How to Test a Condenser on a Lawnmower

Move your lawnmower to level ground and disconnect the spark plug with a wrench. If your lawnmower has a brake system, set it so that the mower won’t move while you work on it.

Disconnect the starter from your lawnmower's engine. Since manufacturers use different methods for attaching their starters, follow your lawnmower’s operating instructions for disconnecting the starter.

Locate the condenser, which should be connected to the starter’s breaker points. Use a small socket set or screwdriver to carefully remove the hardware and wire connections that hold it in place.

Place the condenser on a piece of wood or another insulated surface. A metal surface could cause reading errors.

Touch the red lead point onto the condenser’s “positive” point and the black lead onto the condenser’s metal casing. Hold them in place for 20 seconds. If the multimeter’s needle or reading doesn’t change to a positive indication, the condenser may have shorted out.

Turn the multimeter to the voltage reading setting at a range just above the condenser’s rating, which can be found printed on its case. For example, if the condenser’s range is 400 volts, set the meter to read above that amount.

Place the red and black leads onto the condenser’s positive and negative connecting points, respectively. If the meter does not reach the condenser’s limit, then it may have burnt out.