C350 - White powder on Magenta LPH

Collapse
X
 
  • Time
  • Show
Clear All
new posts
  • grcmptrnrd
    • Apr 2025

    #1

    C350 - White powder on Magenta LPH

    Hi,

    I have a Konica BizHub C350. All imaging units were replaced about 2 months, 3,000 pages ago, genuine Konica.

    Color copies have been getting progressively worse, missing magenta streaks.


    Printed gradation test patterns for all 4 colors. CYK were fine, M has streaks.

    Removed M IU, looks fine. No scratches, no excessive toner.

    Look in at LPH and find it's covered solid in a white powder. It doesn't look like paper dust, a bit grainier.

    Check LPH for other colors, all appear normal.

    Vacuum out powder, clean with jig & alcohol, then dry pad on jig, reassemble.

    Stabilize, print gradation pattern, and the streaks are back.

    Remove M IU again, white powder is back as thick as it was the first time!

    Clean again, check underside of IU. A very small bit of white powder on casing, a few bits on drum, but not much. Vacuum off without touching drum.

    Repeat LPH cleaning, stabilize, gradation print, streaks back.

    Repeat.......


    I have no idea what this powder is or where it's coming from. Has anyone run across this before?

    I'm thinking my next step is to replace the IU, but that's an expensive test. Unfortunately I don't have the old one anymore.

    I've been running Precision Roller's USA-made aftermarket toner for a couple of years and never had a problem. Is it possible that I have a bad batch of toner?

    Any advice is greatly appreciated!
  • PeterG
    Trusted Tech

    100+ Posts
    • Jul 2008
    • 177

    #2
    Re: C350 - White powder on Magenta LPH

    My name is Tony Montana, say hello to my little friend!

    On a serious note, it would have to be paper dust wouldn't it?

    Comment

    • methogod
      Senior Tech

      Site Contributor
      500+ Posts
      • Dec 2008
      • 915

      #3
      Re: C350 - White powder on Magenta LPH

      look inside the magenta toner cartridge see if you have a bad toner...

      otherwise could be plastic shavings from something. picture of the white powder

      Comment

      • bigwul
        Technician

        50+ Posts
        • Jun 2014
        • 60

        #4
        Re: C350 - White powder on Magenta LPH

        Originally posted by PeterG
        My name is Tony Montana, say hello to my little friend!

        On a serious note, it would have to be paper dust wouldn't it?
        I guess a Toner Cartridge would be a good place for a concealment!!!......the 'white powder' might be more valuable than the toner!!!....

        This problem is not to be sniffed at.!!

        Comment

        • allan
          RTFM!!

          5,000+ Posts
          • Apr 2010
          • 5459

          #5
          Re: C350 - White powder on Magenta LPH

          Originally posted by bigwul
          I guess a Toner Cartridge would be a good place for a concealment!!!......the 'white powder' might be more valuable than the toner!!!....

          This problem is not to be sniffed at.!!

          Thats funny.

          But seriously take a photo! I am intrigued by the mysterious white stuff.
          Whatever

          Comment

          • methogod
            Senior Tech

            Site Contributor
            500+ Posts
            • Dec 2008
            • 915

            #6
            Re: C350 - White powder on Magenta LPH

            second.... all in favor?

            Comment

            • grcmptrnrd

              #7
              Re: C350 - White powder on Magenta LPH

              I apologize for disappearing after posting my question--snow days & trying to catch up has put the copier as a low priority.

              The toner, both still in the cartridge and in the hopper, looks normal.

              I did get a photo today. The coating really is as white & opaque as it appears in the photo. It has run ~300 copies since the last cleaning that left no white powder, not on the lens or anywhere around it. At least it vacuums very easily unlike toner.

              For comparison, the yellow LPH has not been cleaned since the imaging unit was replaced. While there is quite a bit of yellow everywhere, the lens remains a clear as it was after cleaning. Same for C & K, not visible in photo.

              DSC_0271.jpg

              Comment

              Working...