Riso RP3100UI - Paper Feed Not Working

[unwork_inc]

Hello fellow users - I have a Riso RP3100UI which suddenly stopped feeding paper, the feed rollers are just not doing their job somehow

The machine gives no warnings or errors. Everything looks normal on the screen except that upon attempting to print, paper is not being fed. I can hear the drum spinning, getting ready to receive the paper, but after 5-6 turns the machine stops and gives me the standard G064 Paper Jam error, but the paper hasn't moved an inch. I'm attaching a video showing the behavior described here.

Here's a list of related tests I ran in Test Mode, along with their results:

400 - Paper Detect Sensor - YES (short beeps)
401 - Paper Size Sensor - YES (short beeps)
405 - Paper Feed Sensor - NO (long beeps)
457 - Auto Multi-Paper Feed Det. Adj. - NO: Error T98-422
656 - Paper Feed Test - NO: Error G064

It seems like the Paper Feed Sensor might be the culprit?
Please let me know if any of you can shed some light into this issue.

Kind regards
Mariano

[Iowatech]

If you haven't tried resetting the machine, you should try that first. The technique is the same for most every Riso including the RP line, and there are many posts about that here already.
Also, have the feed rollers ever been replaced on the machine? They're rated from the factory at 500,000 prints, although if you are running unusual paper they can wear out somewhat sooner.

[unwork_inc]

Thank you for sharing your insight

I did reset the machine by starting it up while pressing the Reset button –it was the very first thing I tried– but to no avail. The error persists.

Also, printer has less than 600.000 prints and feed rollers seem to be in good shape. The problem is that the rollers themselves aren't spinning at all.

[Iowatech]

The problem is that the rollers themselves aren't spinning at all.

I see. Well in that case you'll want to check the feed clutch, and possibly the paper tray height, too.
The clutch is in the back of the machine, attached to the driveshaft for the scraper roller. If you've never had the back off your machine, you'll want to be really careful back there as the frame is made out of stamped metal pieces and they have sharp edges. There's some pretty strong springs too. So be careful, or you will get hurt.
Look for a brownish color around the clutch, if you see any the clutch is worn out, and that is why the rollers aren't turning.
The paper tray height check and adjustment is on page 4-25 of your manual if you need it.
While you have the back off the machine, make sure the updated gears are on the machine as shown in the following:
gear update.pdf
Those drove the feed rollers.

[unwork_inc]

This is valuable insight, thank so you much for posting this.

I'm familiar with opening the back of the machine, I had to do that several times in order to remove a stuck drum and rotate the main gear.
Thanks again, I'll follow your suggestions this weekend when I have enough time then share the results here.

[unwork_inc]

Thank you iowatech's, your reply and insight helped me locate the problem. I'm sharing what I've done to fix it here, in case it helps someone else

- After removing the back cover, I've realized one of the screws was loose (circled red in photo below). This was causing the Sector Gear Assembly (triangular-shaped piece on photo) to jump out of position, preventing the Second Feed Section from doing its job.

2017-03-25 13.52.46 copy.jpg

Good luck