Riso GR 3750 Error msg ''Install Ink cartridge"

[DAG COPIERS & COMPUTERS]

Dear Riso gurus, I have this problem with the above machine which was not inking at all, it could display some message like 'replace ink cartridge', we had the ink pump replaced and we tested the drum on a model gr3710 , it worked well; at least we made some 300 copies. We then had the drum unit properly packed and sent back to the customer, some 450miles away. Now the customer says that immediately he inserted it in the machine, a gr3750, it displays 'install ink cartridge'. I am confused, could someone please advice me on how to go about this problem? Thanks in advance.

[Iowatech]

I'm not sure if the GR3710 is a good test bed for a GR3750 drum. I could be wrong, though. That being said:
First thing I'd have that place do is the working memory reset (hold down the Reset key while turning the machine on, and keep holding the key down until the sounds of the machine initializing get quieter). While that is somewhat unlikely to help, it still could, and it is really easy to do, too.
Then I'd check the ink board, the one that has the press switches that detect the tab on the ink bottles.
The connector from the drum to the GR3750 might be causing the problem. Might be a blown fuse on the power supply board as well, not sure which one but that is easy enough to check with a meter. Hope the main board hasn't gone bad, that would be the end of that GR3750.
Well, hope that helps.

[DAG COPIERS & COMPUTERS]

Thanks Iowatech for you advise. I'm sorry for having taken long to reply, but ultimately I got solutions to this particular problem, and had machine fixed. First I removed the 'ink bottle guide' from the squeegee unit in order to access the 'ink bottle detect switch', there's a row of three micro switches, and I did Ohmmeter check on each to ensure that they were all working. I realized then that my ink bottle was not pressing the ink bottle switch properly and that's why it was indicating 'install ink cartridge'; by pushing the ink bottle firmly inside and slightly twisting it to the left, the switch could properly make contact and the above message disappears and the machine works.

The second problem of not inking at all had to do with some poor contact of connectors on the drum PCB; I removed the board, applied a bit of WD 40 on a rug and used it to clean the board, after putting it back, it started inking normally! It is now two weeks since and the machine is still working very well. This has been my experience. I hope it can be of help to others who might find themselves in similar situation.
Thank you.

[Iowatech]

I realized then that my ink bottle was not pressing the ink bottle switch properly and that's why it was indicating 'install ink cartridge'; by pushing the ink bottle firmly inside and slightly twisting it to the left, the switch could properly make contact and the above message disappears and the machine works.

Depending on the age of that ink bottle, you might want to keep an eye on that machine. Riso ink bottles tend to expand in diameter as they age, or at least I've seen that on GR machines. If the bottle expands too far, it will take a lot of work to get it out of the drum. And the first time I had to deal with that problem, it caused a really big mess.

[DAG COPIERS & COMPUTERS]

Depending on the age of that ink bottle, you might want to keep an eye on that machine. Riso ink bottles tend to expand in diameter as they age, or at least I've seen that on GR machines. If the bottle expands too far, it will take a lot of work to get it out of the drum. And the first time I had to deal with that problem, it caused a really big mess.

Point taken, I totally agree with you.