How do you check a spark plug on a lawn mower?
Similarly, will a lawn mower start if the spark plug is bad?
A dirty or fouled spark plug can cause your lawn mower to not start. It can also work itself loose, causing issues. If the spark plug appears to be seated correctly but the engine doesn't start, a new one may be in order.
Correspondingly, how do you check a spark plug without a tester?
Why is my lawn mower turning over but not starting?
The most common reason for why your riding mower will turn over but not start is likely due to bad gas or a dirty carburetor. You can usually fix the problem by removing and cleaning out the carburetor and making sure that your gas is fresh. There are carb cleaners you can purchase to help you with this.