KM BizHub 423 Refurbishing - What to inspect/clean/lubricate/replace ?

**Fritzy** · 11-29-2022, 03:11 AM

Re: KM BizHub 423 Refurbishing - What to inspect/clean/lubricate/replace ?

Thanks again for everyone's input on this. I thought I would give you an update on the work I've accomplished so far:

Fuser:

I installed new upper roller and thermistors - prints are much better now that the upper roller doesn't have worn spots, so that's a win!
@ferro10 and @allan - FYI, I did try adding a layer of Kapton tape on the old thermistor at first and ran it that way for a few weeks. I saw no issues, but ordered the new thermistors anyway for the reasons you had suggested.

Imaging Unit:

I've ordered parts to rebuild, but haven't started on this yet.

Fax:

I tried the fax settings suggested by @gift. Sending faxes is more reliable - I'd say about 75% go on the first try. Some require a second attempt. Receiving faxes is now working most of the time as well (I was experiencing about 90% failure rate previously). However, even though the faxes are received successfully, a 'protocol error' occurs after the fax prints. Haven't had a chance to try to sort that out yet.
As @copyman and others mentioned - the fax on this thing is pretty awful.

Paper feeding / Jams:

When I started working on this device, I thought it was feeding paper just fine. But I was doing most of my tests from Tray 2. I eventually noticed Tray1 would jam about every 20 pages or so. I found several similar issues reported on this forum and have checked/implemented many of the suggestions (cleaning / rollers / clutches / etc), but the issue persists. Also, thanks @Synthohol and @femaster for the information about the optical sensor in the feed assembly on the 423. I was about to try one from my donor Bizhub 36, but then I remembered your posts - that would have been wasted effort.
I'll create a new post with all the details of what I've tested and replaced along with some photos. Hopefully you will have some fresh ideas for me.

Thanks again everyone. I've been learning a lot.

**copyman** · 11-29-2022, 04:22 AM

Re: KM BizHub 423 Refurbishing - What to inspect/clean/lubricate/replace ?

Good to hear Fritzy. Thanks for the update.

Soon you will qualify to being a trained & certified CTN Technician.......

To complete certification next course is on an old color model, the C253