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10-13-2021, 03:00 PM
Hi all

This is a code I've been getting for a couple of months, I can easily work aound it, but seeing it's looking quiet next week, I'm thinking of having a proper look, so I thought I'd ask you fine people what I am missing, before I go digging in the wrong place...

I get this code first thing in the morning on the first run. The code essentially means that the paper has entered the ADU, the solenoid has triggered to close the gate, the direction reverses, the paper passes into the conveyance path triggers PS61, but does not reach PS23. The paper stops anywhere between conveyance roller 1 and 3, it is not consistent, and you hear the motor loading, which I assume is because conveyance roller/1 is still turning, but roller/2 or roller/3 isn't. The loading is the paper jamming up as the roller/1 tries to spin, but the leading edge of the paper is stuck at the rubber rollers that are not turning. I've attached a diagram from the theory of opperation manual below which may help make sence of that.

So, this is what I have done and my thinking, so feel very free to correct me...
FYI the type of media used and size, makes no difference, and it only occures after the machine has been idle for a period of time such as overnight.

Before you all shout clutches, all the ADU clutches were replaced in the last year due to another common ADU issue, and in case you're thinking one is duff, swapping them around makes no difference.

Next you're thinking what about the motor, yes, however this motor drives a lot of the conveyance rollers, and there is no issue when simplex printing just duplex. In fact if I run 20 sheets simplex, and then 20 sheets duplex, the loading of the motor reduces, eventually the motor sound is back to normal and the press will run duplex all day, until after the next idle period.

It's as if something is getting stiff...however, I can spin the ADU drive shaft easily by hand, all the rollers appear to turn freely, all the white idler rollers appear to be free rolling and I keep them clear of crud buildup anyway. The relevant motor M41 spins up fine through the I/O function.

I do have another M41 motor, but this is a last resort because really I don't want to change that as I know it'll mean ripping the guts out the back and this machine at this age is bound to play up after a good stripping. I have also swapped the HB Motor in the ADU.

I am considering stripping off the covers, overiding the door sensor and filming the belts/clutches/rollers and see what happens when the paper passes...or doesn't...

So any thoughts most welcome...



Yes, I am an end user, but trust I don't take your expertise for granted, and always endevour to give back more than I receive.
The machine is a KM c7000, 12M clicks on the clock, regularly serviced by myself, in line with the field service manual, and only OEM parts and consumables used.
Oh and it is being mothballed at the end of the year, but I like my machines to work well!

10-13-2021, 03:19 PM
Try to replace this actuator!50382

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10-13-2021, 05:03 PM
Try to replace this actuator!50382

Στάλθηκε από το AC2003 μου χρησιμοποιώντας Tapatalk

Thanks for the suggestion, most useful, had not thought of that, and having just done it I can see why you said "try". I also changed the sensor at the same time as I was there.
Alas no change, still jamming.

I have had one thought though, what if the duplex gate solenoid is stiff could it cause enough drag to cause the jam....

Thanks again, well worth the effort.

10-13-2021, 07:51 PM
Yep typical for duplex solenoids. They quit working after sitting idle. To be honest that's my opinion based on working on office models not production. And moreover as I already know few encouraging words make wonders if the right man hears. No doubts who's the right man here Mark :)

10-14-2021, 10:14 AM
It's not the ADU gate solenoid....

If I may prove my ignorance, is there a way that I can have motor 41 running and use the I/O function to activate the clutches at the same time? Doing each part separately they check out fine, but it is in combination that the issues happen so to be able to have the motor driving the clutches and activate them one at a time would be useful, especially as I can't have the ADU pulled out and running.

The other option would be the old fashioned way, before all this digital control, strip all the rollers out, check, clean and lubricate the bearings as after 20/30 sheets the issue clears.

Anyway thanks for putting up with my random musings

10-15-2021, 03:37 PM
Quick update, I like hearing my voice anyway...you noticed too hah! ;)

I stripped the lower ADU section apart, cleaned all the brass bearings and shafts, the idler rollers second from top (conveyance/2) were particularly stiff, gundged up with years of toner dust getting into the lubricant.
Ran a duplex job, the motor still sounded like it was loading, but no where near as much, the key part being the first sheet didn't code out, which it would usually do.
So who knows, Monday morning will be the true test when it's sat idle over the weekend. Put it down to old age! The machine that is...


