Bizhub 250/350 eating drums

[fixthecopier]

I just became aware of this problem as I was leaving the shop. The service manager has a 250 and a 350 with same problem, machines are in different locations. The 250 has 260,000 copies. The drum and developer were changed at 200,000. It lasted 42,000. Changed it and it lasted 7,000. Changed it and it lasted 7000. Dave says it is sucking developer to make copies and killing the drum. Drum charge, hv parts, and all the usual have been changed. Has anyone seen this?

[pierre]

hi there,

When you replace the drum unit,You must replace the developing unit too

[fixthecopier]

No, not on the bizhub. You change the drum and put new developer in the dv box. But anyway the whole unit was changed last tlme.

[Rudi]

I am sitting with the same problem and you are right i think the dev unit should only be replaced every 400k copies.This was never a problem on the di 2510.

[nmfaxman]

There are mylars on the dv unit that tend to warp and scratch the drum.
Trim the mylars or replace dv unit.

[ni311]

You don't have to change the dv unit, unless the mylars are broken, you're right. I usually also check the two rolls on both sides of the developing roller. At around 100k, I'm changing it. There isn't a fixed number to change these parts, depends on many factors.
Did you change the transfer roller assy?

[redhotrob]

Have you replaced the transfer roller?

[fixthecopier]

Sorry about being slack about your question. Yes the transfer was changed, and made no differance. I will get some more info today and update.

[fixthecopier]

OK, here is the fix. The DV collars are getting contaminated when the new developer is put in[ being sloppy ]. When you change the developer, be very tidy and clean up. So one of the eariler post was correct that changing the dv box should cure the problem. As this is an ongoing problem we are trying to get a part number for the collars so we can fix it ourselves. I will update.

[artfer]

DV Collars

The DI-1611 / DI-2011 DV Collars are the same as this one and have part number on the parts manual.

[wagon]

OK... I used to rebuild hundreds of di250, etc. IU's a year and since they are mostly the same as all the later stuff you will need :

1) The dev spacer rollers (at each end of the mag roller).. started in Di183. The one at the drive end wears the most, so you can often just change that one. Put a (tiny) amount of grease on the shaft before installing the rollers.

2) Inspect CAREFULLY the mylars at each end of the mag roller. They get worn and holes develop, causing dev to come out. This happens most on units with stuffed spacer rollers. If the spacer rollers are kept good you may never need to change the mylars. These, once again, are a Di183 part. You may need to glue the mylars in... I think they sometimes come with a self adhesive stuff, but I can't remember. Take care with their alignment when installing.

3) Superglue, into the dev unit casing (after cleaning), the shaft the drive gear that is driven by the machine runs on. Then lightly grease the shaft.

I apologise for not posting part numbers - I don't work on these anymore, so I am going by memory. Hopefully this will help. In actual fact, these tips apply to every model 'based on' the Di250/350 engine - so, Di350, 351, Biz350, 3510, etc.

Wagon.

[ni311]

For Bizhub 1611/2011 the part number is 4163-5298-01 and it's called ROLL

[fixthecopier]

Thanks for all of your help. I love this site.

[kingarthur]

I just became aware of this problem as I was leaving the shop. The service manager has a 250 and a 350 with same problem, machines are in different locations. The 250 has 260,000 copies. The drum and developer were changed at 200,000. It lasted 42,000. Changed it and it lasted 7,000. Changed it and it lasted 7000. Dave says it is sucking developer to make copies and killing the drum. Drum charge, hv parts, and all the usual have been changed. Has anyone seen this?

The "official" answer from Km in the uk is to tape paper over the mylars when emptying the dv units, as, apparently, when you tip over the units to empty them you are contaminating the collars. What we do is hoover out the units without tipping them up, this way the dv units seem to be lasting.

[Guest]

KM's fix: In the BH 250, I think they are now sending a plastic sheet with the new developing unit so you can cover the rollers etc. while doing the dev change.. . DO be very gentle when lifting the top cover of the d/u and flipping it over.. this is a weak spot and as questionable a design as i have seen in my 27 years in this biz.. if the cover moves more than a half an inch side to side, the control mylars just come off.. And I HAVE had this problem with a 2510 & a 3010.. I thought I'd be smart and just do a d/c in these just like in the BH250.. It tested my & the customers patience until I found out what I'd done .