FS3040 Paper Meandering

**OperatorError** · 09-19-2018

My machine will run single sided all day long. Running duplex the paper drifts to the left and eventually runs out of the paper path and crashes.

I included a picture of the rear of the machine with the fuser removed. The paper is in the duplex tray, you can see the left side of the paper is against the edge with no room for error, the right side however looks fine. Also is a picture of the jam under the drum when the paper is so far it crashes.

Customer does not run labels, no scraps of paper found, no springs or idle rollers out of place. No issues under the dev unit. Machine only has 36k, fuser is newer.

Jam is code is usually 70 but the the drift is the problem.

Anyone seen this before? Or I am in for a huge disassemble.

Thanks in advance.

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Gary E · 09-19-2018

Replace the paper tray.

**OperatorError** · 09-19-2018

Thanks...What is the reason? I know the contour of the cassette secures the duplex tray in place and appeared to be doing just that when i looked in thru the back of the machine.

**Scott** · 09-20-2018

Don't think its paper drawer, once it's out of the drawer it doesn't go back and it doesn't do it on single sided. The problem is somewhere in duplex unit. Try different drawers and see if it quits and manual BP

**tmaged** · 09-21-2018

It's a known issue. Pull the center gear out of the cassette & move the left guide in one tooth & reassemble. Guaranteed to fix it.

**OperatorError** · 09-21-2018

Sounds promising, thanks. I wish the first guy would've gave a pinch of reasoning behind his (correct) solution. I am going back tomorrow and hope for the best. By the way, how is this a known issue? Just word of mouth or a bulletin? I didn't see anything in my searches.

Thanks again.

**mita** · 09-21-2018

I have also seen the mylar shim where the fuser mounting screws are can cause skew. There usually is a shim on one side, swapping the shim to the other side resolved the issue.(Front to rear)

**OperatorError** · 10-01-2018

It was not the cassette...or the duplex unit...or the exit unit.

After tear down I found these large vertical feed rollers behind the bypass tray. As you can see the one on the left is not centered on the hub. The right was biased to the left as well but harder to see in the picture.

Single sided worked but going past this roller twice was enough to cause those intermittent jams.

Hope this helps someone in the future.

**blackcat4866** · 10-01-2018

Good to know! Is the photo after the re-aligning? I can't really see the rubber riding off the side of the pulley, but I can imagine what you're talking about.

Thanks for posting back. =^..^=

**OperatorError** · 10-02-2018

Not so much riding OFF the pulley, just cattywumpas towards the left. Here it is with a computer generated line, you can see the gap towards the bottom where the hub rail is.