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HomeRepair HelpAriens RepairAriens Lawn mower runs rough Repair
Ariens Lawn mower runs rough
If your Ariens lawn mower runs rough, sputters, or the engine runs unevenly after starting, the most common cause is a clogged carburetor. Old fuel can leave behind a sticky varnish that restricts fuel flow and makes the mower engine surge or run rough. Start by cleaning the carburetor with carburetor cleaner. If that does not restore smooth operation, the carburetor may need to be rebuilt with a carburetor repair kit or replaced outright. Next, check the spark plug for carbon buildup, cracked porcelain, or a damaged electrode, and use a spark plug tester to confirm it is producing a strong spark while cranking. A weak or failed spark plug can also cause an Ariens lawn mower to run rough. Another possible cause is a clogged fuel filter, especially if old gas has been sitting in the tank, since restricted fuel delivery can lead to sputtering and uneven engine performance. Drain stale fuel if needed and replace the fuel filter. Enter your model number on RepairClinic.com to find the exact Ariens carburetor, spark plug, fuel filter, or other replacement part that fits your mower.
01 - Ariens 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 - Ariens 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 - Ariens 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 - Ariens 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 Ariens lawn mower run rough after it starts?
How do I know if the carburetor is causing my Ariens mower engine to run unevenly?
Can a bad spark plug make an Ariens lawn mower run rough?
What should I check first if my Ariens lawn mower is sputtering or surging?
How do I find the right carburetor, spark plug, or fuel filter for my Ariens lawn mower?
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