Epson 7900 from the inside - out

[Garnick]

Hi, another 4900 problem here...

After several years of perfect performance with no issues, my printhead went out all within one day, first the cyan channel, then everything but magenta and yellow, and then nothing on paper at all. I took it apart and cleaned everything. Laying the printhead on a microfiber cloth leave a rainbow of all the colors, so it appears ink is flowing. I cleaned it anyway. I didn't notice anything unusual anywhere. Put it all back together, and still nothing.

I know it sounds like the printhead, but I was assuming only individual dots or channels would go out as the printhead aged. I find it hard to believe the entire printhead died at once. Bad timing too, as I just replaced all the ink cartridges just a few months ago.

Can anyone think of anything that might cause everything to go out at once, within 24 hours? Maybe a power supply that feeds the printhead? I hate to pay big bucks for a new printhead and then find that wasn't the problem.

Thanks in advance for any advice anyone can provide.

Not sure, but I believe all of the x900 series printers use a pressurized cartridge system.  I know for sure the 79/9900 printers do.  That's the noise you here as the printer is starting up, the pressure pump introducing air into the cartridges and "squeezing" the ink bladder, therefore forcing the ink into the printhead.  If the pressure pump is defective that could cause the issue you are facing.  With no pressure "pushing" the ink it will not enter and fill the printhead properly.  Occasionally, when there's a gap in a nozzle pattern I will shut down the printer and then restart.  Sometimes this will insure that the problem cart is properly pressurized and the gap will disappear.  That procedure doesn't always work, in which case I know it's probably time for a cleaning cycle.  When you start up the printer make sure you hear the pressure pump doing its job.

Gary  


  

[Four by Six]

Thank you for the quick reply, and your help! I hear the noise at startup, but I will take it apart again and verify the ink is actually being pressurized. I think if I run the ink purge/fill utility I should be able to tell if the pump is working correctly.

[disneytoy]

I have a new 7900. I want to read all 76 pages but don't have the time. I'd like some tips on preventative maintenance.

I know about humidity and have a humidifier to try and keep in the 40% range.

I think I read that you should remove the ink cartridges weekly and give them a shake? Won't that introduce air in the system?

I haven't yet, but understand I need to clean the wiper blade. How often?

Any settings I should do to reduce ink waste? Any of the auto features I need to turn off?

I;m not a volume printer but do plan to print at least something each day.

Thanks!

Maxi

[jferrari]

I have a new 7900.

I'm confused. Did you get a 9890, 7900 or both?

[disneytoy]

Both. 7900 at our Studio, and the 9890 for my fine art work. I'm in charge of both.

[Four by Six]

Well, I ran two discharge ink cycles, as recommended by the service manual, using ServProg and the ink lines are still full of ink, so there must be a pump issue. I find it hard to believe all the colors dried up and clogged at the same time. However, there are two pumps, a "decompression pump" and a pump in the IS head unit. I was about to troubleshoot which pump it might be when the printer locked up with borderfree ink maintenance tank needs replacing. Looking at it, it is brand new, no ink on it, as I don't typically print borderless, but the digital nanny has locked up everything.

I guess at this point it could be either pump, or I guess could still be a dried ink plug in damper or head somewhere. Hopefully it is the decompression pump as it is 1/3 the cost of the IS unit. I'm not willing to gamble with either purchase yet, however.

[Garnick]

I have a new 7900. I want to read all 76 pages but don't have the time. I'd like some tips on preventative maintenance.

I know about humidity and have a humidifier to try and keep in the 40% range.

I think I read that you should remove the ink cartridges weekly and give them a shake? Won't that introduce air in the system?

I haven't yet, but understand I need to clean the wiper blade. How often?

Any settings I should do to reduce ink waste? Any of the auto features I need to turn off?

I;m not a volume printer but do plan to print at least something each day.

Thanks!

Maxi

It seems that you probably have a pretty good handle on the workings of this printer.  As far as auto settings are concerned, the only one that comes to mind at the moment would be the ANC(Auto Nozzle Check).  Before printing my first file with the 9900 I turned that "feature" off.  I always run a nozzle check before I start the day's printing routine, so I don't need an automated check that might induce a cleaning cycle for one gap in the bottom line of a nozzle pattern, something I can live with quite nicely.  Obviously my advice would be to turn ANC off, but of course that's your call.  I'm sure you are also familiar with the procedure of starting up in Service Mode/Maintenance Mode.  That's where you would gain access to the Wiper Blade and also cleaning cycles that do a better job than the ones in the standard operating mode.  One caution though -- if you do go to Service Mode, be very careful not to push any buttons that you are not familiar with.  That sort of activity could shut you down in a hurry.  If you're not familiar with Service Mode access, just ask and you shall receive.  It's also a good idea to do the black ink swap(PK-MK or MK-PK) in Service Mode.  That way you can usually avoid the automatic cleaning cycle that follows a swap in standard mode.  And if you do need to run a clean cycle you're already in Service Mode.  As far as the cartridge shake is concerned, in my opinion it's NEVER a good idea to "SHAAAAKE" a cartridge.  A gentle roll over in both directions is usually all that's needed and I never remove a cart just to agitate unless the printer has set unused for more than a week(holiday).  You will notice that as the printer is working it will normally create a gentle movement from side to side.  That movement alone is usually enough to keep the ink pigments from settling.  The wiper blade should probably be checked once every three months or so, depending on usage.  You can remove an clean with distilled water, check for any damage, and then reinstall.  One more thing -- when running cleaning cycles it's imperative that you also print a full colour image between cycles.  That way you are exercising all of the nozzles and also possibly running ink through the troubled nozzles, therefore cleaning at the same time.  I hope this is of some help.

