Most problems of Toro mowers are related to the engine starting or running improperly and are easy to troubleshoot. A thorough check of several basic engine parts can usually isolate the problem quickly. Regular maintenance of your Toro mower will reduce the chance of a problem.
If your Toro mower is difficult to start or will not start, first make sure the on/off switch is on, the fuel switch is on and the choke is in the proper position.
Gas that has been pumped for more than 30 days begins to deteriorate and lose efficiency. If the gas is old, drain the tank and refill it with fresh gas.
A clogged oil filter reduces airflow to the engine, which affects the engine’s starting ability. Clean or change the air filter.
A dirty or broken spark plug will not produce enough sparks to ignite the engine. Replace the spark plug.
A battery with little or no charge will not generate enough energy to start the engine. Charge or replace the battery.
Dies After Starting
When your Toro mower starts but dies soon after, the problem could be caused by water in the fuel tank, carburetor or hoses. Drain the gas from the tank, carburetor and hoses. Let it dry and refill with fresh gas.
An air leak around the intake or carburetor mounting area, or around the built-in primer bulb interferes with the flow of fuel in the engine. Replace worn or broken gaskets on the intake or carburetor, and replace defective primer bulbs.
If the fuel cap is clogged and not venting properly, fuel will not flow from the tank to the carburetor and the engine will stall. Clean the vents on the fuel cap.
If the problem only occurs when the engine is cold, check that the choke or built-in primer bulb is operating correctly. Repair or replace defective parts.
Dies When Hot
A Toro mower will die if the engine develops vapor lock caused by gas vapor bubbles in the fuel line or carburetor when the engine gets hot. Move the fuel line away from the source of heat and install an in-line filter close to the carburetor so the vapor will disperse before it enters the carburetor.
Other causes include a defective ignition component or condenser, or trash in the cooling fins. Replace defective parts and clean cooling fins.
Runs Rough or Surges
A worn or broken spark plug, or a clogged air filter can cause your Toro mower to run rough or surge once it is started. Replace defective spark plugs, and clean or replace dirty air filters.
If the carburetor or valves are adjusted improperly, your Toro mower will run rough. Adjust the settings on the carburetor and valves according to the directions in the manual for your mower.
Water or debris in the fuel system or the incorrect fuel mix causes your Toro mower to surge while running. Drain and clean the tank, carburetor and hoses. Then, add fresh gas.
An improperly adjusted or defective governor can cause your Toro mower to surge. Adjust the governor according to the instructions in the manual for your mower or replace the governor.
If your Toro mower lacks power, the valves may need to be cleaned or it may be time for a tune-up. Clean the valves; clean or replace the air and fuel; replace the spark plugs; replace the oil filter and change the oil.