ES456 poor copy quality, bands and light streaks front to back of the machine on LTR

[Desert Rat]

This customer called in for thumping noise and poor quality. Here's what I've done,
Replaced the drum and blade, (OEM), replaced the missing rear drum bushing.
Replace a worn belt on the back of the developer unit. None of these fixed the quality
or the thumping noise.
We pulled the main drive and clean the gears and tightened the belt. Then the noise
stopped but the quality is what you see. They have two of these machines so I swapped
the drum and developers and the problem follows the bad drum and developer.
So I swapped the drums and at one point the quality was good on both machines.
Not good enough I need to know what the problem is and now I've got myself confused.
The developer count in the original machine is 300K plus. I know it needs to be changed.
But is that enough to cause this problem? I included a sample of the copy.
I need a lesson on this model. Anybody up for that?
Has anyone had a problem with the connector in the cover that holds the drum and developer
together? Pretty flimsy in my opinion.
Any suggestion welcome.

Thanks

DR

[Desert Rat]

Re: ES456 poor copy quality, bands and light streaks front to back of the machine on

ES456 001.jpgES456Skyshot 001.jpg

[Desert Rat]

Re: ES456 poor copy quality, bands and light streaks front to back of the machine on

So on the samples, the one labeled sky shot is just that with paper over about 3 inches of the lead edge.
I can feel developer on the dark bands.

The test target sample looks like crap and developer can be felt on the page also.

If anyone has a clue, please clue me in.

Thanks

DR

[didi2005]

Re: ES456 poor copy quality, bands and light streaks front to back of the machine on

Seems like charging issue...

If swap process unit can solve the problem, then drum side need to check main charger, developer side need to check magnetic roller, gears...

[Desert Rat]

Re: ES456 poor copy quality, bands and light streaks front to back of the machine on

didi2005
I have already checked those items. And they seem ok. I cleaned the gears on the back of the developer station and the mag roller
looks ok. The erase lamps come on bright. When I swapped the units last night the problem follows the drum and developer, but it is not
as bad in the other machine.
I'm going to order some developer. I know it has been in there for twice its rated life.

Usually I can clean these chargers fairly good. What experiences have others had
regarding these chargers?

Thanks

DR

[blackcat4866]

Re: ES456 poor copy quality, bands and light streaks front to back of the machine on

Have you looked at the transfer roller? If the gear and/or spacers are incorrectly installed you'll get this exact effect. What interval in mm? =^..^=
image.jpg

[Desert Rat]

Re: ES456 poor copy quality, bands and light streaks front to back of the machine on

Blackcat,
The spacing varies. And the bands are not in the same place from page to page. I swapped the whole IU with another machine. The original machine with the problem
now make a decent print. The other machine also makes a decent print, but I can still see in half tones a light band.
I'm not going to sell any more of these machines. To flimsy, to particular.

Thanks for the watching

DR

[blackcat4866]

Re: ES456 poor copy quality, bands and light streaks front to back of the machine on

Between that and eating hard drives, there isn't much to recommend these boxes. They also shear off the drive roll pin for the drum drive. =^..^=

[lazymangr]

Re: ES456 poor copy quality, bands and light streaks front to back of the machine on

the noise and that crap copy is a developer thingy if its not on the main drive broken pin. you replaced the belt on the developer but you didnt change the 2 gears that hold the belt on the developer. check the other gears also and while you remove the platen that holds the gear dont forget to tune correctly the doctor blade. they have the problem giving noise. i am 100% sure about that.

[Desert Rat]

Re: ES456 poor copy quality, bands and light streaks front to back of the machine on

lazymangr,
When the developer station belt was changed I cleaned and inspected the gears. Used air to blow out the
the dust and stuff from the old belt. Check and adjust the doctor blade by measuring the gap in the front and making
the rear gap the same. The noise went away after cleaning the main drive and tightening the belt a shade.
Only the crappy copy remains if I put it back in the original machine.
Right now I swapped the IU unit with their other machine. This produced a decent copy on both machines
but I know this will come back to bite me. And the problem can still be seen on the other machine in the
half tone area's but not in the line print and it is not pulling developer mix out of the unit.
I know the developer mix counter reads 300K, twice the rated. Would that cause the problem?

Thanks

DR

[blackcat4866]

Re: ES456 poor copy quality, bands and light streaks front to back of the machine on

Probably not developer alone, but something to do with the developer drive. =^..^=

[copyguy69]

Re: ES456 poor copy quality, bands and light streaks front to back of the machine on

Check the wall joint in the developing unit part #6LH53440000 on page 28 of the parts manual. It is the square looking roller in front of the mag. roller. I had one where the little white bushings that hold it in were missing causing all sorts of quality problems. I replaced the bushings and machine runs fine now. I definitely think the problem is in the developer unit. Good luck

copyguy69

[Desert Rat]

Re: ES456 poor copy quality, bands and light streaks front to back of the machine on

Blackcat & copyguy,
Thank you for your insight. I may have some time today to go and check these things.

thanks again

DR

[Desert Rat]

Re: ES456 poor copy quality, bands and light streaks front to back of the machine on

copyguy69,
I'm here in front of the machine now. I put the process units back into the machines they came from.
The problem did not go away by itself. (rats)
I found a couple pieces of lint in the dv mix. Probably not big enough to cause this problem. I double checked
the doctor blade gap. I had it to big in the back. It the other machine it piled up the dv mix and left a black
band around the drum that will not come off with a simple wipe. I need to replace the drum and blade again.
Only 51K on both. I had just replaced them in the last 10 days.
I removed the dv mix, toner sensor and the board to vacuum the station. I think I will used some canned air
to give it a quick blow out.
That square looking roller is not in this unit, I have a round roller and the bushings are fine.
I am just about to fill it with developer, but first I am going to pick up another drum and blade.
Aftermarket this time just like the other unit here.

DR

[Desert Rat]

Re: ES456 poor copy quality, bands and light streaks front to back of the machine on

Blackcat, I did double check the transfer roller installation and it appears to be in correctly.
Springs in the holes for contact and it seated correctly.
Time for a parts run.

DR