MX-M350N Intermittent Jamming while duplex copying

[Arkynsaw]

Jams on duplex only , single side pages are feeding fine as per customer . Tried running a single 2-sided page through the ADF as a duplex page output , hoping to see a single duplex page jam , ran about 20 of these , never jammed . Running 8 1/2 x 11 side feed , page count is 1,125,813 , duplex model number is AR-DU4 . Ran stacks of varying sizes , reported jamming occurred twice , but of course paper stopped in 4 spots on one of the jams and in 2 spots the other time . In both cases there was a page , 2nd side with about 30 to 40 percent of the image on it , other side fully fused , the partial page had arrived at the fuser , but did not feed in , as only maybe 10 mm was fused , as it had only touched the fuser , in one of the cases it was folded , registration looked normal . other page was on the outer path of the duplex unit , feeding downward , both had this paper left after jam . And in the one case paper was in the unit on top where the page feeds out and then pulls back in . Ran a 22-6 report , jam codes indicated were mostly APPD1_S (17 of 20) , not sure if these were indicating a cause or just showing the result of the paper stopping , as the page in the outer left path of the duplex unit was sitting on the associated sensor flag . Tested that sensor with the SP mode for that , seemed fine . Pulled the cover on the duplex unit rear side , test ran the 2 motors , on/off fine . Saw a 1-way bearing on 1 of the gears near the motors , worked it a bit , seemed to catch consistently . I don't see this unit much , have the service manuals for the machine and the duplex unit . Any ideas on what may need to be done or if there are any tech bulletins relating to this problem ? Thanks in advance , Ark .

[jimmcgee]

Hi,

The APPD1_S in the Jam Report is the actual jam. The report does not log the other pages in the train. APPD1_S indicates that the lead edge has been detected but the trail edge hasn't. The one way clutch may be slipping. Try a bit of WD40 in the clutch, if this improve the operation then it's probably the clutch or the shaft, it may be worn after 1M+ copies.

[kirkeb]

I would try replacing the delivery turnover unit first. That is usually the culprit. Check the "fingers" on the reverse gate on the left door unit to make sure none are broken although if they are it usually jams every time. Also if you have an FN6 finisher on the machine, the solenoid on that operates the gate on the paper entrance end could be misfiring once in awhile. The shaft of the gate could be broken or the frame of the finisher could be broken as well. I did have one occasion where due to the number of page passing through the finisher, actual grooves had been cut into the guides and the paper was catching on them.

[moose55]

I would try replacing the delivery turnover unit first. That is usually the culprit. Check the "fingers" on the reverse gate on the left door unit to make sure none are broken although if they are it usually jams every time. Also if you have an FN6 finisher on the machine, the solenoid on that operates the gate on the paper entrance end could be misfiring once in awhile. The shaft of the gate could be broken or the frame of the finisher could be broken as well. I did have one occasion where due to the number of page passing through the finisher, actual grooves had been cut into the guides and the paper was catching on them.

I second the motion on replacing the turn over unit. These should be replaced about every 300K or so.