[dpom75]

So my wife bought this sweet looking and mostly functioning Beocord 4500 cassette deck for my birthday. Luckily it also came with a nonworking Adcom 535ii amp that was much easier to repair.

So I bought the Service Manual and disassembled to troubleshoot why the deck won’t play or fast forward/rewind for more than 3 seconds, and eats tapes if left on play too long.

using the service manual I learned there are tons of special tools for head alignment and calibration, level, and bias. The only two settings I can adjust are torque and tape sensor. Since unit is already apart I easily adjusted the tape sensor which was grossly out of spec.

so my problem appears to be with the idler mechanism. The spur gear appears to be 0.5 mm away from the idler gear (no rubber it’s gears on this model). I will attach some photos from different angles. Just looking for ideas, parts aren’t available and part units are $150 and up on the bay so this one may be headed there soon.

I have looked really closely and I don’t see any damaged gear cogs, it is just a gap that doesn’t appear adjustable except for maybe the motor torque value is all I can figure. Adjusting that is easy enough although I don’t have the special tool I can just start turning the pot in both directions to see if it brings the idler closer to the spur gear.

thoughts? Wanted to reach out before I reassemble.

[Yvo Wiskerke]

Did you ever fix this? I have a Beocord 3500 that’s playing, but not rewinding or forwarding. Seems to be a similar problem. Mine is a type1 deck with only one belt. I am suspecting the belt as well, since it’s a bit loose.

I’ve checked voltages, manually checked the solenoids, signals for forward and rewind. It all seems to work from an electronic perspective.

When I put a tape in it, it won’t even forward or rewind, but when I hold the cassette detection switch it does for two to three seconds. That’s when the tape detection sensor kicks in and stops and switches off the whole machine.

Thoughts anyone?

[Author]

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