Trouble Starting a Toro Lawn Mower

Diagnosing the Problem Area

• For a Toro lawn mower to start and keep the internal combustion running, it needs three things: spark, fuel and air. If any of these three crucial elements are missing, even in small quantities, the engine will not work. To find the problem, first locate the missing element of fuel, spark or air, which will help point you to the malfunctioning part and help you locate the direct source of that lost element within the related engine system.

Troubleshooting the Problem System

• Locating the problem can seem difficult at first, but most symptoms typically point to the larger problem. Hard starts, in which the engine starts then promptly dies or starts and runs for a few minutes before dying, are problems that likely reside in the fuel system. Poor performance, sluggish engines and difficult starting can occur in a dirty air system. However, more serious starting problems, like no starts or backfiring, may reside in the electrical system.

Basic Service

• Diagnosing and troubleshooting a part can take up to several hours, so to help ease the labor, look for common small engine problems while performing a basic cleaning and tune-up on the mower. Check and clean the air filter, the area around the carburetor, the fins and area around the cylinder. Open up the muffler, and check and clean the spark arrestor screen and exhaust port. Clean out the gas tank, pull the old fuel filter out and replace the filter and the fuel hoses. Replace the spark plug and check all of the electrical wiring for loose or damaged connections.

Fixing It

• Sometimes problems exist deeper in the engine and can vary widely with symptoms. These problems, like gas, air or oil leaks, loose gasket seals, dirty carburetors and similar problems will take extensive troubleshooting and repair work. If, after performing basic cleaning and servicing, the problem still persists, perform further tests on the carburetor, crankcase and ignition module. However, these tests can be difficult, and if done poorly, can cause injury, electrocution and total engine failure. Leave technical repairs to a service professional.