How to Fix a Lawn Mower That Won't Start

Any Mower

• 1

  Spray carburetor cleaner into the carburetor. Listen for a popping noise. Proceed to Step 2 if you hear popping. Proceed to Step 3 if there is no popping.

• 2

  Drain the old gas out of the mower. Replace the old gas with fresh gas. Put an additive called dry gas into the new gas to remove water in the gas or motor.

• 3

  Remove the cover from the air filter. Unscrew the holding screw to gain access to the filter. Remove the filter and replace it. Replace the cover and holding screw. Tighten the screw down.

• 4

  Pull the wire from the spark plug. Attach the spark plug socket to the socket wrench. Dislodge the spark plug with the wrench. Unscrew the spark plug and remove it.

• 5

  Examine the spark plug for discoloration or debris at the tip. Any discoloration indicates replacement of the spark plug is required. Screw in the fresh plug and tighten into place. Attach the wire.

• 6

  Start the mower. If the mower doesn't start, proceed to Step 7.

• 7

  Lift the front end of the mower into the air to expose the blade. Examine the blade and shaft to ensure they are not bent or broken. If the shaft is bent or broken, professional repair is required at this point. If the blade is damaged, proceed to Step 8.

• 8

  Unscrew the center bolt holding the blade with the socket wrench. Remove the bolt, then the blade. Remove any debris around the blade underneath the chassis. Replace the blade.

Riding Mowers

• 9

  Use the information above to test basic parts for replacement. Proceed to Step 2 here if all other methods fail.

• 10

  Test the starter. Attach one negative end of the jumper cable to the negative terminal of the mower's battery. Attach the other negative end to a metal piece on the mower. Attach a positive end to the positive battery terminal and the other positive end to the starter positive terminal.

• 11

  Start the mower. Replace the starter if the mower fails to start.