Ricoh 2075 Heavy background or Negative Copy

[scenicmike]

Hi to all!
I have the following problem. The machine is a Ricoh 2075.
Everything is clean and I've tried to change drum, developer module, charge corona, transfer assy, with no result.
Heavy background or Negative copy.jpgAny ideas?

[Phil B.]

did you reset the bias for the new drum? reset dev bias?

have you tried starving the developer by doing sky shots and then re-tone the developer?

[slimslob]

This used to be a problem with early plain paper machines. Not all manufactures used the same charge polarity on their toners. My guess is that you are not using Genuine Ricoh toner, developer and drum. Either that or the HV power pack is bad or connected incorrectly.

[slimslob]

did you reset the bias for the new drum? reset dev bias?

have you tried starving the developer by doing sky shots and then re-tone the developer?

If it is a bias reversal problem, sky shot will come out blank. Checker flag is better for depleting toner.

[Phil B.]

If it is a bias reversal problem, sky shot will come out blank. Checker flag is better for depleting toner.

wow learn something new everyday... never had "blank" skyshots

[KenB]

This used to be a problem with early plain paper machines. Not all manufactures used the same charge polarity on their toners. My guess is that you are not using Genuine Ricoh toner, developer and drum. Either that or the HV power pack is bad or connected incorrectly.

I agree.

It's been many years, but I can remember several calls for this very problem that turned out to be bogus "competitive" toner.

[scenicmike]

This used to be a problem with early plain paper machines. Not all manufacturers used the same charge polarity on their toners. My guess is that you are not using Genuine Ricoh toner, developer and drum. Either that or the HV power pack is bad or connected incorrectly.

All parts are genuine! Toner and developer. Only the drum is a Katun Performance. And after the problem, the machine is vacuumed and everything is clean.
I 'm in a dead end!

[scenicmike]

If it is a bias reversal problem, sky shot will come out blank. Checker flag is better for depleting toner.

I don't know if anyone notices that there are no border deletions. And sky shot is completely black!

[slimslob]

All parts are genuine! Toner and developer. Only the drum is a Katun Performance. And after the problem, the machine is vacuumed and everything is clean.
I 'm in a dead end!

Then your only other source the the Katun drum does not have the correct coating.

I don't know if anyone notices that there are no border deletions. And sky shot is completely black!

Anytime you have a background problem there are no borders, i.e. if other white areas have background, so will the borders.

[Lagonda]

Check the bias contact and the drum earth. If it still has a problem put the old drum back in and see what happens.