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05-20-2011, 05:26 AM
Have a Bizhub 420 that jams at the reg.roller with the rear edge of the paper scrunched up after the loop roller as if rego roller has not started and the loop roller has run on.
Not sure which clutch is at fault or if its the temp.stop sensor?
From what I have read on web sites both of these clutches play up.
I am about to order both clutches but am curious which one you think it may be.
It looks sraightforward removing this assembly though I havnt removed one before so any advice on removal of the transport unit assy would be great.


05-20-2011, 06:06 AM
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05-20-2011, 12:52 PM
It will come off the machine easy enough, although remember Konica puts their stuff together well. Lots of screws in that machine. I think the gear pack that drives the fuser is bad about breaking teeth

05-20-2011, 03:35 PM
replace the registration assembly and clutch

05-20-2011, 03:57 PM
do both clutches while you are there. saves you some time.

05-20-2011, 04:09 PM
registration assy. comes with one clutch--you will need the other one

05-20-2011, 11:54 PM
is this issue happening with single or double sided prints ?

Another common issue with these machines is the duplex unit clutches, which cause a timing issue in double sided long edge feed a4, but not in short edge feed. the paper will seem to be jamming at the rego unit - but it isnt. I'm sure everyone has seen this by now though, the early machines were terrible.

05-25-2011, 05:30 AM
Thanks guys

I replaced both clutches. Fixed the problem.
Had fun working out how to remove assy. and replugging the clutches under the dev guide but all good now.


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