Gary   

[disneytoy]

THANK YOU GARY!!!

Great info. In fact tonight I did the first switch from Photo to Matte BLK. I did it the standard way.

I'll look into how to do it in service more. I think you start up with 3 buttons held down?

I was going to post  a question, if it was normal with the Auto Nozzle Check on to get so many cleanings.

Second number is the ml used then the paper size.

Print   Ink (ml)Size   
1   2   16x20   CLEANING
2   1   16x4   
3   1   16x5   
4   1.9   16x16   
5   2   16x20   
6   2.3   16x20   
7   4.1   16x13   CLEANING
8   1.4   16x13   
9   2.9   16x22   
10   2.2   16x20   
11   6.9   34x36   
12   2.2   16x21   
13   2.5   16x21   
14   2   16x22   
15   2.2   16x20   
16   11.7   16x21   CLEANING - AUTO NOZZLE
17   2.3   16x21   
18   2.3   16x20   
19   2   16x20   
20   2   16x21   ABW
21   10.8   11x14       MATTE        Auto Nozzle/CLEANING
22   0.3      
23   2.5   18x24   MATTE   
24   3.1   18x24   MATTE   16% LT Black

I was logging ink usage after each print to understand my cost and what to charge my clients. I have a humidifier, but haven't used it the last couple days due to rain and 70%+ humidity. I'll go back to the humidifier soon. Also I've been printing in the morning then at night. not high volume.

RE Wiper blade, Being low volume, How often should I do the blade cleaning?

So far I'm loving this printer! I'm taking my time before I break out the expensive papers.

Thanks!~!!

[disneytoy]

Okay, I have the Service manual. I want to see how to turn off Auto Nozzle Check, How to switch from Photo to Matte Black.

Is this under Maintenance mode or Service Mode?

I've printed out both sections. Pages 74...

Is Auto Nozzle check called something else? What submenu it that under?

Thanks

[Garnick]

Okay, I have the Service manual. I want to see how to turn off Auto Nozzle Check, How to switch from Photo to Matte Black.

Is this under Maintenance mode or Service Mode?

I've printed out both sections. Pages 74...

Is Auto Nozzle check called something else? What submenu it that under?

Thanks

To turn off Auto Nozzle Check:  In Standard Mode -- Press the Right Arrow Button
                                              In "Printer Setup" press the Right Arrow Button
                                              Scroll down to Auto Nozzle Check and press the Right Arrow Button
                                              Choose OFF and then hit Enter
                                              Press the Left Arrow Button to get back to the initial display
                                              You're good to go.

Gary

[Garnick]

RE Wiper blade, Being low volume, How often should I do the blade cleaning?

So far I'm loving this printer! I'm taking my time before I break out the expensive papers.

Thanks!~!!

I'm sure about every 2 months would be quite sufficient.  Once you know how to remove the blade it's not a big deal, and of course we can help you when you want to do that.

Gary

[disneytoy]

Thanks Garry and Garnick!

I've spent a lot of research before getting the printer. I want to do everything right from the start. I won't be here complaining about Epson, because I left my printer in the garage unused for 3 months. I plan to at least get a print or two every day or so. My large 40x60 will be less frequent, but, I'll study that manual.

Thanks again

Maxi

[Four by Six]

Well, I got a new maintenance tank, so the digital nanny is not holding me back. I unmounted the decompression pump and ran it to the side of unit, and it appears to run when it is supposed to, and if I take off the tube, I can feel a slight vacuum pulled when I put my finger over the fitting, so I assume it is running correctly. Much more vacuum and the tube would probably collapse and pinch off, so the light vacuum is probably correct. I never felt any positive pressure though, and the official description of the pump is "compresssion/decompression pump". But I have only seen it run in a single direction.

