Hi, I have a Sony Walkman WM-F501 model that I've had for a while. Recently a problem developed that I could not get any playback on the FWD side, the tape would just stop spinning and the auto reverse would kick in, or they would only spin momentarily before stopping, and then the player would automatically set it to stop. Playing it back on the REV side does work but there's an audible clicking noise along with the motor sound and the audio sounds wonky as if the motor is struggling to play it at full speed. Do note the fast forward and rewind functions with a cassette inserted on both forward and reverse sides. Any help knowing with the issue is appreciated.
Your problem is a cracked takeup reel ring gear, common problem on many series using this type of table reel design: WM-10/20/30, WM-100/200/500 series. Solution is to repair this ring gear using epoxy. You remove the table reel, clean the crack area with IPA, add the epoxy and let it harden to the point where it's still soft enough to mold the teeth into it, but hard enough that the epoxy is not sticky anymore. Then put the reel back and mold the new teeth by rotating the reel so the ring gear makes contact with driving gear. See picture attached.
Thank you for the advice. I'll have a look at it in the afternoon but accessing it is just by taking that plate to the right of the big reel off if Im not missing anything. Mechanism looks nearly identical to on my device.
Yes, on WM-100/200/500 series table reel is very easy to remove: just open the door and remove the split washer holding it while keeping the reel pressed with your finger (it's under tension as there's a spring underneath). On WM10/20/30 it's way more complicated requiring disassembly of the entire mechanism. But fortunately you're not in this situation.
It is your WM-504, it's the only good picture I have with the repair of this gear. Repairs done on WM-10/20/30 units are not as visible as the teeth are recessed inside the chassis.
