Why does tapping the starter motor with a heavy tool help when I can`t start my car sometimes?
This is called a “dead spot”….the electrical motor that makes up a starter is no different than any other electrical motor. There’s a shaft with large copper spools on it surrounded by magnets. The copper spools “chase” the energized magnets causing the motor to turn. A dead spot is usually on the magnetized portion of the motor….it’s charred most likely, it happens over time as little bits of debris, oil, etc get inside. When you tap it with a hammer you’re simply causing it to move slighltly, enough so that when you turn the key the “chasing” game can begin again. I’ve seen this problem for 20 years now, and have tapped more than a few starters myself. You’re not causing any harm by doing this but it’s a crap shoot…it may start with a hammer tap for another year or it may stop tomorrow. That “dead spot” is most likely getting bigger and a bit more scorched every time you start the car. It is possible for the starter to “catch” at just the right point and kick off a short in the
