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HomeRepair HelpToro Mower RepairToro Lawn mower runs rough Repair
Toro Lawn mower runs rough
If your Toro lawn mower runs rough, sputters, or the engine runs unevenly, the most likely problem is a clogged carburetor caused by old fuel leaving behind sticky deposits. This is the first place to check when a lawn mower runs rough after starting, since restricted fuel flow can make the engine surge, stumble, or hunt at different speeds. Try cleaning the carburetor with carburetor cleaner first. If that does not fix the problem, rebuild it with a carburetor repair kit or replace the carburetor altogether. Next, inspect the spark plug for heavy carbon buildup, a cracked porcelain insulator, or a damaged electrode. A spark plug tester can help confirm whether the plug is producing a strong spark while the engine is cranking. If the plug checks out, look at the fuel filter, since a clogged filter can also starve the engine and cause lawn mower sputtering or uneven running. If old fuel has been sitting in the tank, drain it before replacing parts. Enter your Toro model number on RepairClinic.com to find the exact carburetor, carburetor repair kit, spark plug, or fuel filter for your mower.
01 - Toro Lawn Mower Carburetor
The carburetor might be clogged. A clogged carburetor is most commonly caused by leaving fuel in the lawn mower for a long period of time. Over time, some of the ingredients in the fuel may evaporate, leaving behind a thicker, stickier substance. This sticky fuel can clog up the carburetor and cause the engine to run roughly. If the carburetor is clogged, try cleaning it with carburetor cleaner. If cleaning the carburetor isn’t effective, rebuild or replace the entire carburetor.
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02 - Toro Lawn Mower Carburetor Repair Kit
The carburetor might be clogged. A clogged carburetor is most commonly caused by leaving fuel in the lawn mower for a long period of time. Over time, some of the ingredients in the fuel may evaporate, leaving behind a thicker, stickier substance. This sticky fuel can clog up the carburetor and cause the engine to run roughly. If the carburetor is clogged, try cleaning it with carburetor cleaner. If cleaning the carburetor isn’t effective, rebuild or replace the entire carburetor.
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03 - Toro Lawn Mower Spark Plug
Inspect the spark plug for signs of wear or damage. If the porcelain insulator is cracked, an electrode is burned away or damaged, or there is heavy carbon buildup at the electrode, replace the spark plug. To determine if the spark plug is defective, use a spark plug tester. You should see a strong spark between the tester’s terminals when the engine is cranking. If there is no spark, this indicates that the spark plug is defective and should be replaced.
Highly Likely
04 - Toro Lawn Mower Fuel Filter
The fuel filter might be clogged. A clogged fuel filter is most commonly caused by leaving old fuel in the lawn mower. Over time, some of the ingredients in the fuel may evaporate, leaving behind a thicker, stickier substance. This sticky fuel can clog up the fuel filter and cause the engine to run roughly. If old fuel was left in the lawn mower, drain the old fuel from the fuel tank and replace the fuel filter.
Less Common
Frequently Asked Questions
Why does my Toro lawn mower run rough after it starts?
Can a bad spark plug make my Toro lawn mower run rough?
How do I know if the carburetor on my Toro mower needs cleaning or a carburetor repair kit?
Will a clogged fuel filter cause a Toro lawn mower to sputter or surge?
How do I find the right carburetor, spark plug, or fuel filter for my Toro lawn mower?
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