Bizhub 350 under toning

[Will]

Have a Bizhub 350 which keeps under toning and ruining drums. Have replaced the drum unit twice, developer unit twice, transfer roller unit twice & toner hopper assembly along firewall once. Run F8 and sets up ok between 145-155. Lasts for about 15-18k copies and under tones again. Can change developer and good for only about another 15-18k copies and is undertoned again and developer is fatigued until replaced again. Customer only uses OEM toner. Running out of idea's to isolate problem, need suggestions.

[EarthKmTech]

Re: Bizhub 350 under toning

you changed the black plastic hopper section ?

What about the toner bottle drive assembly - the metal bracket with gears and 2 solenoids. The little in the middie operates the toner bottle rotation and the big one down below operates the toner adding to the dev unit.

Other than that i think its time to try a PWB-A board.

[allan]

Re: Bizhub 350 under toning

Sound more like a voltage issue. This machines are very reliable at giving those C2557/8 codes when the TDS sensor reads over or undertoned states. But then there was a reason for getting rid of the end block connector in the newer models. The transfer roller connection that sits in the front bottom side of the door is also a bugging thing.

Do u clear the supplies life and restart before running F8. Is the density bad after replacing the dev?

The order in the manual for replacement or check is:

Check transfer contact
Check Bias contact
Change PCU
Replace PH unit
Replace HV board
Replace OACB (the mechanical control board, the one where all the clutches and sensors are plugged into.

[brent]

Re: Bizhub 350 under toning

ruining drums? like putting a line on it? have you replaced the transfer roller? ask me how I know this

brent

[Will]

Re: Bizhub 350 under toning

Sound more like a voltage issue. This machines are very reliable at giving those C2557/8 codes when the TDS sensor reads over or undertoned states. But then there was a reason for getting rid of the end block connector in the newer models. The transfer roller connection that sits in the front bottom side of the door is also a bugging thing.

Do u clear the supplies life and restart before running F8. Is the density bad after replacing the dev?

The order in the manual for replacement or check is:

Check transfer contact
Check Bias contact
Change PCU
Replace PH unit
Replace HV board
Replace OACB (the mechanical control board, the one where all the clutches and sensors are plugged into.

Yes density is ok after replacing developer for about 15-18k copies. Also have replaced gear box with solenoids that has new style reinforced
studs for gears.

[allan]

Re: Bizhub 350 under toning

If you can get your hands on the boards try to change them and check. Manually tone up the developer for testing not to waste money.

[Will]

Re: Bizhub 350 under toning

If you can get your hands on the boards try to change them and check. Manually tone up the developer for testing not to waste money.

Thanks for the input, but pretty much done most all that already. Gonna start fresh once more with drum unit, developer unit, developer,
and transfer roller. And yes the supplies counter is reset before running F8.

[brent]

Re: Bizhub 350 under toning

i had the exact same thing happen. And s new dv unit fixed it. As far as I can remember
brent