HP K850 Not printing magenta after a while

I have a K850 which will not print magenta after a while. The printer does not come up with any errors just a lack of magenta on the print outs.
The unit is using HP original Print Heads and Ink. I have run all the cleaning programs on the web interface several times. What happens is I change the print head and it works ok for a while then it will suddenly stop printing. Its not the print heads as I have tried more than one batch.
Anyone got any ideas this is getting expensive now at £15 a ph just for a days printing. The unit is out of warranty by the look of it according to the HP site and I am not keen to ring their 60p a minute phone line jsut yet :eek:.

TIA

Chris

Is it possibly sucking air into that print head which then prevents it from working?

Definately ring hp support, didn't think it was 60p a minute or do an online chat.

Ben

Ok I see out of warranty support is 60p a minute, how long has it been faulty?

Have you spoke to where you bought it from.

Ben

Its 60p for their out of warranty line! Cant get through on the online chat as it spits its dummy out at the model saying it isnt supported. I will keep looking for a decent number or something thanks.

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Originally Posted by ChrisH

I have a K850 which will not print magenta after a while. The printer does not come up with any errors just a lack of magenta on the print outs.
The unit is using HP original Print Heads and Ink. I have run all the cleaning programs on the web interface several times. What happens is I change the print head and it works ok for a while then it will suddenly stop printing. Its not the print heads as I have tried more than one batch.

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I was all ready to suggest printheads but ok that's definitely out.

Given that the K850, like most of the Officejets of that line (K550, K5400, etc..) are CIS kitted printers... What you describe is likely to be of the following:

1. The piston that pumps against the rubber bulb (bottom of cartridge) has jammed or is broken thus the positive pressure required to pump ink into the cartridge is not there.

2. There's a hole, or some other leak that is allowing air into the CIS loop between the cartridge entrance port and the actual printhead, which is again stopping ink replacing that already used and grabbing air (which is obviously easier to grab) instead.

3. There's a clog in the port that the cartridge slides into... It'd be difficult to tell if this is the issue but one give away is a whining sound that repeats again and again (this is the sound of the pump trying to pump ink to the printer)... You'd also notice a lot of ink in/around the port too as it's probably forcing some out of the cartridge

4. Last thing... You may have a duff magenta cartridge with an air lock or perhaps even full of air instead of ink... Worth trying a new cartridge.

A few things to bear in mind that might explain why you're getting the results you are:
a) the printheads contain about 4ml of ink so they won't display ink starvation immediately
b) the printers require positive ink pressure, hence the pumping system (you'll have heard the odd whining sound from time to time when you change cartridges, etc... )

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Anyone got any ideas this is getting expensive now at £15 a ph just for a days printing. The unit is out of warranty by the look of it according to the HP site and I am not keen to ring their 60p a minute phone line jsut yet :eek:.

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I hope that gives you some ideas... If you can take some pictures of the printers insides, especially close ups of the cartridge bay and printhead carriages and mail them to me I might be able to spot any potential problems... Or if you're really getting racked off you're welcome to parcelforce the bugger over and I'll see if can fix it.

Either way, by the sounds of it I'd seriously look for a new printer and K8600 is out now (or should be) so that's the next generation version.

Hope that helps.

Thanks for the detailed answer. There doesnt look to be visibly anything wrong with the printer. I have had a good look around. As you say the pipe must be blocked or something and the only ink that gets used is what comes in the print head.

I think I will request a new printer as it is that time of year that I get my begging bowl out. Thats 2 HP inkjets that have failed on my this last year though. I have a 2800 DTN that kept zapping the chips on the magenta (again!!!) catridges and rendering them useless as the read empty is all machines!

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Originally Posted by ChrisH

Thanks for the detailed answer. There doesnt look to be visibly anything wrong with the printer. I have had a good look around. As you say the pipe must be blocked or something and the only ink that gets used is what comes in the print head.

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Well, at a guess, it's unlikely to be a blockage that occurs naturally as the ink in Magenta is dyebased and hardly one prone to clogging, unlike pigment inks (which is the black in this scenario).

