Problem With Gestetner MP7500/8000

[mgi2003]

Hello to everyone. I have many machines Gestetner MP7500/8000 and i have to all the same problem. The machines does not keep the copy. I change developer and after 20.000 photocopies the machine is lost the black. i change corona,grid,drum and the machine is continiou to not have thw black. Can any one they now why ? or something to see ?

[slimslob]

Re: Problem With Gestetner MP7500/8000

I have seen number of posts for this same problem.

Did you use the correct developer? Genuine Ricoh part Number B0649640 or B0649645. Both part number are valid but only one may be available, depending on what region you are in.

Are you using the correct toner? Should be genuine Ricoh and the recipe number on the toner bottle should match the recipe number on the developer bag. If you have been using after market toner, you need to thoroughly remove all toner from the toner supply system, including the toner recycle system.

Clean the ID sensor with an only clean cloth or paper towel moistened with water to prevent creating a static charge on the surface that will immediately attract toner. If you have used alcohol or any other solvent to clean it, replace it as solvents can fog the surface.

If you did not replace the filters on the development unit and PCU, the PCU cleaning blade and PCU cleaning brush, do so now.

[Timmytronic]

Re: Problem With Gestetner MP7500/8000

Hi

This has been a problem on my machines many moons ago but if you switch of auto process and adjust the ID sensor bias so it makes a lighter ID patch it will keep the black. Check the VSG and VSP, VSG should always be around 4.00v and once the machine has settled with a nice black VSP should be at around 0.40 not 0.06 as it can be after a dev change under auto process control. Not all machines are the same but I have found a few. Also when changing the dev, leave it for 10 minutes before initialising the TD sensor switched off, front door open ready to switch back on.

I have had the boas down to 100 before but 250 is the norm for the patch. You can also lower the Charge ID bias a little but dont raise the Charge printing bias as this can damage the drum eventually and causes headaches for people near the machine due to raised ozone.

Hope that helps and follows Slims advice first to make sure thats all covered, as I said not all machine need this tweak.

[mgi2003]

Re: Problem With Gestetner MP7500/8000

I have seen number of posts for this same problem.

Did you use the correct developer? Genuine Ricoh part Number B0649640 or B0649645. Both part number are valid but only one may be available, depending on what region you are in.

Are you using the correct toner? Should be genuine Ricoh and the recipe number on the toner bottle should match the recipe number on the developer bag. If you have been using after market toner, you need to thoroughly remove all toner from the toner supply system, including the toner recycle system.

Clean the ID sensor with an only clean cloth or paper towel moistened with water to prevent creating a static charge on the surface that will immediately attract toner. If you have used alcohol or any other solvent to clean it, replace it as solvents can fog the surface.

If you did not replace the filters on the development unit and PCU, the PCU cleaning blade and PCU cleaning brush, do so now.

I use the correct developer and toner the original. i am not use after market because i have many problems before year and the machine is stack all. i see to clean the id .All the filter is cleaned

[mgi2003]

Re: Problem With Gestetner MP7500/8000

Hi

This has been a problem on my machines many moons ago but if you switch of auto process and adjust the ID sensor bias so it makes a lighter ID patch it will keep the black. Check the VSG and VSP, VSG should always be around 4.00v and once the machine has settled with a nice black VSP should be at around 0.40 not 0.06 as it can be after a dev change under auto process control. Not all machines are the same but I have found a few. Also when changing the dev, leave it for 10 minutes before initialising the TD sensor switched off, front door open ready to switch back on.

I have had the boas down to 100 before but 250 is the norm for the patch. You can also lower the Charge ID bias a little but dont raise the Charge printing bias as this can damage the drum eventually and causes headaches for people near the machine due to raised ozone.

Hope that helps and follows Slims advice first to make sure thats all covered, as I said not all machine need this tweak.

thanks for answer. i see how to change the auto process off and how to change the vsg and vsp. the bias i change it a little down. Do you remember the programs ?

[mgi2003]

Re: Problem With Gestetner MP7500/8000

Hello again i see everything of all and i find that if i have the autopreocess open when i print 500 copies the machine is black but after the work about 4 hours i have but copy it not be black. it is possible to have problems with original toner and original developer ?