Small Engines (Lawn Mowers, etc.): riding lawnmower, jumper wire, volt light


Question
I have an 11 year old Craftsman, 42" cut, 12.5 HP riding lawnmower.  I have had trouble starting it the last couple of times.  When I first try there is nothing.  I will try again and it will click.  I will try again and it will make a spinning noise.  I will try again and it will turn over slow and then start. Once it starts it seems to run fine. I was hoping you could tell me what might be wrong.  To have a service man come out and look at it is very expensive, and I have no means of taking it somewhere.

Thanks so much,

Lee

Answer
Hi Lee,

I suspect a weak battery but follow my No Crank proceedure below to check the other components.

I would check the starter first.  Jump the positive battery terminal to the starter and it should crank over. If so, skip to step 2.
If not, jump from a battery that you know is good, from a car.  If still nothing, the starter is bad.  If good, then the mower battery is weak.  

Step 2.
If the starter and battery are good, you will need to trace the entire circuit from the starter to the battery.   The solenoid, switches the battery power to the starter, when power from the key switch is sent to the small terminal on the solenoid. To test the solenoid, first make sure that you have power at its large terminal which comes from the battery. Then jump power from that terminal or the battery positive post, to its small terminal. You should hear a click and the other large terminal that feeds the starter should be energized. If not, then the solenoid is bad. If good, then continue tracing the power through the key switch to the battery until you find the break in the power path.   All testing can be done with a 12 volt light or a voltmeter.  Most equipment has safety switches in  the seat and on the blade engagement lever. Check them by temporarily bypassing with a small jumper wire.

Let me know how you make out.
Michael