I've now taken most of the printer apart down to the smallest of parts and cannot see anything wrong. I can find no signs of ink draining or having been drained in the past during cleanings or photo to matte black ink changes. Is there a drain pump in the IS unit? I don't imagine they dump all the ink with the printhead, that would take forever.

I suppose there could still be a clog somewhere in the ink supply path, but there are so many tubes and manifolds, that it would be a nightmare to clean them all and put them back together again. Also, that might explain one or two colors dropping out, but all at once?

My best guess at this point is pump in IS unit (if it has one), clogged up manifold somewhere, or a driver on the control board has failed and is not driving a pump it should be driving. However, the control board is unlikely, as there appears to be feedback mechanisms everywhere that tell the controller if something is not moving correctly. My next step is to peer further into the IS unit and see if it has a pump, and if so, figure out a way to trick it into running so I can feel for vacuum or pressure. My worry is that the longer I have everything apart in my very dry office, the more likely everything ink related is going to dry up.

Any thoughts or opinions both welcome and appreciated.

Jim

[Four by Six]

I've taken apart the IS unit. There is no separate pump, but rather they have a shaft driven off the motor that goes to a tube rolling pump. There are two sections to the roll pump. One drains the big cleaning pad, and the other the smaller cleaning pad. The small one has a gasket like the parking station. To drain ink, it raises this small cleaning pad up to the printhead, and draws a vacuum to the drain line. It appears when draining ink, everything is sucked through the printhead. I always assumed it bypassed the head during big ink operations, but that does not appear to be the case. So, if the ink isn't draining, it is still possible a head clog would prevent draining, though all heads clogging simultaneously is hard to believe. I will try to check the operation of the drain pump, to make sure the tube roll pump is still operating. I should be able to run the tubes to the side, do a ink drain operation, and see if the shaft turns and I feel vacuum with my fingertip.

[Four by Six]

I hooked the input and output of both stages of the IS unit's tube roll pump to a glass of water and it drew a great vacuum and pumped the water great, so I can rule that out, which is good as it is only replaceable as a whole unit and it is expensive. The decompression pump only has a tube at the input, and the output goes into the air inside the chassis. It draws vacuum on the input, and the open output has air pressure coming out of it.

So now both pumps appear to work, so I am back to looking for a clog, I guess.

I can see the pump try to drain the ink through the printhead, as I am running the ink drain feature with all the panels off the printer. The printhead moves into position, the small drain pad is moved up and seals against one of the dual printheads, the motor rotating the shaft that drives the pump turns on, but nothing comes out the drain tube, which I have separated from the maintenance tank.

[Four by Six]

I still wonder about the decompression pump. While I did feel an air vacuum created at the end of startup and ink dump, I never felt a positive air pressure. I don't see how the ink is going to get to the head unless there is positive pressure. But, I thought Epson's had a low ink pressure warning flag, and there is no error currently showing.

[Four by Six]

Well, I'm about ready to call the printer dead. I have ink flowing in charge and discharge utilities, both pumps seem to be working, and the printhead is squeaky clean after another soak. Still prints absolutely nothing. Not a single dot anywhere on a full page test print. It's like the print head driver went out, or perhaps the power supply to it, but both should have thrown a service code. Everything seems to be working great, but still no ink on paper.

Any last thoughts or ideas?

[Kirk at ManageColor]

Printheads go and most often a stubborn printhead problem (un-clearable after normal cleaning cycles) is not a clog but a inoperable print head. The electro-mechanics have failed and can not be recovered. From all the threads I have read and my personal experience this is the case and as the say: "resistance (to this reality) is futile."

[disneytoy]

"If you're not familiar with Service Mode access, just ask and you shall receive.  It's also a good idea to do the black ink swap(PK-MK or MK-PK) in Service Mode.  That way you can usually avoid the automatic cleaning cycle that follows a swap in standard mode.  And if you do need to run a clean cycle you're already in Service Mode.  "

Quick help. I'm trying to switch from MK to PK, I'm in Service mode and don't see it. I just looked at the manual as well, what menu/submenu is it under?

Also, what menu/submenu should I use to do a Nozzle check, before I restart into normal mode?

Thanks

Maxi

[Garnick]

Quick help. I'm trying to switch from MK to PK, I'm in Service mode and don't see it. I just looked at the manual as well, what menu/submenu is it under?

Also, what menu/submenu should I use to do a Nozzle check, before I restart into normal mode?

Thanks

Maxi

The K ink switch is not a menu item, it's a button.  On the control panel you will be familiar with the white menu buttons(up/down, right/left arrows and the OK button).  To the upper left of that combination is a button titled "Black".  In either the standard or service mode that button does the same thing, it switches between the Mk and PK.  And as mentioned several times, it's always better to do the K switch and cleaning cycles in service mode.  Just remember that you cannot run a nozzle check from the control panel in service mode.  That must be done from the printer utility program. 

Gary