Jagged Lines on Trailing Edge HP PageWide XL 5100

[MartinShort846]

We are getting jagged lines on our HP PageWide XL 5100.  It's only on the trailing edge and its relatively random. This happens when printing to the high cap stacker and to the basket. We have replaced everything that has been suggested by HP support. Thank you in advance for any help!

[MartinShort846]

Well aren't I just a big fat liar....

Okay, so it didn't happen when I printed to the basket.  It only happens when printing to the top stacker.

[MartinShort846]

Okay, so I found something on this forum and I'll give as much credit as I can:

https://pagewideforum.com/viewtopic.php?t=15014

"by MrXL » Mon Mar 14, 2022 3:01 pm

This is a couple months old, but figure I would share my knowledge on it.
Since the Dyes on the Print Head are staggered, you get this pattern when the printer shuts down the heads abruptly to prevent printing on the belt. The cause of this is usually related to the paper not being where it's supposed to be when expected. This could mean the stacker is grabbing too fast, vac is clogged, or even dirty output sensors. I would send jobs to the basket to see if it does there. If it does, it's not outoput, and could mean dirty belts or clogged vac holes. If the pattern happens in the middle of prints, that could be an issue with the Analog encoder (loose/cracked housing, dirty encoder disc).
Outside of that, it could be an issue with page length or media advance."

I brought this to our printer guy (didn't realize he'd be here so soon).  He said that that is all correct.  Basically, at the end of the print job, the paper is going through too fast, and as a result, those staggered print heads are printing the way they are.

He said it could be a sensor.  He's checking into it.  I'll update when I know more.

[Reprotech]

Probably some thing to do with to much resistance on the Big belts.    Gear box lube dried out, bad gear box bearing, possible motor but not my experience.    Don't think intermediate roller worn out would cause this but is possible.    Take the motor out and disassemble the gear box, gears and clean test bearings.  Relube with lithium grease if required.    There is a gear box kit also if needed.    

I would start there