Designjet 1050C Ink Spraying

Hello.  I work for a utility company and a few of our GIS employees are having trouble with an HP Designjet 1055CM.  They use the 1055CM as a backup to an HP T7100 that has its own set of problems (mainly communication problems, not wanting to print sometimes).  Please forgive me, as I am not as familiar with these plotters as some people.  The main issue with the 1055CM is that the black ink keeps spraying in the area of the areas shown below; this has happened twice in the last few weeks.  This is the part of the printhead that comes out of the little door on the right of the unit, below the control panel.  I noticed that it doesn’t have a little sponge in it like the C, M, and Y have…is that normal?  I found your page where spare parts can be ordered, but want to verify which part would suit this issue ideally. 

Thanks for your  time and please let me know if I can provide any more info.  

The black print head cleaner does not have a foam absorber like the colors do.  Loosing ink like this is one of 2 problems.  There is a valve inside the print heads that sometimes fails and allows pressurized ink to reach the print nozzles.  To check for this condition, tell the plotter you want to “replace print heads”.  That will move the carriage to the service position and tell you to open the top cover.  Remove the black print head and look at the nozzle side (bottom).  If it is wet with ink, the print head is bad.  If it is clean, the tube system is leaking and needs to be replaced.

The tube system can be ordered from: Designjet 1050C INK TUBES

Let me know if I can be of further help.