10-16-2021, 06:27 AM
Does it always do this?

single sided face down?
8.5x11 & 11x17
8.5x11 & 11x17

depending on what runs above, will tell you alot more where your problem is...
cleaning everything will be my first suggestion.

how many on the meter? do you have the RU installed?

10-17-2021, 01:08 AM
As in my original post, size, weight, orientation make no difference, and to add from what you said, face up face down also made no difference.

The machine is a high miler at nearly 12M which is twice what it's designed for.
The paper always gets stuck between conveyance/1 roller and 3. Which is why I stripped the lower ADU. It could be the motor (M41) getting tired and in the ADU it is driving more rollers simultaneously. I'm just chickening out from changing it, it's a lot of effort.

Yes it has the RU we have four finishing units bolted on to it, it's why we have kept it so long. It has FD509 folder/inserter/punch SD506 booklet.finisher, PB503 perfect binder, FS521 staple finisher.

Monday morning will be the test. I could remove and strip the whole ADU, when I did that a couple of years back, I was surprised what rubbish had collected under the guide plates.

Thanks for your suggestions most helpful.
Have a great weekend!

10-17-2021, 01:44 AM
Firstly, congratulations! It's a lot of work.

Just a side comment: I had a C6000 with duplex skewing. I wasn't the first or only tech working on it, and it had a lot of copies. EVERY painted adjustment screw for the duplexer had be moved/adjusted many times, and I had little hope of getting it back to its original position, but tried anyway. Fortunately for me, the paint marks mostly stayed attached to the frame, not the screwhead. Systematically, I was able to get many of the adjustments back to their original positions. Along the way, I discovered the true problem: The screws securing the alignment posts had all backed out, and posts were flopping around. So once the posts were secure, the image stabilized ... not entirely true, but consistent.

This is just a really long-winded way of saying that I hope that you have left the painted screw adjustments untouched. =^..^=

10-17-2021, 09:20 AM
yea at 12 mill i would just replace the engine on a C7000 can get them dirt cheap.
plus then you have all the parts to keep the new engine running.

Still run a C6501 every day.

2nd engine, who knows what the meter really is....

i know when TN619 toner wont be available my C6501 will keep running.

10-18-2021, 04:11 PM
Below the CDB plate is a set of gears. I replaced all of them and the ADU clutches to be satisfied. After two exchanges of M41, this solved my problem.

Manually rotating the ADU camshaft makes everything lighter. But in normal operation (with paper and speed), the defect always appeared. Intermittently, but it showed.

I only managed to sleep after changing gears and clutches.

10-18-2021, 04:30 PM
Hi Blackcat: fear not, although I am happy to have a go at most things on our presses, I am causious and there are certain things such as marked screws that I stay well away from. I start with the simple before getting into the major. Hence not taking the plunge and changing the motor.

Methgod: You are right 12M is high and it would be easy enough to swap the engine, and in fact over the last year had been on the lookout for one. But they just don't come up and prices at the moment are going up. IN the UK many presses don't come on the market they are simply bought by dealers who export them to countries like India. We would most like have upgraded to a 1070 or 2070 as they should be able to run all the finishing units too. Similar to you we have a c5501, in fact it was our first digital press, and it still runs, easier to fix and cheaper, and we have a shed load of spares and toner for it similar to you so well worth keeping. We would have preferred to have kept the c6501 we had but our one of these wasn't very reliable, so after 5M mothballed it. In fact instead of selling it I stripped it down it it's screws for fun. But I always found that the odd part I needed was always one I had not kept!! Currently in the UK I've been able to get any of the OEM toner we have needed, but know that may not last for long.

Tullintron: Will have to look at those gears. I have a spare ADU from a c6501, so will check the parts listings to see which ones are the same. I know the ADU was working fine when I took it out, so could be worth swapping the gears over and see what happens.

Cheers all most appreciated!

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