Sharp MX5001 dumping black developer

[Steve Perks]

Hi guys.

I currently have two seperate MX-5001's dumping black developer every couple of months.
The developer ends up in the waste toner bottle.

I've done a search here and noticed a couple of threads on other models (ARM208 etc.) and scoured the Sharp UK technical bulletins and SharpSearch.

I think we could be on the right track (time will tell) as on both machines there has been contamination of the charge corona unit and grid (usually at the rear end)

We are making a point of cleaning the charge units for all colours at every call but I'm not confident we are at the root of the problem.

We are also considering swopping out the HV board in case the Dev Bias voltage is going astray.

Has anyone else experienced this issue on this specific product range?

We have also ensured the machines are level.

Any pointers would be appreciated.

Cheers

Steve

[uber]

yeah, i have had that once, will have to keep an eye on that , i just replaced the dev , it hasnt done it again tho..

[MHeon71]

Well, I have the same problem. I replaced the DV and the MC PWB, which was part of a bulletin for light copies, but never said anything about DV spilling. That has not worked and now I am in the process of replacing the DV, DV unit and black drum unit. We are ordering it today.

[OMD-227]

There is definitely no bulletin on DEV loss so far on the C-Jupiter 2's. There is a bulletin on TONER loss from the dev unit, which was fixed with a different seal & cover. On the 5000 series, it was implemented from the beginning, on the 4100 series it was released abit later. Your 5001, should have the correct dev unit.

As with any dev loss on the MX machines, I'd be looking at the drum surface. Also, make sure the grid is sitting correctly (I've seen some grids catch on the clear seal along the front of the drum - removable cover) causing faint color in that area as the grid is contaminated with toner & dev (yet not showing errors or charging) and the LSU shutter is installed properly so drum/dev are therefore sitting straight against each other (long shot... but I've seen it before).
Dont order a new HV board. Have not seen a faulty HV board cause this issue yet..... on any MX. You will get blank pages or completely over-toned pages if that was the case. Dev pull is most likely drum or dev unit related. Make sure the firmware is latest & perform 46-74 calibration afterwards.

[Steve Perks]

Thanks guys.

Wazza,

The new toner seals and cover were fitted (from April production cut-in if I remember correctly)

I think I am on the right track with the toner contamination of the charge unit/grid. (causing arcing?)

The logical question is why it is getting contaminated?
You provide some good pointers there.

The other question is why it happens on black on both of the machines?
I'm presuming it is because that is the highest volume used on both of them.

Both of these machines have exhibited the problem in the last week and have had the dev changed.

Time will tell whether they are fixed and I'll post back here when I'm happy they are.

I had my suspicions I was not alone with this issue but Sharp UK are not aware of it.

Thanks again folks!

[OMD-227]

An update on this subject.

I have just been to a call on this model, with only the yellow working. CMK had nothing on the page. No codes, no problems, machine working fine, just no CMK.
No common issues found, but I traced the fault to Black Developer dropping down onto LSU shutter solenoid & causing shutter solenoid to lose almost all power, therefore not opening the CMK shutters enough.
The shutter solenoid plunger was completely coated in black dev and inside the solenoid which should be white, was obviously black. Cleaned the solenoid out and everything works fine.
For some reason the black dev unit is dropping dev, but it is a new updated part and everything looks fine. From seeing what you guys have written on this subject, I will replace the K dev unit and go from there. Obviously checked & confirmed drum units are OK. Only done 40K, but will be replacing this as well.

Just letting you know incase someone else sees this problem (as K dev loss looks common - first time I've seen it myself on this model today).

[Steve Perks]

Many thanks for the update and info Wazza

FYI, the first time we saw this issue, we immediately changed the K dev unit as the first option (already modified for the seals). The fault has happened on that particular machine twice since then.

I haven't seen any of the two problematic machines for a couple of weeks since we thoroughly cleaned the charge units and grids, which were fairly heavily contaminated.

We are going to pull Sharps' product specialist in if we have any more problems and I will of course feed back any outcome here.

[Steve Perks]

Quick update on this issue, the latest SharpOffline file has this infomation:

F2-40 (Toner empty sensor abnormality K), after replacing dev, dev tank and PCU PWB
ADVICE There can be arcing between the drum main charge and the copier frame causing the toner and
developer to be sucked from the dev tank, this will cause the value in the developer set-up to reach
the maximum of 255.
The cause is arcing in the process electrode cover, between the rear frame and the drum/dev tank.
The parts that will need replacing are item 11 and 15 in section 46 of the C-Jupiter parts manual
PFTAP0149FCZZ - Process electrode cover
PCASZ0312FCZZ - Process electrode case

Maybe relevant and indicates we may have been on the right track with the charge arcing suspicion.

[glewisme]

I ran in to a similar issue on the 35/4501 arching except it was magenta

[OMD-227]

I spoke with field managers about this being a possible problem (process cover & case) a long time ago, but was straight out told that has nothing to do with it on the C-Jupiter 2's. It only affected the CJ1's.

I have been given two new dev seals to fit to any machine I come across with this problem, and I have to report back what happens over a period of time. From what I see, Sharp is definitely aware of this issue and is working on more mods for the dev units.