HP L25500 - Color falling out at about the 5' mark

[stickersmc]

Every time I print anything over 5' long, there's a color drop. It doesn't matter if it's a solid black 4x8' banner or a 6' run with VERY little print... it gets to about the 5' mark and something's dropping off, but I have no idea which color or if it's a ink cartridge fail, print head fail or something completely different. Either way, how does it last until the same spot every time?

The picture shows it printing a nice gray, then turns green at the 5' mark.

Any ideas?

 

[dypinc]

Looks like you're loosing light magenta. How old are the lc/lm printheads or how much ink has been run through them?

Other possibility is air in the lm line.

 

[Reveal1]

Not a regular visitor, but ran across this by chance. I just spent a lot of $ chasing a similar problem on my 25500. I agree w/ dypinc, you are losing ink in a print channel. Check the primer assembly - there are small rubber nipples that seat the vacuum tubes to the print head assembly. See if any are damaged or missing. This causes loss of vacuum. If you replace primer assembly (they don't sell the nipples), be sure to calibrate the primer assembly per the HP service manual. That was my issue. Also, do a print quality printout to find missing ink channel. If one head missing ink (for example M/LM , try swapping positions of two print heads to see if the problem follows the printhead or stays with same printhead position. You might replace a printhead only to find out it starves for ink at about the five-foot mark. Try cleaning the flex cable contacts using the plastic swab that came with your printer. If that doesn't work, than you may have a flex cable problem or PCA board issue.

I tried solving on my own but in the end, HP phone support walked me through the troubleshooting steps, actually pretty helpful.

 

[stickersmc]

Looks like you're loosing light magenta. How old are the lc/lm printheads or how much ink has been run through them?

Other possibility is air in the lm line.

The LM/M print heads were just replaced last year, but I know they're the most used, so that's definitely a possibility. It just took 3+ years before I replaced them the first time, so I was assuming they would last about the same length of time again, but maybe not.

As for air in the line, is there an easy fix for that? And/or instructions on how to do it somewhere?

Either way, thanks for the input!

 

[dale911]

The LM/M print heads were just replaced last year, but I know they're the most used, so that's definitely a possibility. It just took 3+ years before I replaced them the first time, so I was assuming they would last about the same length of time again, but maybe not.

As for air in the line, is there an easy fix for that? And/or instructions on how to do it somewhere?

Either way, thanks for the input!

3 years? Does this printer get much use? The heads are only rated for 1000ml of ink and you should expect failure anytime after that. I am getting between 1500 and 3500ml out of my print heads. Log onto the print server and check to see how much ink has been fired. That will tell you quite a bit. I don't think it's a head or it shouldn't start good and change. Sounds more like. Vacuum issue but maybe the head is getting overheated after printing for the amount of time that it takes to run 5 feet.

 

[Christian @ 2CT Media]

3500ml? That's nothing when we had our 25000, we got 15000-20000ml through the heads if they didn't get damaged in a head crash.

Run color band gutter to prevent premature failure of the heads to make sure you don't get drop out. Have the Ink lines been changed at all in the last 5 years? They develop leaks and cracks over time.

 

[DougWestwood]

we have an HP L25500

Hi There,

Our HP had the same problem a while back (before I worked here). Swapped all the print heads. Fixed it.

Still, since you're getting a good print at least for a while, I'm thinking printheads are OK and the print carriage tank might be clogged or misreading.
Please share any fixes!
- Doug
Vancouver

 

[tylercrum]

Had a similar issue in my a few years ago, starting running the color bars in the gutters, never had the problem again.
Edit: My issue was with the yellow dropping out, just fyi.