The other idea is the root cause is not in the motor but in the clamping mechanism. Don't know how complicated it is but certainly something blocking it. Hope external thing ( piece of plastic, small part of cd disk, piece of dirt), If external a blowing or using vacuum cleaner would help. If internal failure ( gear wheels went out, or sometimes a spring which likes to jump out) try to find out what should happen when motor turns and what not allows to do that.

If you don't have any idea maybe it's possible to take out whole sledge and ask someone skilled in mechanics ( a watchmaker ?).

I never dealt with clamper, maybe someone on this forum did.

If you rotate the big gearwheel at the bottom, then you can check whether the mechanism works.

If the set goes into standby, then it could be that the clampermotor draws to much current.

The clampermotor is controlled and fed by the motorcontrolboard next to the powersupplyboard.

The smaller board in the sledge functions only as passthrough.

Don't want to bother you again. But please imagine that someone sent to you a complete sledge in a good condition. So you will have to take out the existing sledge to be replaced by new one. If so, you could do it now in order to examine it and at least be sure that the problem is in that sledge an not outside ( e.g. in motor control board or clamping "jaws")

hi

I know how hard it can be when you do not have more ideas in stock ot halp.
Try to unplug the clamper motor and place a small bulb instead.
If it lights up then you know that the clamper motor is in a malfunction.
If it does not light up, it will be a fault in the connection or on the motor PCB .
At least I think so.

Hi Beobuddy.

It sounds like you know this machine well. How would one check motor control? I have a Mk II with a slightly different problem. The clamper does close (eventually) and will play a CD but it will not change position manually or automatically.

TIA. :)

Does the sledge releases the cd, when you choose another cd?

When it releases the cd's try to change the position of the sledge by opeming the glasdoor first. That way the sledge should move slower.

When you release the sledge by turning the big gearwheel at the bottom, set the sledge at the sledge at the 6th positiion. Then turn on the power and look if the sledge moves slowly to the first positiion. (that's part of the startuproutine).

The motor inside the sledge which clamps and releases the cd/sledge, often fails. This complete mechanism become dirty with dried out grease which causes the motor to fail.

Hey Beobuddy

Hi Mike,

I've actually registered an account to help your case (hello to all the forum members!)

I had a similar case with one of my BS9000 - the magnet in the clamper (part 9119 in the repair manual for MKIII) was stuck together with the turntable. You are absolutely correct that there is no electromagnetic release, it's only about how high the clamper is over the turntable. The turntable is being moved up and down by the rocker arm (part 9134 in a repair manual), which as I understand you have bent a bit so it operates better. Have you entered test mode and tried no 71 after assembling everything back? Is it still not opening?

If not, then my bet is that your clamper is simply tilted towards the sledge and so the magnet is close enough to catch the turntable. The clamper (part 9116) has two adjustment screws hidden under the top plate (part 9114). Just remove the glass door, then the round cover (part 9113) and after opening the top plate you have two small hex key bolts that you can loosen to lift the clamper. Does it detach now? Can you run the full test mode 71?

If that's still not enough, then have a look on how is the clamper attached to the sledge. There are just two metal plates (parts 9115) screwed into the clamper and holding it in place. If you remove them, you can actually see that there is a pivot point next to each of them - all these metal plates are doing is to fix the clamper between the adjustment screws mentioned in the previous point and the pivot points. It is possible that the pivots are a bit worn, so you can potentially screw the plates tighter, bent them slightly or lift the pivot points by adding a small plastic washer or something similar.

Here a side note - the whole sledge, as the rest of the BS9000, is a wonderful mix of metal and plastic parts moving against each other. I very much doubt that the metal parts are really bending under this minor stress of the usage, but I can fully understand that the plastic pieces are wearing out from the friction. This gives an impression that the metal parts are bent, but in reality it's the plastic pieces that are responsible for catching some slack.

After trying these steps, please run the test modes, first no 27 to erase the saved errors, then 71 to see if the mechanism is working fine.

For me it was like a millionth problem I had with that BS9000 and it took me a while to sort everything out, but now works like a charm. And beautiful it is.