This tutorial shows you how to replace the pinch roller on the SONY WM-D6C Professional walkman. It also applies on the older D6. The roller needs to be replaced if it shows cracks, indentation marks or glaze. Most older D6Cs and D6s will be in need of a new pinch roller. The first post includes the disassembly process, while the second shows the replacement of the pinch roller itself. The part can be found here: https://fixyouraudio.com/product/sony-wm-d6c-pinch-roller/
This part covers the replacement of the roller itself and part of the reassembly process. It doesn't show the full reassembly, as everything is just in reverse order of disassembly. Note it is important to clean the pinch roller after this service, because it's most likely contaminated with grease from your fingers and potentially oil from lubricating the shaft. It's also important to clean the roller regularly with a cotton swab immersed in IPA: as soon as the oxide marks become very visible (once every 10-20 cassettes played/recorded, depending on tape type and quality).
An excellent tutorial, however I would like to add one detail. When re-fitting the spring on the pinch roller bracket, check that it is in the correct position, otherwise the spring can rub on the pinch roller and even wear a groove into it.
Very good point, @Deb64 ! From the angle you took the picture it is very clear how the spring needs to routed.
