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HomeRepair HelpSimplicity RepairSimplicity Lawn mower starts then stalls Repair
Simplicity Lawn mower starts then stalls
If your Simplicity lawn mower starts then stalls, the problem is usually in the fuel system, with a clogged carburetor at the top of the list. Old gas can leave sticky deposits inside the carburetor, so a lawn mower starts then dies, runs then shuts off, or only runs for a few seconds because fuel flow is restricted. Try cleaning the carburetor with carburetor cleaner first. If that does not fix it, a carburetor repair kit or a complete carburetor replacement may be needed. Next, check the fuel cap vent. A blocked fuel cap can create vapor lock, stopping fuel from reaching the carburetor and causing the mower starts and then stops symptom. Old or bad gasoline can cause the same trouble, so draining stale fuel is often part of the repair. If the fuel system checks out, inspect the spark plug for wear, carbon buildup, or a weak spark, and confirm spark with a spark plug tester. For the exact Simplicity carburetor, fuel cap, spark plug, or other replacement part that fits your mower, enter your model number on RepairClinic.com.
01 - Simplicity 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 stall. 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 - Simplicity 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 stall. 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 - Simplicity Fuel Cap
As fuel is consumed by the engine, the level in the fuel tank lowers. To make up for this, the fuel cap uses a small vent to allow air to enter the tank. If the fuel cap vent is clogged, air won’t be able to enter the tank and a vacuum or “vapor lock” will occur. This stops the flow of fuel to the carburetor causing the engine to stall. To determine if the fuel cap vent is clogged, try slightly loosening the cap and then starting the engine. If loosening the fuel cap allows the engine to stay running it is likely clogged and will need to be replaced.
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04 - Old or Bad Gasoline
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 stall. 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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05 - Simplicity 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.
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Frequently Asked Questions
Why does my Simplicity lawn mower starts then stalls after a few seconds?
How do I tell if the carburetor is causing my Simplicity mower to start and then die?
Can a bad fuel cap make a Simplicity lawn mower runs then shuts off?
My Simplicity lawn mower has spark but starts then stalls. Should I still check the spark plug?
How do I find the right carburetor, carburetor repair kit, fuel cap, or spark plug for my Simplicity mower?
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