Drum or developer? Or both? TA250ci

[kyove]

Hi guys,

This morning a client call me due to a print quality problem.
So i run the usual 089 - color belt and I realized there is a problem with magenta.

I haven't disassembly the machine but I have to do so.
What do you think?

MFP doesn't sounds good on color print (black print are perfect and sounds good).
Maybe developer? Or drum?
Or a drive problem?

Thank you in advance,
Kyove

[daveh12]

Re: Drum or developer? Or both? TA250ci

The Dev Units in these machines are notoriously bad. Check the count on this part, its life is 300K (which it rarely gets to). if its anywhere around that replace it. Also clean laser glass from the adjustment menu, clean charge roller, drum issues on these machines usually cause a speckled print so check for that. when replacing any parts all calibrations etc need to be carried out like colour calibration, registration, half tone adjustment, uneven density adjustment and the AC Calibration. these will ensure the best quality prints.

[blackcat4866]

Re: Drum or developer? Or both? TA250ci

The Dev Units in these machines are notoriously bad. Check the count on this part, its life is 300K (which it rarely gets to). if its anywhere around that replace it. Also clean laser glass from the adjustment menu, clean charge roller, drum issues on these machines usually cause a speckled print so check for that. when replacing any parts all calibrations etc need to be carried out like colour calibration, registration, half tone adjustment, uneven density adjustment and the AC Calibration. these will ensure the best quality prints.

I agree with all that. It's pretty common to have rear developing seals fail, and developer dump at the rear, destroying the gears.

I would add that in the more recent incarnations of the developing units and the matching firmware, Kyocera has added a "thumping" function at the end of each print cycle to shake down toner that tends to collect in the lower developer seal. The way it works is that the coupler on each developing unit is a ratchet, and at the end of each cycle the developing motors reverse for a few rotations to make the ratchet bump, and shake down the loose toner. Customers that remember the earlier developing units and/or earlier levels of firmware will notice the change in the sound. On a few occasions it was very difficult to convince the endusers that it is entirely intentional, and no ... nothing is broken.

More recent models have begun including a vibrator motor to each developing unit to serve the same purpose. It works just like the vibrate function on your smartphone: it has an offset cam that when spun up makes the developing unit vibrate briefly.

Other common noises might come from:
1) one or more seized drum cleaning units, often caused by an incompletely closed or broken latches for the vertical feed guide B1. The waste auger drive is driven through the Guide B1 feed shaft.
2) Transfer belt cleaning unit drive jumps. The rear transfer unit rail can wear out from repeated removal/installing of the transfer belt. It's a huge job to replace that rear rail (junk the machine if that's the case).
3) A seizing developing unit can cause a growling noise. You'll have to turn each developing unit by hand to find it.
4) Rubbing noise (4) times at power On, and when awakened from sleep mode: Friction where the cams drive the laser slit glass mechanism. To test press: System Menu, V to pg 2, Adjustment & Cleaning, Laser Scan Cleaning, Execute.
5) Squealing noise, intermittently. Possibly related to J91 & J95 jams in the DF-780 finisher: Lower gray rollers in the JS-720 job separator break loose from the shaft and slide to the outer edges of the cutout in the exit assembly. The sound results from rubbing on the sides of the slot, and creates gray rubber shavings. =^..^=

[tech07]

Re: Drum or developer? Or both? TA250ci

Had something very similar in the past. It was drum both times

[kyove]

Re: Drum or developer? Or both? TA250ci

This morning I went to my client. I brought 1 new developer M and 1 new drum with me.

Removing the old drum and dev I can see a damage in bushing.
See the picture attached.

I have no idea how to repair drive unit.
What advice do you give me?
Should I junk the machine?

Thank you,
Kyove

[darry1322]

Re: Drum or developer? Or both? TA250ci

It is repairable. The drive assembly comes out from the back of the machine. There is a small pin that goes through the shaft to hold this coupler in place. First time takes about half a day to complete.

[daveh12]

Re: Drum or developer? Or both? TA250ci

as said above yes it repairable.comes out from the back. pain to remove though.

[blackcat4866]

Re: Drum or developer? Or both? TA250ci

TASKalpha 300ci light copies and prints in black only, color ok

=^..^=

[kyove]

Re: Drum or developer? Or both? TA250ci

It is repairable. The drive assembly comes out from the back of the machine. There is a small pin that goes through the shaft to hold this coupler in place. First time takes about half a day to complete.

Can you give me some indication on how disassembly the drive unit?

In Service Manual there is no reference on there parts.
Maybe someone in Kyocera thinks these are eternal!

[darry1322]

Re: Drum or developer? Or both? TA250ci

Can you give me some indication on how disassembly the drive unit?

In Service Manual there is no reference on there parts.
Maybe someone in Kyocera thinks these are eternal!

Service manual doesn't cover it. You just have to take the back cover off and start removing everything below the board assembly. The drive unit for the developer comes off as a complete unit once everything is out of the way but you literally have to take it all apart.

[blackcat4866]

Re: Drum or developer? Or both? TA250ci

I wrote a procedure, if your interested. Check back around 1900 EST. =^..^=

[blackcat4866]

Re: Drum or developer? Or both? TA250ci

Enjoy!:

[darry1322]

Re: Drum or developer? Or both? TA250ci

Enjoy!:

If you've never done this before, that's some handy information to have. Thanks for the effort.

[blackcat4866]

Re: Drum or developer? Or both? TA250ci

It's not a photographic record like some do. It just focuses on what order off, what order on, and where to route the wire harnesses (the things that I have trouble remembering). After 3 hours on a job it can be difficult to remember what you did at the beginning. =^..^=

[Geo]

Re: Drum or developer? Or both? TA250ci

Enjoy!:

Blackcat, you have a strange notion of enjoyment....