Mechanic's stethoscope.
https://diqn32j8nouaz.cloudfront.net...e_fullsize.jpg
Previously:
https://www.homemadetools.net/forum/...614#post132677
Printable View
Mechanic's stethoscope.
https://diqn32j8nouaz.cloudfront.net...e_fullsize.jpg
Previously:
https://www.homemadetools.net/forum/...614#post132677
Nothing like the sensation of using one of those to diagnose a weird engine noise and then accidentally bumping a rotating pulley.
I bought one years ago. Works good. Put it against an alternator and you can hear it cogging magnetically as it rotates past each phase.