RISO GR3750 Paper Jam Check Paper Feed Area Error

[Iowatech]

Re: RISO GR3750 Paper Jam Check Paper Feed Area Error

An update to the suction belt tensioner on the GR3750. Here is a video of the failure (it slips around 30 seconds then completely towards the end) :

I cannot visibly see what is causing the tensioner to slip when I look at the clutch assembly through the bottom, back left side behind the PCB. The slip is gradual as you can see from the video so it seems like some force is pulling it off the tensioner shaft.

In terms of looking at the suction clutch assembly, what would I be looking for? Something loose or off kilter. You can also see from the video that there is a center screw hole in the tensioner plate that is empty. When I got the machine the plate was attached with the top screw and a center screw. I moved the center one down to the lower part of the plate. Tried both configurations and still the belt slips.

Thanks in advance for the help!

The tensioner pulley needs to be replaced.
The bushing is pressed into the pulley when new, and the fit of the bushing in the pulley has failed on your machine. That's why the pulley moves outward as the belt slips off.

[filmplane]

Re: RISO GR3750 Paper Jam Check Paper Feed Area Error

The tensioner pulley needs to be replaced.
The bushing is pressed into the pulley when new, and the fit of the bushing in the pulley has failed on your machine. That's why the pulley moves outward as the belt slips off.

Ok good to know. I can find that pulley replacement part and hopefully this will solve the paper jamming issues once and for all. Looks like the replacement will require the removal of the collar in front of the shaft there? I wonder if I should just replace the pulley or the entire tension pulley bracket?

Thanks again!

[Iowatech]

Re: RISO GR3750 Paper Jam Check Paper Feed Area Error

It would be easier to replace the entire bracket with the pulley. Especially if you haven't ever removed the type of clip that holds the pulley on the shaft on the bracket. Just put the screws back the way you found them when you first looked at the tensioner bracket. Unless there is something else that is terribly wrong, the standard belt tension should be adequate.

[filmplane]

Re: RISO GR3750 Paper Jam Check Paper Feed Area Error

It would be easier to replace the entire bracket with the pulley. Especially if you haven't ever removed the type of clip that holds the pulley on the shaft on the bracket. Just put the screws back the way you found them when you first looked at the tensioner bracket. Unless there is something else that is terribly wrong, the standard belt tension should be adequate.

Ok, will do. Hopefully I can remember the general position of where it was originally. I will try to post an update when the parts arrive. I found that Google verification has a good inventory of Riso parts and will order from there. Thanks for the help!

[Iowatech]

Re: RISO GR3750 Paper Jam Check Paper Feed Area Error

Ok, will do. Hopefully I can remember the general position of where it was originally. I will try to post an update when the parts arrive. I found that Google verification has a good inventory of Riso parts and will order from there. Thanks for the help!

Don't use the adjuster slot on the bracket, just use the hole above the slot for the non-pivot screw.

[filmplane]

Re: RISO GR3750 Paper Jam Check Paper Feed Area Error

Don't use the adjuster slot on the bracket, just use the hole above the slot for the non-pivot screw.

Ok great, thank you for clarifying which slot I should use for placement. Also, you mentioned the clip of the pulley being hard to work with. Can you describe the correct method of removing that type of clip? I have to replace the plastic hook mechanism (part no 017-11808-007) that is attached to the paper feed pressure adjustment lever and it has one of those clips.

hook.jpg

I used a needle nose to slip it off but it bent it a little. Any tips would be greatly appreciated. Thanks!

[Iowatech]

Re: RISO GR3750 Paper Jam Check Paper Feed Area Error

Ok great, thank you for clarifying which slot I should use for placement. Also, you mentioned the clip of the pulley being hard to work with. Can you describe the correct method of removing that type of clip? I have to replace the plastic hook mechanism (part no 017-11808-007) that is attached to the paper feed pressure adjustment lever and it has one of those clips.

[ATTACH=CONFIG]27278[/ATTACH]

I used a needle nose to slip it off but it bent it a little. Any tips would be greatly appreciated. Thanks!

I usually use a jeweler's screwdriver to pry the clip off.
You might not have to do anything to the bent clip, just put it back on the shaft and then try moving it around with your fingers. If the clip moves around too much take it back off and squeeze it gently with some pliers, otherwise the clip will be OK.

[filmplane]

Re: RISO GR3750 Paper Jam Check Paper Feed Area Error

I usually use a jeweler's screwdriver to pry the clip off.
You might not have to do anything to the bent clip, just put it back on the shaft and then try moving it around with your fingers. If the clip moves around too much take it back off and squeeze it gently with some pliers, otherwise the clip will be OK.

Ok great - thanks again for the help!

[LA TECH]

Re: RISO GR3750 Paper Jam Check Paper Feed Area Error

Your Riso is out of adjustment, it needs the three critical timing point to be adjusted, otherwise no matter what you do adjusting it it will give you problems, the GR service manual tell you how to do this is simple if you know what you are doing, loose the main drive and lock the main drive gear and the other points also check the air pump to see if the "O" ring is not worn out it will cause jamming problems too, if you are not familiar with it call a Riso rep. So they can do all the adjustment hopefully he want to work on it because all the Riso tech wants to work on the new Riso series

[filmplane]

Re: RISO GR3750 Paper Jam Check Paper Feed Area Error

Your Riso is out of adjustment, it needs the three critical timing point to be adjusted, otherwise no matter what you do adjusting it it will give you problems, the GR service manual tell you how to do this is simple if you know what you are doing, loose the main drive and lock the main drive gear and the other points also check the air pump to see if the "O" ring is not worn out it will cause jamming problems too, if you are not familiar with it call a Riso rep. So they can do all the adjustment hopefully he want to work on it because all the Riso tech wants to work on the new Riso series

LA TECH, thanks for the reply and advice. I think I now have the timing in order but have to wait on the tensioner pulley part to see if all is well. I will definitely check the air pump and see if the O ring is ok. My local Riso rep is an hour away and charges $125 an hour including travel. Hopefully I won't have to call just yet...

[filmplane]

Re: RISO GR3750 Paper Jam Check Paper Feed Area Error

Iowa Tech and LA Tech - just a quick update to this thread - the GR3750 is ONLINE! I finally tracked down a new tensioner pulley and bracket. On the failing one, the bushing for the pulley was over worn causing it to slip. The 'new' one I ordered seems to be holding for now. For extra measure, I took the worn one to a machine shop and they fixed that one as well so I have a back up. Thanks again for all the help!!!