a problem since the water will evaporate.

Not only does this process show you how the purge unit works, you also get to see all the other parts work, since the logic board has a pretty detailed diagnostic routine it goes through for each power on cycle. If you have real ink installed, you will be amazed at just how much ink is dumped in just one normal cleaning cycle, and especially how much for a DEEP cleaning cycle. I hope this explanation helps you understand the process. If your ink pads won't drain, it is either the tubes are clogged, or the tube is off, or the pump is bad. By the way, the VALVEs that control suction from the black or color are above the ink pads, and since water or ink can not run uphill, if there is no suction the water will not leave the pads.

 

[ghwellsjr]

Wow, thanks for the additional info.

Now I see a MUCH simpler way to clean the purge unit. All I have to do is open the cover, wait until the print head moves to the center, flood both pads with Windex, hold the button down that senses when the cover is closed, wait until the print head is off to the right, release it and look to see if the pads are cleared of Windex.

I'm still wondering what it means if, when I do the above, one of the pads remains flooded with Windex and the other one is empty. It seems to me this indicates that the purge pump is working but there is a problem with either the valve or the tubing for the first unit. I still don't know if this is the case for the two troubled printers but I will know tomorrow.

Many, many thanks for sharing your wealth of knowledge.

 

[pourhaus]

Have to tip my hat to Trigger 37 - the procedure identified the problem, but possibly only because I added an extra step.

Here is a wide shot of the printer with the front tray open, lid and platen up, focusing on the purge pads:

I decided to test if the left (PGBK) purge was working using Trigger's method - clean the pad, then run a head clean to see if we get ink on the pad.

Here is the before shot of the pad - pretty clean:

Here is the after shot:

Seeing that I did have ink on the left pad, I thought - has something changed, let's run a nozzle check and see:

YES!!! Finally.

My tip - when you take the pad off to clean it (which is very tricky BTW), dab some paper towel or q-tips around in the now exposed purge tray to soak up any ink (hopefully dissolved by your cleaning efforts). I did this three times. I must have unblocked the valve or other area leading down to the purge pump.

I would add that yes, I did not see my cleaning fluid drain down all that fast during my efforts over the last two weeks.

I will now be dripping some cleaning fluid onto that left pad on a regular basis.

Thanks to all who offered advice on this.

Here is a link to the full-size photos & scans - http://picasaweb.google.com/pourhaus/MP830RepairAug2009?feat=directlink

 

[ghwellsjr]

I have spent some more time with the two problem printers and I have not gotten anywhere with them.

But I do have a question:

I removed both pads and revealed two small outlet ports in the rubber tray that holds each pad. I managed to put the blunt needle of my syringe full of Windex onto each of these four ports and pumped and sucked on each one. I thought that forcing Windex down one of them would result in Windex coming out of the other one of each pair but this did not happen. All four ports offered much resistance to my efforts. So how are they connected?

Trigger 37, how do I get one of your manuals for the MP780?