IBM 4869 5.25" floppy drive

Hi, The other week I bought an IBM 4869 5.25" floppy drive. This is an external unit that hooks up to a PC via a 37-way D connector. The case is massive, for a simple floppy drive. Anyway, I can't get it to work properly. It is probably a 360K drive mechanism, and my PC (Philips 386SX AT clone) boots normally with this type of drive set in the backup RAM. I can format disks and use DIR, but reading or writing any files always gives an Abort/Retry/Cancel error. Unsurprisingly, cleaning the heads made no difference. Actually, to elaborate on this copying a load of files to a newly- formatted disk gives an error after copying (say) the first two files. Does this drive have some non-standard pinout, different from the 37-way D 5.25" port on the back of the PC, or maybe only work with IBM PS/2 machines? If it is just faulty, what might the problem be? The cable is unlikely I think, as is the power supply. The casing has a couple of tamperproof Torx screws. I'd like to know what size they are so that I can buy a suitable screwdriver bit. Finally, on another subject, if anyone has an old PC with at least three ISA slots (386SX would be fine) I could give it a good home. -- Mark