my old speedo/odometer combo broke (long story) so i bought another used one and put it in. It works ok, but the needle wavers up and down a bit. Great, speedo cable loose i assume. Just haven't had time to tighten it.

But also, now, after driving it, i found that it makes a rattling noise. From what i can tell, it is caused by (to be realll technical) the "part that spins" inside the "metal cap thingy" and the metal thing is lightly touching the "part that spins." and is causing the mettalic rattling noise. Anyone know if tightening the speedo cable should fix this?

Also, this being my first real car (i drove a tempo) i don't have a lot of experience fixing things. When i go to tighten the speedomter cable, how should i go about doing it?