What causes a lawn mower to not start?

Other possible causes include: Loose, Dirty or Disconnected Spark Plug in Your Lawn Mower: Check it out, clean off debris, re-connect and tighten. Dirty Air Filter: Clean or replace. Fuel Not Reaching the Engine: Tap the side of the carburetor to help the flow of gas.

Why is my lawn mower turning over but not starting?

The most common reason for a riding mower cranking over but not starting, is bad gas, but other possible reasons include: Gas Valve Off. No Gas. Choke Fault.

What would cause my mower to not start?

First, see these 7 simple reasons your mower might not start.

  • 1) Out of Gas. It sounds crazy, but it happens! …
  • 2) Stale Gas Leads to Clogged Carburetor. How long ago did you fill up your gas tank? …
  • 3) Clogged Fuel Filter. …
  • 4) Dead battery. …
  • 5) Bad Starter Solenoid. …
  • 6) Disconnected or Dirty Spark Plug. …
  • 7) Dirty Air Filter.
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How do you troubleshoot a lawnmower?

If you run into problems getting your lawnmower ready for spring, try the following:

  1. Use fresh gas. Old gasoline can cause starting difficulties. …
  2. Check the spark plug. …
  3. Use the choke. …
  4. Prime the mower. …
  5. Check the air filter. …
  6. Check the cables. …
  7. Check for water in the fuel tank.
  8. Clear the starter cord of blockages.

Why has my lawn mower stopped working?

The most common cause of a lawnmower that won’t start is a faulty spark plug. First, try cleaning any debris off the plug – if this doesn’t work, it will need to be replaced. The problem could be caused by something as simple as a clogged air filter.

Can a dirty air filter cause a lawn mower not to start?


Your lawn mower’s air filter guards the carburetor and engine from debris like grass clippings and dirt. When the air filter becomes clogged or too dirty, it can prevent the engine from starting.

How do you clean a carburetor on a lawn mower without removing it?

However, you can not spray the carburetor when the engine is off since it cannot do the cleaning without being propelled. All you need to do is to start the engine and spray directly at the center of the carburetor while it is running. Any deposits clogging in the carburetor will easily be removed.

How do you know if the ignition switch is bad on a lawn mower?

To check your ignition switch, you can use an ohmmeter to see if there is any connection between the “S” and “B” terminals. If there isn’t any, the ignition switch is your problem and you will need to replace it to get your mower running properly again.

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How do I know if my lawn mower spark plug is bad?

Here’s How to Know if a Lawn Mower Spark Plug is Bad

  1. You can’t get the engine to fire up at all.
  2. You have to tug extra hard for longer than usual on the rewind.
  3. Your lawn mower loses power while moving.
  4. The gas runs out quicker than it used to.

How do I know if my lawn mower carburetor is bad?

Dirty Carburetor Symptoms

  1. The lawn mower engine has trouble starting.
  2. The engine starts but stalls while you’re cutting the lawn.
  3. The engine runs rough during mowing.
  4. Black smoke is seen coming out of the muffler.
  5. There is a noticeable increase in fuel consumption during normal lawn mower use.

How do you fix a small engine that won’t start?

If the tank has fresh gas and you’ve primed the carburetor and set the choke but it still won’t start, it’s time to remove the spark plug. If the spark plug is wet with gas, it proves the engine is getting fuel. Dry off the plug with compressed air and examine it for signs of carbon buildup or oil deposits.

How do you diagnose a small engine not starting?

  1. Determine why your small engine won’t start by checking your fuel levels, spark plug, carburetor, valve & compression levels and more. …
  2. Stale, untreated gas begins to break down after about a month. …
  3. Check your oil level and appearance every time you use your engine while it is cold.

Why is my electric mower not working?

Reset or replace any defective fuses or breakers in your home. Your electrical outlets may not be working if the lawnmower has tripped a breaker or blown a fuse. You can test the outlet by plugging in a lamp or other small appliance. Your fuses or breakers need attention if the lamp or appliance doesn’t work.

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