Aiwa HS-PX347: opening the case and replacing the belt

Hello,
I recently got a HS-PX347 from aiwa. The belt probably needs to be replaced. The case has an opening behavior I never met on my two other Walkmans. It looks simple at first sight with only 5 screws to remove. I can raise the case from the battery trap side as you can see on this picture

But as you can see, the battery door which is fixed to the internal body prevents me to raise the case completely. I tried to remove the plastic part of the battery door with no success. Maybe it is not intended to be removed or I didn't do it the right way. Note that unlike the px377 I opened recently, there is no screw inside the cassette compartment.
Any idea will be helpful. Thanks.

Here are some photos of every side of the device:

 

The battery door needs to come out for sure on all models with this design. But I suspect it's just the plastic part of it that needs to come out, without the metal insert.

I attached a picture of a Panasonic RQ-S25 that has a very similar battery cover . In this case, there is a catch that keeps the metal part from coming out of the plastic part. When the catch is released, the plastic part slides outwards. I believe the AIWA is very similar in this regard.

 

Yes, the metal insert of the battery door is fixed to the internal body and must remain in place. The plastic part is the piece which has to be removed to allow the full case opening. I didn't figure out how to do this until now and I din't want to force and break something. Thank you for the picture, I'll check on the PX347 in the evening. As I remember, it is very similar to this RQ-S25.

 

To remove the plastic part on the battery door, you must gently lever on the metal tab as shown on the picture while sliding the plastic piece to the left.
Then the case opens flawlessly.

 

Next step: the belt is not directly accessible, so the electronic card must be removed first.
There are 5 screws. 3 of them are accessible through a hole in the card.

And now the tricky part: as you can see, there is a tablecloth (red arrow at the bottom of the picture). So I assume the card must be removed starting from the top (battery side).
But as you can see on the view below, this part of the card is attached to the body.

I'm not sure about the next step to detach the card from the body on this side. Do I have to unsolder something (I don't think so, it must be easier) ? Or Is there a way to detach the whole black plastic clip (see red rectangle on the picture above) ?

 

I think the holes marked in red have nothing to do with the PCB mounting, they're probably just plastic mounting points.

The only screw that I can see that obviously secures the PCB is the one marked orange (it is possible that this is the only one, but look unerneath that copper shield as well).
It also looks like the motor (4 pins marked orange) needs to be desoldered (typical in this type of walkman with 3 phase brushless motor).
However pay attention not to apply too much heat, as usually these motors have the coils printed on a flex PCB which can melt from high temperature.
The switch depicted in the last picture (a cassette in and TYPE I/TYPE II detector) may or may not need to be desoldered. I would try do lift the PCB without desoldering it and see what happens.
The head flex cable (marked with an arrow) can probably remain in place, as the board will tilt to that side once everyting else is removed.

 

I actually missed the grey screw you pointed me in orange. Thank you. But the others (black screws) also have to be removed.
For example, on this picture you can see that the screw pointed by the red arrow holds the jack port.

There is no screw behind the copper shield.

Now the (very) tricky part again. This picture may help you confirm if the motor must to be desoldered. Note: the screw below the white plastic piece is for the cassette door opening mechanism.

The PCB is very thin and fragile especially at the switch (cassette in + type I/type II) location. I tried to (gently) lift the PCB there with no success. Maybe this picture will give more information about the way the PCB is attached to the body.


This is the most difficult device to disassemble that I have encountered so far.

 

Informative pictures, it is now clear that the other black ones need to be removed as well (in the first pictures it wasn't very clear these were actually screws or just plastic locating pins).

In units with similar design that I have opened before (mostly SONY and Panasonic), the motor had to be desoldered. You can try to gently lift the PCB and see if it moves at all, but I can't see how the PCB would come out without doing that.

The TYPE I/TYPE II swtich needs to be desoldered, it's more obvious from this angle: it's recessed in the inside of the mechanism frame, so it can't slide upwards. However, as with the motor, be careful as these switches can melt relatively easy from high temperature.

Something else to look on this type of design is a solenoid: if it has one, that needs to be desoldered as well. Now that I look carefully at the PCB it's likely to be the one marked blue.



In regard to desoldering, I recommend using a good quality solder wick. Something similar to this one: https://www.tme.eu/fr/en/details/hq-wick-s3/desoldering-wicks/chemtronics/
First apply some fresh leaded solder and then use the solder wick to desolder the switch, motor and solenoid.

 

Well, well, well. I'll plan this for later, when I'll feel more confident and with better quality solder wick.
Thank you for your help so far.