Need Help Printhead Clogging HP L25500

Emerald Vinyl

New Member
Help!

I finally managed to get my printer up and running (it use to have severe horizontal banding), but I purchased a new printhead... Issue fixed! The issue I am now having is it won't stay "unclogged". Every morning, I wake the machine up, run a print head cleaning, and it's clogged again. Its to the point where I remove the printhead, sit it in an alcohol bath, push air through the top ports and it works! Who wants to do that every morning though? Is there anything else I can do? Printhead cleaner kits are rare finds, and at the rate I am going Im going to need a new kit soon. Help!

P.S. Its my YK printhead only.
 

balstestrat

Problem Solver
What ink are you using HP or aftermarket? Are these HP genuine heads or some chinese?
And I hope you are not actually pushing air trough the top ports or you might have already broken the head. It only takes a small small amount of air at very low pressure.
 
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im thinking its not ur printhead...
as you say it fixed with new printhead...
nope...im sure it 'fixed' because new printhead had ink in it...
pushing air into head can burst the filter inside it

i think you have an ink supply issue to the head...
like as if the lines are clogged or an 'o' ring has failed somewhere...
 

gelink

ink jet specialist since 30 years in France
im thinking its not ur printhead...
as you say it fixed with new printhead...
nope...im sure it 'fixed' because new printhead had ink in it...
pushing air into head can burst the filter inside it

i think you have an ink supply issue to the head...
like as if the lines are clogged or an 'o' ring has failed somewhere...
 

rassym

New Member
Check the primer assembly. Its probably missing the rubber stoppers, not allowing the printheads to properly prime. Sometimes it just affects one head instead of all of them.
 

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rassym

New Member
Check the primer assembly. Its probably missing the rubber stoppers, not allowing the printheads to properly prime. Sometimes it just affects one head instead of all of them.

Just replace if any are missing, should be about $100.
 

Reveal1

Member
Check the primer assembly. Its probably missing the rubber stoppers, not allowing the printheads to properly prime. Sometimes it just affects one head instead of all of them.
It's been several years, but we once had an HP tech spend a week throwing parts at our 25500 and this was the eventual culprit. He left after replacing and we started having problems again; turns out the caps need to be aligned to the priming tubes (may be wrong term so check your manual) which we were able to do as outlined in the service manual. I think this is why HP no longer sells service manuals; they don't want to lose revenue as most of the maintenance tasks are not really all that difficult if you have the manual.
 

balstestrat

Problem Solver
Just saying that it can be the primer but it's very very unlikely that if you have the head open and in good condition that it would not be open again next day because of one priming not done successfully...
 

MachServTech

New Member
Just saying that it can be the primer but it's very very unlikely that if you have the head open and in good condition that it would not be open again next day because of one priming not done successfully...
That's not my experience. The primer does cause this issue because it actually de-primes the head when it doesn't seat properly. also, the priming assembly is a pain in the *** to replace.
 

balstestrat

Problem Solver
That's not my experience. The primer does cause this issue because it actually deprimes the head when it doesn't seat properly.
"deprimes" what do you mean by that?

Only thing the primer does is empty the printhead -> pushes most of the ink out through the nozzles and refills the head after that (and it doesn't use the primer to fill it).
If the primer doesn't have a good contact it simply does nothing. The printhead just stays full. It doesn't even use the priming unless it's doing a cleaning operation.
 

balstestrat

Problem Solver
It will clean throuout a print job and can deprime the head...at least thats my understanding.
It will never use the primer while printing. Only might use it during the cleaning in the beginning.

The priming wastes a lot of ink, it's not used if not necessary.
 

Bruce Mello

Many years in the Production Business
Replace printer with a high end printer that uses Piezo heads.
Colorpainter M64 is the best along with the rest of the Mimaki lineup.
 
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