Testing Starter

How long is "cranking awhile?" I'd suspect a bad cable or bad cable connections.

The problem with a bad starter of course is that it will "amplify" other marginal stuff. If the battery is a little old, or a little on the light side, or if the cable clamps are marginal, or a little on the light gauge side, then a heavy starter draw will cause things like hot cables.

But the OTHER possibility is that the cable itself is the whole problem!!!

You have a multimeter? clip one lead to the starter stud, and stab the other end directly into the top of the battery post. Crank the engine (jumper the starter relay.) If you have a volt reading of more than about .3V (three tenths of one volt) either the battery clamp needs cleaned, the cable is bad, or both.