Spots of Black

[heyskull]

Last week I had an issue of some of one part of the black and part of the cyan went blocked and wasnt printing correctly.
I worked out that the pump wasn't pulling through, so I removed the complete station and cleaned the pump and fitted a new cap.
This seemed to cure the issue, until I came in on Saturday and the left hand black line into the head was empty of ink.
So I cleaned it again and found that the new cap was not quiet sitting right in the station, so I reset it as it was been held centrally with the lower spring.
This morning I ran a test print and due to how well I keep this machine clean the test print was perfect.
But on printing a print with a lot of black coverage this afternoon I am getting black spots as if the head is dripping.
The dampers have never been replaced on this machine as I was told by the last tech that replaced the head that "hew would only change dampers on a solvent machine if it had an issue"!
Does this sound like a damper issue as it does to me?

Cheers
SC

 

[heyskull]

Should I replace all the dampers or change out the complete maintenance station?
I have both these items on standby but the maintenance station was changed only last month.

SC

 

[GAC05]

I would change out all the dampers first. See if that solves the issue.
Take note of what they look like when you pull the covers off. Should be about half full to be working properly.
I think their regular replacement schedule is once a year.
A month old maintenance station shouldn't be failing so soon. Is it Mutoh OEM or one of the cheaper copies?
I replaced the one in my 1304 with the cheaper copy about a year ago - seems to be working ok except that ink flies everywhere when it wipes the head.

Good luck with it

wayne k
guam usa

 

[heyskull]

Wayne

I have used the copy maintenance stations twice now with no issues. I find the wiper is a bit more inflexible than the originals, this causes the ink everywhere problem.
I also add a little cleaning fluid in the cap to keep the pump clear.

Guess the dampers are the next port of call as they are now 9 years old!!!!!
Is their a diagram to show how these are replaced?

SC

 

[GAC05]

Wayne

I have used the copy maintenance stations twice now with no issues. I find the wiper is a bit more inflexible than the originals, this causes the ink everywhere problem.
I also add a little cleaning fluid in the cap to keep the pump clear.

Guess the dampers are the next port of call as they are now 9 years old!!!!!
Is their a diagram to show how these are replaced?

SC

It's pretty straight forward.
Take the covers off
Remove the bracket that holds them down.
Pop them up off the manifold
Unscrew the lines
Put the new ones in
Pull some ink thru and then seat them back on the manifold

Some notes:
Use a flat bladed screw driver to pry the damper straight up off the little nipples on the manifold. There are flats down low on the dampers to pry against.
If you pull it off center or tilt it side to side it can crack the manifold.
Make sure you change the "O" rings (mine came with the dampers) but they are sold separately if not.
When you seat the new damper put a drop or two of cleaning fluid on the "O" rings and nipples to help them slide into place without twisting.
Take extra care to keep the ink from dripping on any of the boards and ribbon cables. I think the ink can ruin both.
Final - as you are working around the head - make sure you have the printer unplugged and the capacitors discharged (pressing the power button a few times with the cord out) before you start.
Lots of posts here from people doing something on the head carriage and having one or more fuses blow.
Should be more than a few DIY videos on Youtube:
Mutoh Valuejet 1604 Damper Replacement - YouTube
If you take your time & a little care it is not hard at all.

wayne k
guam usa