Often asked: How To Test A Lawn Tractor Coil?

How do I know if my lawnmower coil is bad?

Replace the original wire with the in-line spark tester, and attempt to start the motor. Watch for the same intensity of a spark that you saw when the mower was cold, If there is little or no spark, the ignition coil is bad and needs replacement.

What causes a lawn mower coil to go bad?

Overheating. The operating temperature of the engine gets to hot and burns the coil out. This is not real common on a small engine as usually the engine will shut down from heat before the coil will fail, but it is possible. Resistance problems.

What causes no spark on lawn mower?

Ignition Module Failure When it does fail, it is usually due to heat caused from improper wiring of the ground wire to battery voltage. If the engine does not produce spark, other areas of the ignition system should be checked before focusing on the ignition module as source of failure (see above).

How many ohms should a ignition coil have?

Most ignition coils should have a primary resistance falling somewhere between 0.4 and 2 ohms; however, refer to your manufacturer’s specifications for the correct reading. If a reading of zero is displayed, that signifies that the ignition coil has shorted internally in the primary windings and needs to be replaced.

Why am I not getting spark from my coil?

Loss of spark is caused by anything that prevents coil voltage from jumping the electrode gap at the end of the spark plug. This includes worn, fouled or damaged spark plugs, bad plug wires or a cracked distributor cap.

Do you need a resistor with a 12 volt coil?

If a 6 volt ignition system is converted to 12 volts and a Delco style 12 volt coil with an internal resistor is installed as part of the conversion, no external resistors are required. The 12 volt battery must be connected so the negative (-) battery terminal is connected to ground.

What happens when ignition coil gets hot?

A damaged coil can short some windings, causing high current but low inductance, so low energy. As it gets hot the energy falloff weakens the spark until the engine quits making noises.