Konica BH 223 283 423 fuser units having issues?

[blazebusiness]

Installed a brand new oem fuser unit from Konica and it had a flat spot on the lower roller which caused a thumping noise. Did a return RMA with Konica and they sent out another brand new fuser unit. No thumping or flat spot. But customer called back and the unit is fusing poorly/image rubs off a little. Like most tech's have seen when there is not sufficient pressure between the lower and upper rollers. I did increase fuser temp in service mode to compensate for the poor fusing but issue not completely remedied by that. Question: has anyone else been experiencing problems with brand new factory origional fixing units for these models?

The only bulletin on fuser issues I can find pertains to the fusers prematurely wearing but nothing on an issue with brand new units bad out of the box:

Description
Marks on copies/prints.
Solution
CAUSE: Upper fixing roller premature failure due to scratching of the teflon coating by the thermistor and/or fixing claws. This might be due to improper
fusing, causing toner and paper dust to adhere to the thermistor/claws.
SOLUTION:Replace the fusing unit (p/n A1UD R709 11), then increase the fixing temperature on the machine.
1. Enter Service Mode.
2. Touch [Machine] g [Fixing Temperature].
3. Select Plain Paper and change setting to 5 degrees C.
Note : The fixing claws should also be checked and cleaned at every service call.


Customers origional fuser only had an issue with a scored upper roller,no issues with fixing or noise. Certainly 2 bad fuser units in a row seems excessive----any feedback much appreciated.

[copier addict]

Installed a brand new oem fuser unit from Konica and it had a flat spot on the lower roller which caused a thumping noise. Did a return RMA with Konica and they sent out another brand new fuser unit. No thumping or flat spot. But customer called back and the unit is fusing poorly/image rubs off a little. Like most tech's have seen when there is not sufficient pressure between the lower and upper rollers. I did increase fuser temp in service mode to compensate for the poor fusing but issue not completely remedied by that. Question: has anyone else been experiencing problems with brand new factory origional fixing units for these models?

The only bulletin on fuser issues I can find pertains to the fusers prematurely wearing but nothing on an issue with brand new units bad out of the box:

Description
Marks on copies/prints.
Solution
CAUSE: Upper fixing roller premature failure due to scratching of the teflon coating by the thermistor and/or fixing claws. This might be due to improper
fusing, causing toner and paper dust to adhere to the thermistor/claws.
SOLUTION:Replace the fusing unit (p/n A1UD R709 11), then increase the fixing temperature on the machine.
1. Enter Service Mode.
2. Touch [Machine] g [Fixing Temperature].
3. Select Plain Paper and change setting to 5 degrees C.
Note : The fixing claws should also be checked and cleaned at every service call.


Customers origional fuser only had an issue with a scored upper roller,no issues with fixing or noise. Certainly 2 bad fuser units in a row seems excessive----any feedback much appreciated.

I installed a brand new OEM fuser a couple weeks ago with the same issue, not fusing properly. I slip a piece of paper between the rollers and one side had no resistance. I ended up disassembling the fuser and the one pressure lever was caught on the frame of the fuser. Once I corrected that it worked properly.

[srvctec]

No issues here yet but we rebuild more than replace with new AND the rebuilt ones last much longer because the aftermarket rollers we use are way better than stock.

[Woxner]

only had press spring pop out of place during shipment. repaired it a was a ok.

[copyman]

Agree the aftermarket UFR is much better. I only rebuild with new UFR & thermistors. The brown UFR's seem to last much longer. The OEM & some other black rollers look like they are spray painted with no teflon!

[CraigW]

Some good tips on a fix.

So sad that 200-350s would last 500k + without a mark.... these get marks and lines at 80-100k.

[copyman]

You are right Craig. Even though the black UFR rollers look the same as the older models, 200/250/350 something must have changed with 223 fusers because as you posted they crap out before 100k.

Also I have a friend that has been having issues with the fuser lamps in the 223 series. Actually he posts on this forum and may have even addressed this issue before.

I'm sure this all has to do with the OEM trying to save a few dollars by going to cheaper materials!

[blackcat4866]

On the 423's they only get manufacturers 50% of yield at best. Like clockwork. =^..^=

[allan]

If its 3de party toner it could be the problem, not enough or to much resin in there. Else if the combination of your mag brush being to thick and the dev being over-toned, the result could be similar.

They have put the thermistors onto spring brkts at the end, but its not the pressure that scratches the roller its poor thermistors. I remove the OEM ones and change them with working 3de party spares. You can rebuild those units until the fall apart. Its a 1/4 of the cost of a new one and the parts last 400K +.

[REGSIS]

I clean thermistors and separators every 20k. OEM UFR lasts around 200k.

Katun UFR (brown) lasts longer than OEM and price is 1/10 of new unit.
With one replacement, new fusing unit can easily lasts 500k.
I never replaced thermistors.