Some people see mowing as a chore while others may enjoy the time outside, but few relish the idea of getting ready to mow the yard only to discover that the lawn tractor will not start. Most people who mow on a regular basis have at some time experienced problems trying to start the engine. This is especially true in the spring after the mower has been sitting for a season. Find some of the most common reasons why a lawn mower will not start as well as corrective actions that may help to avoid added frustration and costly repair bills.
It is helpful to attempt to try to start the mower a couple of days before the planned first mow of the season so that the lawn tractor will be as ready as the rider when planned.
What to do if a Lawn Mower Will Not Start
Although there are many reasons that would prevent a lawn mower from starting, several are fairly simple and easy to fix. Many manufacturers recommend emptying the gas tank at the end of the mowing season, so it is wise to check the fuel tank first. Checking oil level, tire pressure, and other preventive maintenance before starting the engine is also a wise move.
If the fuel level is adequate, the next step would be to check to see that the engine is properly “choked” per the owner’s manual. Some models may have a separate lever for the choke while other models may have the choke built in where the speed is adjusted. Most mowers have safety features that prevent the mower from being started if someone is not sitting on the seat, the clutch or brake pedal is not depressed, or if the blade is in the engaged position.
If the engine simply will not start after trying numerous times, the engine may be flooded. Take a break and wait for several minutes before attempting to re-start it.
A bad spark plug is another common problem causing the engine not to start. Changing a spark plug is rather simple, provided the right tools and the correct size of spark plug are available. Ensure that the right size is purchased by:
- Bringing the old one to the store or
- Looking in the owner’s manual for the correct size of spark plug or
- Writing down the identifying letters and numbers on the old spark plug
Sockets that will remove a spark plug are deeper than regular-sized sockets. Some stores have loaner tools for use. If purchasing a socket wrench, it may help to purchase the spark plug and ensure that the socket properly fits the spark plug before leaving the store.
The Engine Clicks but Will not Start
If the engine clicks but will not start, the battery is often to blame. To find the battery on a riding lawn mower:
- The battery may be readily visible
- The operator may need to lift the hood
- The battery may be located under the seat
- Check the owner’s manual for the battery location
Check to see that the wires are properly and securely connected and that the terminals are clean. If they are, the battery may need to be recharged or replaced. Bring the old battery to the store if replacing it. This will help to ensure that the correct style is selected as well as providing for proper disposal of the old battery and lessening the charge at most stores.
Battery & Spark Plug are Good but Engine Still Won’t Turn Over
If the lawn mower still does not start, the problem may be with the fuel, especially if it was left in the mower over the winter. If the fuel appears dirty or contains water, it may help to drain the fuel tank and replace with fresh gasoline. The fuel filter may also need to be replaced. A pair of pliers is usually needed in order to loosen the connector for the fuel filter and open the gas line.
A dirty air filter may also cause a lawn mower not to start or to be difficult to start. Some air filters are easy to find at parts stores while others may need to be special ordered. The owner’s manual may list the part number for the air filter. If not, it helps to have the model number and serial number of the engine to help determine that the correct size is ordered. Some people have success blowing out a dirty air filter with an air compressor.
Other reasons that may cause a lawn mower not to start include, but are not limited to:
- Damaged or loose wiring
- Problems with the carburetor
- Maladjusted engine valves
- A blown fuse
- The ignition switch is faulty
- Solenoid or starter is faulty
Troubleshooting Tips May Save Costly Lawn Mower Repair Bills
A lawn mower that will not start is a common problem, but knowing a few simple, low-cost repair tips can save time and money. Sometimes the process is a bit of trial and error, but with a systematic approach, the owner may have quicker success with less headaches and less stress.