Hey everyone, I picked up a Sony WM-EX562 last month. It looked great cosmetically, but I noticed it was making a clicking sound during playback. After cracking it open, I found the center gear was cracked—pretty common issue, as I found out after digging through the forums here. Big thanks to Valentin for his detailed post on this—super helpful! I ended up ordering a replacement center gear from eBay, and the gear swap itself went smoothly. However, after reassembling the unit, I ran into a new issue: playback is way too fast, and adjusting the speed control potentiometer has zero effect. I’ve double-checked all the motor connections, and made sure all the switches are properly engaged, but no luck so far. Did I damage anything while disassembly/reassembly, or while soldering the motor pins? Any help would be really helpful.
It's certain something had been damaged or not installed correctly when removing/re-installing the PCB. I think there was another member having a similar problem on a SONY WM-EX, so would recommend searching for that thread using Google (renders better results than forum's own search). Would look at small SMD resistors and capacitors, since these are the easiest to rip off the board.
@Valentin checked the pcb for any obvious damage or missing smd components. Cant find any. Could I have damaged the motor pins itself if I heated it too much? I checked the fwd/rev switch for continuity and its fine. Mechanism engages correctly into all modes, so no issues there.
Oops, I've figured out the mistake I've made. I think I accidentally glued the clutch assembly together while installing the new gear. I used watery super glue, and it must have seeped into the clutch—now there's no slip between the small bottom gear and the ring gear. So the take-up reel is pulling the tape directly through the capstan and pinch roller, which explains the overspeed issue. Now I need to figure out a way to loosen or dissolve the glue without damaging any of the surrounding plastic. If anyone has suggestions on how to safely reverse this kind of glue mess, I’m all ears.
As a suggestion for others reading the thread, the magnetic part of the clutch should be removed when glueing the new gear. This way even if the glue sips out, it's easy to clean after. For this particular situation, I would try to soak the assembly in IPA and force the 2 gears to rotate hoping the magnetic part won't break.
I'll try soaking it in IPA. Also reading online, POM is not affected by acetone, but there might be other plastics in the assembly that might dissolve.
