A short summary of situation of ink in 7900 air-pressurising system.
I noticed some ink leak on a floor behind 7900 printer a few months ago.
I cleaned up the ink and checked the cartridges (I had an original at that time).
On right side of the printer I found no problems.
On left side of the printer all of a cartridges had some ink in the air-chamber (the bottom nozzle side of the cartridge).
It was a time to change most of them as I used them from November 2011.
I changed and old original for a new 700 ml (I have ordered 1 liter x 11 ink bottles for Epson Pro9900/7900 from Guangdong China (Mainland) via Ali-express). The only one original cartridge left in the printer was the photo-black cartridge, as I didn’t use it.
Printer was working OK. It took a while for me to notice some ink on the floor again.
A few days ago I finally took out the printer back cover and found out that the air-pump was covered in ink.
I contacted Eric. He directed me to Leptech. Leptech answered in a few days.
I contacted admin from Russian site
http://resetters.ru. He didn’t answer.
Meanwhile I cleaned up the pump and area next to it. The printer's power board is next to the air-pump. The circuit board floor of 7900 is on a angle, so ink couldn’t damage the circuit boards and leaked down away from it.
I cleaned up the plastic tubes going to and from the air-pump.
I inspected all cartridges again. No problems found on the right side. The ink in the air-chambers was found on the left side.
I used syringe (from printer head cleaning solution kit) to pump out the ink from cartridges air-chambers.
When I was sucking the ink from the original photo-black cartridge I noticed some whistling noise. The noise was coming out somewhere from the top of the cartridge plastic body. The cartridge was damaged.
I changed the photo-black to a new 700 ml Chinese one. Filled up, resetted the chip.
I installed the pump and reconnected to cables.
Switched the printer on. The error 1536 kept coming on.
Rechecked the pump and wires. Reconnected the motor cable. Error disappeared.
Printed the nozzle check page. OK.
Printed the random image. OK.
Leptech contacted me. He shortly explained the situation. He wrote: ‘It happens a lot on third party ink’.
I thought it was my only bad luck with such a situation. I do understand that Epson company doesn’t like third party ink suppliers, but in my case it was the original cartridge, that caused the problem. Not the third party one.
Thanks for the answers, some help and directions.Eric does a good job. I took a lot of notes from his blog Epson 7900 from the inside - out.
Page with photos is here (for a while):
http://vetrazi.com/Ink_in_air_system/7900_ink_problem15Jun12.php