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What should I do when my lawn and garden engine is unable to start?

Problem

There is nothing more frustrating than when your mower, tiller or snow blower won’t start. The more you pull on the starting cord or push the button and hear the motor turn over without starting, the more discouraging it becomes.

Causes

Like any gas-powered engine, your lawn and garden machine needs three things to start and run properly:

  • Air
  • Fuel
  • Spark to ignite the air/fuel mixture

If any of these necessary elements aren’t supplied at the proper time and in the proper amount, the engine won’t start.

Close up of a lawn mover cutting grass in what looks to be someone's yard

Symptoms:

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Dirty or Clogged Air Filter

Before the incoming air enters the carburetor, it passes through an air filter to remove dust and dirt. When the filter is doing its job, it may get clogged up with debris removed from the air and not allow a sufficient amount of air into the carburetor and prevent the engine from starting.

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Dirty or Clogged Fuel Filter

The fuel filter keeps dirt in the fuel from getting into the carburetor, and like the air filter, may eventually become clogged and prevent a sufficient amount of fuel from passing into the combustion chamber, preventing your engine from starting.

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Faulty Spark Plug

A spark plug fouled by fuel, carbon, dirt or oil on the electrodes may not produce a spark strong enough to ignite the air/fuel mixture and start your engine.

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Bad Gas

Ethanol-based gas can go stale in 30 days or less. As gas breaks down, gum and varnish are formed that can clog fuel lines and carburetor jets making your engine impossible to start.

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Gas Cap

Most gas caps will have an air vent that allows air to enter the fuel tank as the fuel is used. Sometimes this vent gets clogged with debris and will restrict fuel flow into the carburetor. Other options include adding a fuel stabilizer to your tank or using canned fuel that contains no ethanol.

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Fuel Lines

Cracked or collapsed fuel lines can prevent engine from getting fuel and starting.

Solutions

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Change air filter if it’s clogged or dirty.

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Replace fouled or dirty spark plug.

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Unclog or replace gas cap if air vent is blocked.

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Replace dirty or clogged fuel filter.

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Replace old gas with fresh gas (properly dispose of old gas).

If none of these suggestions resolves your starting issues, then it’s time to call on a professional mechanic who specializes in small engines. 

Learn more about lawn & garden maintenance products, find your part, or find where to buy your part today.

The content contained in this article is for informational purposes only and should not be used in lieu of seeking professional advice from a certified technician or mechanic. We encourage you to consult with a certified technician or mechanic if you have specific questions or concerns relating to any of the topics covered herein. Under no circumstances will we be liable for any loss or damage caused by your reliance on any content.

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