My Experiences with HP9000 Printheads by Matthew Theobald

HP9000s Head Replacement

Although we have found this printer to produce a good quality print and to have been reliable, there is a question mark over the longevity of the printheads and also the high cost of replacing them. You will find, in this article, my experiences dealing with these issues and I hope you will find some inspiration for dealing with your own problems.

If you own or operate one of these printers you will be aware of the cost of replacement of the printheads and may also be aware of the relatively short life-span reported by a number of owners. Hopefully, if you read on, you will find the confidence to attempt the replacement yourself and save up to �400 per head in doing so.

When routinely printing the IQ test print to confirm that the quality of print from each head was acceptable, we noticed that the L Magenta swatch had a scratchy appearance. We were advised that this was an indication of a head that was wearing out and that it would need replacing soon.

Just in case the engineer had been mistaken we decided to give the head a physical clean using a fine cloth and some wiper fluid. Repeating this a number of times resulted in the print quality returning to its original quality.

Over 2-3 days, however, the IQ print became somewhat 'scratchy' again - although the majority of prints were of an acceptable quality the problem was particularly apparent on large regions of single colour using the light magenta.

We continued in this manner for 2-3 months with reasonable success but eventually the amount of up-time deteriorated to a level where the machine could print no more than a few feet before needing a headclean, so the decision was taken to replace the suspect printhead. The price that we were given was around �1800-�2000 for parts and labour. A maintenance engineer was arranged to attend on the Tuesday following the weekend to double-check that the head needed replacing.

In order to improve the head as much as possible before the engineer came to confirm the need for replacement we switched the printer off - this seats the printheads in a bath of ink and is recommended in order to soften any congealed ink and aid cleaning.

When Monday arrived we switched the printer back on and gave the heads a purge in anticipation of the engineer arriving the next day.

When the engineer arrived he ran the IQ test to ascertain the state of the print quality and found that all 6 heads were printing scratchily. The heads did seem to recover a little after a number of strong purges but it was not consistent and still did not produce a useable print quality.

After a significant amount of further cleaning it was decided that we would replace the Magenta and Light Magenta Head under a scheme run by HP for out of warranty machines where they agree to sort out any problem (including changing up to 2 heads) for a 1 off charge of �1000 (I’m not aware if they are still running this scheme)

When a second engineer came to change the heads he noticed that there was an air leak into the ink reservoir. Once this had been fixed and the heads cleaned a number of times, the prints being produced were of an acceptable quality and the IQ prints appeared to be improving a little each time they were printed.

We were concerned, however, that once the engineer had gone, if the heads deteriorated we would have missed our opportunity to have them replaced as part of the HP scheme. We persuaded the engineer to leave the 2 heads with us so that they could be installed as part of a follow up call and we would only have to pay for the call out and not for the parts.

Almost inevitably, the day following the engineers visit, the light magenta and magenta heads deteriorated significantly. The earliest that the engineer could return was in three days so we decided to investigate replacing the heads ourselves.

We parked the head assembly, switched off the printer and removed the plastic covers. Next the printhead assembly covers were removed to allow access to the printhead themselves. Using a sharp implement such as a knife blade or screwdriver blade, score a positional mark into the fixing plate in order to record the heads position of the head prior to removal. Using the caps supplied with the new printhead, seal off the ink flow and remove the connector for the electrical feed. Take a small socket driver and undo the screws which secure the head to the fixing plate.

We then removed the printhead from the storage packet and carefully placed onto the head fixing plate, lining it up with the marks previously made. Next connect up the ink supply tube as before and press-on the electrical connector. Replace covers and run the ink system purge routine in the maintenance menu to fill the printhead with ink and run the head alignment routines to fine tune the alignment.

This was repeated with the second printhead both of which continue to print well. All the other heads have improved with use (and regular cleaning) and are printing well.

We have since been made aware that the use of an ultrasonic cleaner can return the heads to a good condition when they have been clogged with ink.

About The Author

Matt Theobald hopes that you have found this article useful and invites you to take a look at his website http://www.exdisplay.co.uk

The author invites you to visit:
http://www.exdisplay.co.uk