Checking the jumper pins on the drive I found that one was bent and possibly touching another.
Booted with CD1 and tried to reinstall lilo. First time it did not work, but inexplicably it did work the second time! Hurrah.
The Acronis Migrate easy is a nice ultiliy, even if it must be paid for. It is made by Acronis who describes themselves as "partners" in the ASP Linux project.