HP Photosmart 7520, 7510, 7525, 7515 paper pickup gear Repair

ID: 124908

Description: It is a design flaw to connect a nylon gear on...

Steps:

1. Review this utube video You won't be doing all of that, but it's a good place to start.
2. Remove the ink cartridges, the duplexer/paper-jam-access-cover and the paper tray.
3. Remove lower side covers.
4. This is done by prying out the edge of of the cover that is next to the paper tray and pushing the edge out.
5. Once this face is out, push the cover back.

6. Remove 2x 15mm pop off right cover.
7. Split the part on the front and back, then the top. Pry up the top and tilt the top of the panel open, then pull the cover up and out.

8. Remove two 10mm screws.
9. Lift and pull out right cover
10. Note the left cover is plugged into the motherboard. Lift front, pull out.
11. lift off paper tray cover

12. Be gentle.
13. IMPORTANT, one has ZIF (zero-insertion -force) connector. Lift up the bar and then remove the cable. During reassembly, ensure the bar is up, insert the cable and push the bar down.
14. The cables go through ferrite collars. Leave the collars in place, but be sure to put the cables back through the collars during reassembly.
15. carefully move the cables to the back

16. Pop off two covers in the back.
17. Unsnap the hinges. This is tricky. Gently push the top assembly up. This will create a small gap between the hinge and the top. Slide a thin prying tool into the gap and pull gently down to release the hinge.
18. Once unsnapped, pull the top assembly away from the hinges. (You did carefully move the cables to the back before this step, right?)

19. Remove 6x 15mm screws
20. remove 3x 10mm screws, the third one is on the back.
21. disconnect the red/blue cable from the motherboard on the side and unhook from guides.
22. lift off top
23. Remove right side

24. Disconnect the front panel from the motherboard
25. Remove 2x 15mm screws.
26. Lift out front panel

27. Remove 4x 15mm screws
28. Remove 1x machine screw and disconnect remaining cables..
29. Disconnect linkage

30. A lot of tubing needs to stay connected. If it comes loose, it's really messy and hard to do.
31. Position the printer like the picture shows.
32. The second and third pictures show the location of the problem. I had tried the non-disassembly procedure, but it failed for me. You can see a glob of JB Weld.

33. OK, I got you here. I'm going to try to:
34. clean off all the JB Weld
35. Slide the gear over
36. put a couple of drops of Superglue on the splines, push the gear back over the splines and let cure while I eat a sandwich
37. Mix up some JB Weld and ensure that I get it 360 degrees and both sides. Wish me luck!

38. It's not much fun getting that printer engine back on. Put on you latex gloves.
39. Before you start, though, clean up those pinch wheels that grab the paper. alcohol, let dry, sandpaper them a little.
40. IMPORTANT: Get rotary-pulse encoder, the then clear plastic disk, needs to be clean and go into that "slot" (which is an opto-coupler, that counts the pulses.