Hello,
I just finished repairing the LU-202 that came with our machine. It was broken when we got it, and I thought by sharing my experience repairing it hopefully you can avoid the mistakes I did while trying to get everything working.
First of all, I am not a technician, I just maintain my machines following the manual and by sometimes consulting the experts on this forum. With that out of the way:
When I first opened the unit up, it looked like a bomb had gone off; All of the wires were unusable in some way; some had broken while others had their plastic lining roughened up or peeled off. While most of the pulleys and structural elements of the lift plate were bent or otherwise deformed. I have no idea what the previous owners did to the unit, but it looked like the KM tech maintaining the machine had bend some things back into place (evident by the grip marks made by a pair of pliers) but obviously that didn't hold.
As it turned out, you can't bend them back into place. Almost all the parts in this unit are made from some soft aluminum alloy. I replaced all of the bent pulley shafts, but didn't replace the front bar on the lift plate that the two front pulleys attach onto. This was a mistake, as it easily bent back into its original deformed shape, after me making a mistake while putting the lift wires in their correct positions.
Honestly, if a unit with a problem like mine comes your way, replace everything that has been damaged or deformed in any way. It is not worth the risk. The whole lift mechanism is flimsy and very difficult to repair. It took me 2-3 hours on the 2nd try to disassemble and reassemble everything. I don't know why KM went with this design instead of using something more solid like e.g. leadscrews with a timing belt.
I had a hard time understanding the manual on this one, so here is a quick summary of what you need to do. This is not meant to substitute the instructions provided by the manual, it's just to (hopefully) make your life a bit easier understanding it.
• Start by doing one side first, it can be either the drive or the operator side. Install the lift wires from the one sitting most inner to the axle to the one sitting most outer to the axle. On the final one, do not try to pass the wire from all its pulleys and then trying to attach the spring to the body of the unit. Instead, leave the wire off the 2nd to last pulley, install the spring, and then attach the wire to that pulley.
• Repeat roughly the same procedure for the other side.
• Test if everything works! It is very easy to get something wrong, trust me! Using something like a small Allen wrench, rotate the drive shaft, while having another person on the other side tell you if everything works as it should. Be very careful. If one of the tension springs start to deform (it shouldn't), stop immediately and check, most likely you have wound a wire the wrong way. Lift the plate fully up and fully down a couple of times to make sure it works reliably.
• Re install the gear box bearing in mind that you have to align the big central black gear with the positioning sensors before putting on the last gear.
Finally, using a spirit level, push the feed mechanism down and jig the door so the lift plate lifts to the upmost position and perform the paper lift horizontal adjustment so the unit feeds paper reliably. Mine worked reliably after performing this adjustment.
I am also attaching pictures of the unit with the wires in their correct positions, since the pictures found on the manual weren't very helpful for me. Hopefully you find this useful.
IMG_20210224_104740-min.jpgIMG_20210224_104751-min.jpgIMG_20210224_104757 - Copy-min.jpgIMG_20210224_104803 - Copy-min.jpgIMG_20210224_132002-min.jpg
Regards,
Orestes.
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