Try Disksalv, sounds like your harddisk needs error correction and re-validation. Disksalv can do both provided the partition size is less than 2Gb and the drive is less than 4Gb and your using FFS, FFSIntl, or OFS.
You could make a bootable Workbench disk with Disksalv on it and run it from floppy. If you harddisk is using scsi.device, you should be able to access it using a standard workbench floppy, can be version 2.0 upwards to 3.1.
