View Single Post
  #11   Report Post  
Posted to sci.electronics.repair
Jeff Liebermann Jeff Liebermann is offline
external usenet poster
 
Posts: 4,045
Default HP LJ4000 prints very lightly near left margin.

On Tue, 10 Apr 2018 08:54:44 -0700, "David Farber"
wrote:
You said:
My guess is that you dumped some toner on
the page from the toner cartridge.


I don't know how to interpret your guess. :-)


The companies the refill toner cartridges tend to overfill the
cartridges and forget to empty the overflow bins. The result is that
a replacement cartridge will dump some toner onto the page or
mechanism. This eventually gets to the fuser roller, which melts the
toner onto the paper, rollers, gears, etc.

Here are pictures of the left side of the rollers in the fuser assembly:
http://webpages.charter.net/mrfixite...r-roller-1.jpg


The fuser sleeve is definitely burned and in need of replacement. You
can replace the sleeve yourself but make sure you smear some of the
included silicon grease under the sleeve.

http://webpages.charter.net/mrfixite...r-roller-2.jpg


The red rubber pressure roller looks just fine. There's a little
black spec of melted toner imbedded into the red roller, which is
easily removed. I can't be sure, but it looks like you have some
scratch marks on the red roller surface. These are caused by melted
toner accumulating in places that are stationary relative to the
roller, and scrape the surface. At this point, it probably won't
cause any problems, except that the grooves tend to attract and retain
loose toner that eventually melts and sticks to the surface. Spin the
red roller to be sure it's clean.

I didn't see anything that was caked on but you can definitely see that the
there are some inconsistencies in the color.of roller-1. Roller-2 looked
rather normal except there seemed to be some waviness in the way it
reflected light as I was looking at with a magnifying glass.


No clue on the waviness. I've seen that happen along with a wrinkled
roller surface. They usually go together. However, there's no
evidence of wrinkling in your photo. When it does wrinkle, it can't
be easily fixed and needs to be replaced. Note that the 4000 series
fuser rebuild kits usually include just the fuser sleeve, the red
rubber pressure roller, and some silicon grease.

I decided to swap out the fuser with another LJ4000. I also created a
"printer cleaning page" via the control panel and so far it's printing
better.


Better as in there is still toner crud on the edges? Not good enough.
Did you tear it apart and blow the loose toner out of the guts? Black
toner on black plastic is difficult to see.

My guess(tm) is your replacement fuser assembly is only a little
better condition that the one you replaced. They're not very
difficult to take apart and clean, but it does take some care and
there are a few parts that are easy to break. Learn by Destroying
perhaps?

Thanks for your reply.


Good luck.


--
Jeff Liebermann
150 Felker St #D
http://www.LearnByDestroying.com
Santa Cruz CA 95060 http://802.11junk.com
Skype: JeffLiebermann AE6KS 831-336-2558