Mx-C300w Black mark issue

[Bearl]

Hi guys,

I have a strange issue with a Sharp MX-C300w mutifunction machine.

Bit about me, I'm an experienced tech been swinging the screwdriver for 20 years, worked for just about every brand of copier but this one has me really stumped.

I'm getting the following black lines on the pages. On the internal test page the marks are always in the same place. The line is much worse on a colour copy. The marks are on the drum before they are on the transfer belt - I'm assuming that the line is being written to the black drum.

I've swapped drums around - the problem always stays with the black drum unit.
I've removed the transfer belt cleaning blade and cleaned - it appears to be working fine. I've also checked the pressure rollers under the transfer belt, again nothing appears out of place.
I've removed the laser unit and checked there's nothing on any of the mirrors.

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I hope someone has some ideas for me, thanks in advance!!

Cheers,
Brad

[bilyahn]

Re: Mx-C300w Black mark issue

If I read your post correctly you answered your own question. If the mark followed the black drum unit then that is the culprit. Probably the cleaning blade, what is the maintenance count on the drum?

Good luck.

Bil

[Bearl]

Re: Mx-C300w Black mark issue

If I read your post correctly you answered your own question. If the mark followed the black drum unit then that is the culprit. Probably the cleaning blade, what is the maintenance count on the drum?

Good luck.

Bil

Thanks for the reply Bill, sorry I didn't write that correctly, the problem doesnt move with the drum, i can put any color drum in the black slot and the line stays in the same position.
I wish it was that easy!!

Brad

[copiertec]

Re: Mx-C300w Black mark issue

Have you tried a different black developing unit?

[Bearl]

Re: Mx-C300w Black mark issue

Have you tried a different black developing unit?

I haven't. I have removed the dev from the mag roller where the lines are and its in good condition. There is a good consistant toner brush across the dev roller though.

[copiertec]

Re: Mx-C300w Black mark issue

I haven't. I have removed the dev from the mag roller where the lines are and its in good condition. There is a good consistant toner brush across the dev roller though.

I would try that next before you start to replace boards.

[Greg Kinloch]

Re: Mx-C300w Black mark issue

if not the drum blade or recovery blade it looks like the DV unit to me. either recovery or doc blade.

[Bearl]

Re: Mx-C300w Black mark issue

I would try that next before you start to replace boards.

Okay Thanks guys, ill have a look at the dev unit a bit more closely, ill keep you posted!

[Bearl]

Re: Mx-C300w Black mark issue

if not the drum blade or recovery blade it looks like the DV unit to me. either recovery or doc blade.

Okay i pulled the k dev unit out, popped the cover off, couldn't see any build up on the blades. The dev looks great on the mag roller, no disruptions, blemishes

When I look at the black mark on the page, after printing the nic page, where the mark is I can see the text almost like a negative print. It is not a cleaning blade as i can change drums but the problem remains....got me stuffed :/

[danceswrabbit]

Re: Mx-C300w Black mark issue

fuser?

[Bearl]

Re: Mx-C300w Black mark issue

fuser?

Nah, fuser is mint. The mark is on the the drum cylinder before it goes onto the transfer belt. Nice try through 😜😜

[copiertec]

Re: Mx-C300w Black mark issue

Okay i pulled the k dev unit out, popped the cover off, couldn't see any build up on the blades. The dev looks great on the mag roller, no disruptions, blemishes

When I look at the black mark on the page, after printing the nic page, where the mark is I can see the text almost like a negative print. It is not a cleaning blade as i can change drums but the problem remains....got me stuffed :/

Try a new developing unit, they are relatively inexpensive . In the past, I have replaced multiple developing units that looked good visually however they were bad internally. Then if you replace it and still have the issue you can go on to more expensive options such as boards.

[Greg Kinloch]

Re: Mx-C300w Black mark issue

Does it appear on the page or the drum if you run a 8 1/2 X 11 R ? (long ways). Not sure about this model as i am old school but some form of erase lamp?

[moose55]

Re: Mx-C300w Black mark issue

I concur. I would go with a DV unit. The thing that stumps me is that you say you can see the print in the line that is left on the drum? That almost leads me to think LSU. I have seen some bizzare stuff from bad LSU units in the past.

[Bearl]

Re: Mx-C300w Black mark issue

Does it appear on the page or the drum if you run a 8 1/2 X 11 R ? (long ways). Not sure about this model as i am old school but some form of erase lamp?

Hey Greg, I'm in Australia, we only run A4 here, but the orientation of the paper in this machine only goes in the A4-R direction. I was thinking blanking lamps too but as far as I can see on this model the blanking is handled by an led at the machine side of the drum which shines through the drum unit to blank the drum. Unfortunately this is where the theory fails as I can change the drum and the problem doesn't change ( since the blanking is done through the drum unit, logic would say that if there was a blanking issue the drum would change that).

Appreciate your help!