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I think I will request a new printer as it is that time of year that I get my begging bowl out. Thats 2 HP inkjets that have failed on my this last year though. I have a 2800 DTN that kept zapping the chips on the magenta (again!!!) catridges and rendering them useless as the read empty is all machines!

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Yeah, I know all about the curse of the Magenta with Canon printers in my case though.

Either way, if you do manage to get rid, I'd be interested in getting your dead unit to see if I can revive it.. Happy to pay postage n'all and if I figure anything out I'd be sure to let you know.

Sorry I couldn't be of more help though...

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Originally Posted by ChrisH

... at £15 a ph

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I totally forgot to ask this before but where on earth are you managing to get printheads at that price??

I get most of my stuff from Inkjet and toners. Oh and guess what the other K850 is doing the same thing now ffs!!!!!!!!!!!!:mad::mad::mad::mad:

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Originally Posted by ChrisH

I get most of my stuff from Inkjet and toners. Oh and guess what the other K850 is doing the same thing now ffs!!!!!!!!!!!!:mad::mad::mad::mad:

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Ok.. on the printheads thing I just had a word with IJT and they're offering me the heads for double the £15 you quoted so I'm guessing you're thinking of the cartridge prices there ;)


As to the problem you're describing a clog issue and if I was a betting man I'd say you've got a bad mix of inks or a non-standard cartridge that is screwing things up.

I've got some kit that might help resolve the problem if you want to go that route but right now the primary question I gotta ask is whether these are OEM HP cartridges or some variation of 3rd party jobs?

Oh b*gger... it seems some of my information has been incorrect so I need to do a quick redirect here:

1. The K850 uses the HP10/11 printheads, not the HP88 set... I found my error when I looked at the specification in more detail following a post I found that indicated the printheads numbered four, not two.

2. This would explain the cost of the printheads, etc... so apologies for any confusion there.


All of this aside the possible causes still stand... You're very likely to be getting a bad mix of inks.

In all honesty my advice would be (if you can) to consider these printers at end of life and go with purchase of either a K8600dn or start looking at A3 lasers as an alternative.

I've got an HP A3 Business Inkjet (can't remember the model, but know uses the 10/11 carts and print heads) which has just started doing this, but with cyan. It started shortly after the bursar fed it with a cheap fake cartridge, co-incidentally, from IJT (I believe).

It has since knackered another two print heads, even after changing back to HP inks. With this one, they don't completely stop working, but get to the point that only a handful of nozzles work. The sod is, the print heads don't work in any other printer afterwards either.

God, I hate fake ink!

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Originally Posted by crc-ict

I've got an HP A3 Business Inkjet (can't remember the model, but know uses the 10/11 carts and print heads) which has just started doing this, but with cyan. It started shortly after the bursar fed it with a cheap fake cartridge, co-incidentally, from IJT (I believe).

It has since knackered another two print heads, even after changing back to HP inks. With this one, they don't completely stop working, but get to the point that only a handful of nozzles work. The sod is, the print heads don't work in any other printer afterwards either.

God, I hate fake ink!

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Probably time for me to give a little lesson in inks...

Each ink manufacturer has a different chemical make-up with a lot of brands even in the 3rd party world and lots of confusion throughout.

First off, the "universal ink" refills are evil, poison and frankly you need your head testing if you go there. Just consider that Epson uses a piezo electric "cold" process to jet the ink while Canon and HP use a bubblejet approach which boils the ink in a hot process. The chemical properties required to make these work are worlds apart so it's something of a no brainer when you go there.

What crops up time and again in the refilling/CIS world is where people have a supplier that has chopped and changed ink manufacturers and not told anyone, plus never actually done any testing. Invariably this leads to chemical incompatibilities or actually chemical reactions... and where you get chemical reactions you get clogging, head damage and failure...

At a guess, this is what's happened here so here's some free advice for you..

