How to Troubleshoot an Exmark Quest Zero-Turn Mower

Examine the fuel level in the Exmark Quest Zero-Turn mower's gas tank and ensure you have adequate gas. Refill the tank if necessary.

Burn off any old gas that has been sitting in the tank for months, if applicable. Refrain from adding fresh gas until the old gas is disposed of, then refill the tank entirely and add a splash of gas additive to help the Exmark mower run smoothly during its first start. Gas additives act as corrosion inhibitors, lubricants or both, and can ensure your Exmark mower runs properly after it has been sitting for a long time.

Open the Exmark Quest Zero-Turn mower's engine cover and check your spark plug if the mower still won't run. Ensure the black plug wire is still connected to the spark plug at the side of the engine assembly.

Disconnect the Exmark mower's spark plug and replace it if it is old and potentially faulty. Reconnect the plug wire to the new spark plug.

Follow the plug wire to the back of the Exmark Quest Zero-Turn mower's Kawasaki engine assembly. It will lead to the magnetic coil. Behind the magnetic coil is the flywheel, and the space created between the two parts is the air gap. Measure the air gap and see if it is between 0.010 and 0.015 of an inch in width. This must be a precise measurement.

Adjust the magnetic coil by loosening its bolts with a socket wrench. Incrementally move the magnetic coil to accommodate the necessary specifications of the air gap, then remeasure the air gap.