Put rebuilt Starter in car and it works, but whines.

[mrlynn]

Is it just a higher-pitch starter sound? Every time? That may be OK. But if you hear more of a brief screech, and only sometimes, then you may have a worn spot on the flywheel, so the starter gear is not engaging the teeth on the flywheel well. Unfortunately, replacing a flywheel is a major repair.

/Mr Lynn