1. If you're going to use a re-manufactured or 3rd party cartridge set make sure you stay with them throughout.
   
2. Check in advance that they have the same ink supplier and that any changes will be notified in advance (Oh and don't just trust them on this.. ask around to see if they are consistent). As a rule of thumb if the source is Chinese, walk away, most Chinese ink manufacturers use cheap, sh*t ink that destroys printers at worst and just doesn't have the right colour profile properties at best.
   
3. If you do change inks, flush the system (see below).

Right now that the lecture is over here's some suggestions on how to proceed to resolve your particular problem as it does indeed look like the ink itself has reacted or is reacting with either the printhead ink or has clogged in the printers internal CIS system.

1. Decide on a new cartridge supplier after checking out pricing, quality, reputation and by asking about consistency in their inks. (I can help if you want some ideas). Possibly even consider a CIS (again I can help here too)

2. Get yourself:

• a blunt needle and syringe...
  http://cgi.ebay.co.uk/ws/eBayISAPI.d...MESE:IT&ih=014
  (FYI: That's my own listing but by all means look around for other options)
• some new printheads (you're most likely going to need these - sorry).

Now follow the procedure below

• Install a new print cartridge (one from your new supplier) into the appropriate cartridge slot
• Open up the printer and get the printhead carriage into the replacement position.
• Remove the relevant printhead
• Use your syringe and needle to gently push into the rubber receptacle that the printhead plugs into normally. Don't push all the way down to the end or you'll block the end of the syringe against the bottom of the receptacle. If you do, pull back 1mm or so.
• Draw back, slowly and carefully on the syringe plunger
  
  • If you feel a vacuum style resistance then you may have a clog and may need to pull harder to draw it through. If it won't give you have bigger problems (see "clogs" below)
  • If there is little or no resistance gently pull back to pull out the old ink and replace it with new ink from the new cartridge supply.
  
  Note: To a certain extent you will need to guestimate just how much ink to draw through but as a rule I'd expect to pull at least 10ml to clean through most of the system.
• Dispose of this polluted ink appropriately.

Clogs:
If you find that you can't pull the syringe back and draw ink through the system it's possible you have a major clog issue. If so, report back and I'll try to develop an approach to solve it.


Once you feel confident that you've purged the contaminated ink from the system you can install a printhead back into the system and try again. Initially I'd advise trying one of the "dead" heads and running a series of printhead cleaning routines to clean the system further. This will indicate if the head is recoverable or allow the "dead" head to take the brunt of any lingering rubbish. When you're happy put a new print head in the system

Finally... Pray.




In all honesty you can expect to use up at least one cartridge using this approach and quite possibly clog up one more head before you get a clean bill of health again. Speaking for myself I'd be pulling a good 50 - 100ml of ink through using a CIS kit because you're not tossing cartridges, just ink (which is a whole lot cheaper!). Admittedly I build the kits though so it's a no brainer for me... :)

If you want anymore assistance on this feel free to PM me and I'll try and walk you through.

Hope that helps some more.

Thanks for that, very illuminating...

Needless to say, I have strongly recommended that fake inks are no longer used!

Unfortunately, it's already been swapped back to an HP cartridge, so goodness knows what reactions are going on in there now!

I'll have a try to get it sorted tomorrow and feedback.

Cheers!

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Originally Posted by crc-ict

Thanks for that, very illuminating...

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No problem... Nice to find that 3 years of hair pulling is useful :)

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Needless to say, I have strongly recommended that fake inks are no longer used!

Unfortunately, it's already been swapped back to an HP cartridge, so goodness knows what reactions are going on in there now!

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Well actually you shouldn't be too badly off if you've swapped back (as you're not introducing a new ink, just the original one so it can't be any worse than before)... That said, it'll take a while for the jets to clear and frankly you need the system to purge the fake junk so the other option is to print loads of Cyan (in your case) and exercise the hell out of the printhead... It's a lot like taking someone who's eaten too many fry ups and forcing them to the gym for month... You either kill them or you clear out their arteries ;)

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I'll have a try to get it sorted tomorrow and feedback.

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Np... good luck.. :)