Riso GR3770 Print Problem

[axlefreed]

Good Afternoon,

I have a GR3770 that is giving me a problem I have not encountered before. The unit prints between 8 and 12 times and then misfeeds, the misfeed has the image too low on the page, I reset and start again, get the 8-12 prints and it misfeeds again... I have tested the Paper detection sensor (Test Code 1) and it passes.

Any help with this issuse would be greatly appreciated!

thank you,

Paul.

[20gaugeO/U]

TM #6 is the paper In sensor. Remove feed tire assy and test with a strip of paper rapidly. If you can create a non acceptable beep sequence then the sensor is bad.

[Kopyrtek]

Check your feed tires and stripper pad for wear.Clean the tires with soap and water for better grip.If the pad has a cup feel to it, its time to change it.

[axlefreed]

Hi there,

OK, I set test mode 6 and the sensor is high (short beep) when paper in and low (long beep) when out, I take that to mean that the sensor is functioning. This issue started last week, I've had the unit about one year and have not experienced any problems to this point. I've checked the stripper pad, cleaned it and pressure roller, again, feeds 8-12 sheets then misfeeds... can a weak scraper spring cause this? also, I can spin the feed tires backward with a little pressure, should I be able to do that?

Your help is appreciated, our Riso tech had a major motorcycle accident and there is no one in the area for service, thus, I have be promoted!

again, thanks,

Paul.

[20gaugeO/U]

Does it jam on all 5 speeds and with different sizes of paper? When it jams how is the reg on the page?

Don't worry about the scraper spring but there might be a double feed detection switch in there that is causing your problem. When you remove the 4 screws for the sep assy is there a 2 pin connector you have to disconnect? If there is place tighten the screw all the way so that the actuator never comes close to the slide plate. Or clean and score the 2 springs on the long silver guide roller that are in the 2nd paper feed area. Have to remove the entire roller to do this. Or the stage cover or drum handle detect switches are arcing and causing false jams.

Congrats on the promotion!

[joelsa12]

with the image too low on the paper it makes me believe that the paper is not getting under drum on time. did you check the feed tires? watch them while the machine is running. when it jams see if one of them does not turn. on the hubs of these wheels there one way bearings if you will. i have seen them get dirty or fail and cause the problem that you are speaking of.