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vlad_robas
04-07-2015, 02:44 PM
Hi,

I have retitive defect on print. It consists in small white line ( about one cm long and two mm wide). And it repets itself every 250 mm. I can't figure wich component has this diameter. Can you please trow me an ideea?

blackcat4866
04-08-2015, 12:33 AM
250mm/3.14159265 = 79.577...mm diameter or 39.788...mm radius. It sorta sounds like a drum ... or a heat roller to me.

EDIT: See page K-311 of your service manual. =^..^=

vlad_robas
04-08-2015, 07:36 AM
I had take a good look at fuser and the fixing film has that mark in it.
So I'll be ordering some part's (it is first time on this machine).

Page numbering seem's to difer.

28731

blackcat4866
04-09-2015, 12:32 AM
Use the pdf search function for 251 (mm). =^..^=

tulintron
04-22-2015, 07:10 PM
I had take a good look at fuser and the fixing film has that mark in it.
So I'll be ordering some part's (it is first time on this machine).

Page numbering seem's to difer.

28731


Fusing Belt.

・Approx 188mm pitch: Damage on the drum surface.
・Approx 251mm pitch: Damage on the fusing belt
・Approx 53mm pitch: Developer conveyance failure of developing sleeve.
・Approx 95mm pitch: Soiled second transfer roller

vlad_robas
04-28-2015, 06:22 PM
I have recived the fuser part's and replaced them. In the mean while I have got error 3508.

I have also repaced now or recently
- developer's
- transfer roller
- drum's
- filter

But I have randomly some lines. It was a blue one then red and now it remains only a black one, see the atach.
28958 Line is on front and back of page even if it is one face print and sometimes get's thicker.

I have changed drum's betwen colors with no luck. Swaped main charger, cleaned laser glass.
I had this line in the past and I did get rid of it for a while but it keep's comming back.
The only thing that is not changed are part's in the primary transfer unit and the develing units.
What are your opinions?

blackcat4866
04-28-2015, 11:22 PM
It looks to me like a primary charge line, probably for the black imaging unit. It fits your scenario in several aspects:

1) Charge lines can be thicker or thinner depending on how many consecutive pages.
2) Charge lines can appear on the backside of the image because the line is created on the primary transfer belt before, during, and after the image area intermittently. The toner on the black drum transfers to the primary transfer roller, then to the secondary transfer roller, then prints onto the backside of the paper.
3) Charge lines print edge to edge through the voids.

A simple test would be to swap the black primary charger with the cyan primary charger, then watch your line change colors. =^..^=

vlad_robas
04-29-2015, 07:49 AM
I have done more than that, I changed all the primary charging units with brand new ones. The line is still there is not as thick as is used to be and doesen't appear on the back side (maybe becouse is not as thick as is used to be). So im out of ideea's.

RAI
04-29-2015, 12:20 PM
Is the line always on the bottom? Are you printing face up always? It looks like random electronic imaging issue. Maybe try reflashing firmware. I would test face up only prints to see if line shows on the front side. Then back to only face down and see if something is being written on the belt during the paper flip. Your line looks like a laser write. I'm thinking the thickness is the residual image in the secondary transfer roller and as paper passes it disperses the image out (to a thicker blurry line). Anyway just a thought.

kalindd
04-29-2015, 04:04 PM
Is the line edge to edge?
To me it looks like you need to check the transfer belt cleaning blade.

vlad_robas
04-30-2015, 09:16 AM
Since last post I have changed on the primary transfer:
- belt and the recovery film (blade is almost new)
- replaced the roller's in the transfer unit

Afther all this the line is still there.

Then I brushed all the led bar's that are under the charging corona and the line is gone.

Print few pages and seem's ok. Afther 10-20 heavy prints 300 gsm the line is back. Print one side and it doesen't apear on back, but it is from side to side.
I'm going crazy with this machine.
I have no knowlege about updating FW on this machine.

copyking
04-30-2015, 03:01 PM
Ok, a long shot but here it goes..
Try changing the pressure between transferbelt and second transfer roll, you'll find settings for this under the tray settings somewhere ...
I remember having similar lines and solved them with this..

/Henrik

vlad_robas
05-01-2015, 04:19 PM
can u be a little more specific about where should I look for that settings?

vlad_robas
05-04-2015, 08:58 AM
I have come to the conclusion that I have to change developing unit on bk.
And I have come to that conclusion becouse I have exchanged bk and yel unit's without closing the front door and only trick the switch so that the copier will start and I have run a few pages.

tulintron
05-04-2015, 01:28 PM
I have come to the conclusion that I have to change developing unit on bk.
And I have come to that conclusion becouse I have exchanged bk and yel unit's without closing the front door and only trick the switch so that the copier will start and I have run a few pages.


Very good vlad_robas. Reversing the revealing units show in another color.


Another case that came across was with an adhesive tape located before roller 2nd transfer. When broken, shaving in the transfer belt and cause risk in print.


A03U 5239 00 HOLDING SHEET

vlad_robas
05-09-2015, 01:30 PM
In the waiting for another dev unit to put on bk I have emptyed dev unit's and switched developer inside. (bk unit is now with yellow dev in it and the same switch with the other one)
This should have moved the line with the old bk unit on yelow but it didn't.
So it isn't the dev unit.

The line somethimes dissapear only to come back later and it get's more wide if thr paper is thicker.
Useless to say that I have no clue about what to try next.

vlad_robas
05-20-2015, 05:00 PM
I have found a solution for now:
Removed all 4 glass protections between the laser and the printing units and the line is gone... I suspect that it has an airflow problem, but...
I has 2 week's now and no problem at all.

copyking
06-08-2015, 03:50 PM
can u be a little more specific about where should I look for that settings?

Hi, Glad you solved the problem, but iŽll give u an answer where to find the setting for 2nd transfer pressure.

Under "Paper settings" press "change" then "process adj" then "next" 2 times, and there are the settings for 2nd trans pressure. I have had strange lines and paper wrinkle and solved it by change 2nd transfer pressure to "Low"

(sometimes in combination with "speed down" and different values in separation DC and AC.

//Henrik

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