Riso GR3770 will not pull the paper through once it passes the initial feed assembly. The paper ''picks up'' just fine, but after the lead edge enters the machine, it kicks off impression and gives a ''paper jam'' error (sometimes in the paper feed area, sometimes under the drum). The first feed section is all new (tires and everything). What (and how) do I check on the second area?

7.2 Detecting Jams 7.2.1 Delay Jams 7.2.1.1 Delay Jam in Pickup Assembly 0010-4883 iR2016J / iR2016 / iR2020 / / iR2016i / iR2020i Delay Jam in Pickup Assembly The registration sensor cannot detect the leading edge of paper within the jam detection time interval after paper pickup started. T-7-2 7.2.1.2 Delay Jam in Delivery Assembly (Paper Leading Edge Jam at First Delivery Sensor/Wound Paper Jam at Fixing Assembly) 0011-0712 iR2016J / iR2016 / iR2020 / / iR2016i / iR2020i Paper Leading Edge Jam at First Delivery Sensor The first delivery sensor cannot detect presence of paper within the prescribed time after the registration clutch has been turned on. T-7-3 Wound Paper Jam at Fuser The first delivery sensor has detected absence of paper within the prescribed time after it detected presence of paper (within the prescribed time after the registration clutch had been turned on). T-7-4 7.2.2 Stationary Jams 7.2.2.1 Stationary Jam in Pickup Assembly 0010-4884 iR2016J / iR2016 / iR2020 / / iR2016i / iR2020i Stationary Jam in Pickup Assembly The registration sensor does not detect absence of paper within the prescribed time before the next leading edge of fed paper reaches the registration sensor. T-7-5 7.2.2.2 Stationary Jam in Delivery Assembly (Paper Trailing Edge Stationary Jam at First Delivery Sensor/Stationary Jam at First Delivery Sensor) 0011-0733 iR2016J / iR2016 / iR2020 / / iR2016i / iR2020i Paper Trailing Edge Stationary Jam at First Delivery Sensor The first delivery sensor cannot detect absence of paper within the prescribed time after the registration sensor has been turned off. T-7-6 Stationary Jam at First Delivery Sensor The first delivery sensor cannot detect absence of paper within the prescribed time after it has detected the leading edge of paper. T-7-7 7.2.3 Other Jams 7.2.3.1 Door Open Jam 0010-4886 iR2016J / iR2016 / iR2020 / / iR2016i / iR2020i Door Open Jam The door is opened when paper to be printed is in the paper feed path. 7.3 Cassette Pick-Up Unit 7.3.1 Overview 0010-4887 iR2016J / iR2016 / iR2020 / / iR2016i / iR2020i The paper picked up from the cassette is fed to the registration roller using the vertical path roller driven by the main motor (M204). The registration roller is not rotating when paper reaches there, so an arch is formed at the leading of the paper to prevent skewing. The DC controller PCB turns on the registration clutch (CL203) at the prescribed timing to transfer the main motor rotation to the registration roller, thus feeding the paper to the delivery tray through the transfer, sepa- Sensor/Solenoid Registration sensor (SR209) Pickup solenoid (SL202) Sensor/Registration clutch First delivery sensor (SR203) Registration clutch (CL203) Sensor/Registration clutch First delivery sensor (SR203) Registration clutch (CL203

If it is a spring cluths assembly simply remove it and clean the spring and the assembly with rubbing alcohol..then apply a drop of 3-1 oil on the spring and reassembly.......give that a try

refix your ink cartrdige also check there is not any paepr jam issue.
also some times printer neeed servicing creates this type of issue.

first try paper feed clutch.. make sure nothing is blocking paper path...

Try this, make a print from the by-pass tray, does it go OK or jam??
If it jams then there is a problem with the paper feed from the tray.
If it jams then
1-check the drum and see if there is an image on it( you can put a mark on the edge to see if it's rotating, thus eliminating the drum unit)
2-same for the reg roller
3-check for labels ar foreign objects

either the motor is not turning to lift it up or the gear is broken, do you hear the motor turning when the tray is pushed in? take the tray out and look in the back to see if there is anything blocking it also.

check and clean the pressure roller.see if that helps.

Riso's are famous for this, i will scrub the rubber timing roll with rubber rejuvenator and clean the steel roll with alcohol.

the riso paper feed clutches are weak compared to what they were in the GR series you may have to replace the clutch.

Sounds like you forgot to plug the High voltage transformer or a sensor back

Get a window cleaning product such as windowlene and a soft but LINT FREE cloth. Remove any paper from the feeder and turn off the machine

Look into to sheet feeder and identify any rubber areas. There should be a rubber pick up wheel and just beyond it a separator pad. There may also be a cork pad in the vicinity.

Use your cloth well dampened and clean all these item as best you can. You can rotate the wheels but ensure you go the correct direction and do not force anything that does not want to move. This will be chore as access is only easy for pixies. Once you have then cleaned and dried off, replace the paper and restore the power.

Try running a print job and see if it makes much difference. If it helps, then you will know that the pick up wheel and separator pad are worn out and could do with replacing.

The paper jam error is related to this issue as the printer is expecting the leading edge of the paper to pass its sensor and then 297mm later the trailing edge should pass the same point. If the machine feeds more than one sheet, the chances are that the paper length will be altered and the machine thinks a bit has been left behind.

Let me know how you get on