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HomeRepair HelpLawn Boy RepairLawn Boy Lawn mower starts then stalls Repair
Lawn Boy Lawn mower starts then stalls
If your Lawn Boy lawn mower starts then stalls, the problem is usually fuel-related, and the carburetor is the first place to check. Old gasoline can leave sticky deposits that clog the carburetor, so a Lawn Boy lawn mower starts then dies or only runs for a few seconds when fuel can no longer move properly through the engine. Try cleaning the carburetor with carburetor cleaner first. If that does not fix it, a carburetor repair kit or a full carburetor replacement is often the next step. The next likely cause is a clogged fuel cap vent. When the vent cannot let air into the tank, a vacuum forms and fuel flow to the carburetor slows or stops, which makes the mower starts and then stops. Slightly loosening the fuel cap can help confirm that issue. After that, check for stale or bad gas, since contaminated fuel can lead to the same stalling symptom. A worn or fouled spark plug is also worth testing with a spark plug tester and replacing if the spark is weak or missing. Enter your Lawn Boy model number on RepairClinic.com to find the exact replacement part for your mower.
01 - Lawn Boy 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 - Lawn Boy 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 - Lawn Boy 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 - Lawn Boy 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
Frequently Asked Questions
Why does my Lawn Boy lawn mower start then stall after a few seconds?
How do I know if the fuel cap is making my Lawn Boy mower starts then dies problem happen?
Can old gas cause a Lawn Boy lawn mower to start and then stop?
If my Lawn Boy mower has spark but only runs for a few seconds, should I still check the spark plug?
How do I find the right Lawn Boy carburetor, carburetor repair kit, fuel cap, or spark plug for my mower?
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