Is it Legal to Republish Maunals?

I work for a very small online company that sells used machinery (relatively inexpensive general laboratory equipment). I would like to know if it is legal for us to scan manuals for these items and publish them on our website. We are based in NY.

A link to a credible answer would be greatly appreciated.

If the maker of the equipment has a website offering their manual for download, you can publish a link to their site without problems. Otherwise, you should not re-publish copyrighted material without the written permission of the owner of the manual.