It's a Seagate. You're saying it doesn't click? If it spins up, clicks and spins down, then most probably heads are gone.
The pads on the PCB look like normal corrosion to me, you can use soft pencil eraser to clean them and see if it makes any difference. However,if it clicks, I strongly suggest against powering it up again.
If it doesn't click then it could be a lot of things and a terminal output is needed to determine the problem.
I suggest you contact Jon at
http://www.datasaversllc.com for more.
Good luck!