TweetMarch 16, 2009
Our Tip of the Week concerns starter motors. Somewhere underneath your vehicle is a 12-volt starter motor similar to this one responsible for cranking that engine over. In most cases, it only takes a momentary crank for the engine to fire up. However, if you run into problems, like run out of fuel or have some tuning problem that requires an extended period of cranking, you've got to be aware that these things are not intended for continuous duty.
Ten to fifteen seconds of continuous cranking is the absolute maximum, followed by several minutes of cool-down time for the starter motor to cool down so you don't damage it. Now, if you run into problems and the car won't crank at all, it's an often-used trick by towtruck drivers or motor league personnel to get underneath the vehicle and hit the starter motor with a hammer while you're trying to start the vehicle. If the starter motor has worn brushes, this is a viable thing and will get it started. However, on modern cars with permanent magnet start motors, they're a little bit on the fragile side so you can't hit 'em too hard with a steel hammer.
Use a plastic hammer or a piece of wood and you only have to jar them slightly if the brushes are worn to get that last crank that'll get you going. It's a trick you can use but you've gotta go easy so you don't do damage.
That's your Tip of the Week.