USB Hard Drive Repeatingly Mounting/Ejecting

I’m running OSMC on a Raspberry Pi 3+ and I’m having an issue mounting a couple of external USB hard drives.

Both are 2.5" HDs, one 250GB and the other is 1TB, whose SATA bridge card went bad. I took them out of their cases, removed the SATA bridge card and got a USB/SATA cable to use with those drives. The cable HD combination works on my iMac and Linux laptop just fine. When I plug them into the RPi running OSMC they mount for a moment then eject, mount again eject, mount again eject…and this keep repeating with the drives making a clicking sound.

All the other external HD drives I have work. It’s just the two that I’m using the USB/SATA cable with that are having this problem.

Any idea what the issue may be?

Thanks.

If they are not self-powered or you are not using a powered hub, it’s probably that the Pi isn’t able to supply enough power to the drives, so they keep cycling.

This will almost certainly be power related. We recommend using a powered USB hub.

I’m not using a hub at all unless the RPi has one built into it. All the USB drives that plug directly into the RPi do work and pull the power from the USB ports on the RPi.
The only difference is the cable and I believe it’s pulling power form the USB also because it as a LED that light up.

You will need a powered hub then. The Pi will not be able to supply enough power for the drives.

This will work: 4 Port USB 3.0 Powered Hub - OSMC

I got a powered USB hub and that drive now works.
Thanks for the suggestions.