How to Adjust a Belt Tensioner on a Toro Walk-Behind

Toro walk-behind mowers use a rubber drive belt to propel the wheels. The mower has a tensioner adjustment mechanism to ensure the belt remains tight on the drive wheel and pulley assembly. A loose belt will not propel the mower effectively and may wear out prematurely from slipping on the metal drive wheel. Adjusting tension on the belt takes only a few minutes.

Step 1

Shut off the Toro and wait for the engine to cool. Pull the spark plug wire off the tip of the plug on the engine block.

Step 2

Take out the screws holding the belt guard cover over the drive mechanism. Remove the cover to expose the drive belt and tensioner.

Step 3

Loosen the four handle bracket mounting screws on the tensioner. There are two screws on each side of the bracket surrounding the drive belt.

Step 4

Loosen the screw on each side of the rear height adjuster bracket.

Step 5

Slide both ends of the tensioner mechanism until the belt is taut on the pulley wheels.

Step 6

Tighten all bracket screws with the screwdriver.

Step 7

Engage the drive lever on the Toro. When pressing the center of the belt with your thumb, the belt should give less than 1/2 inch with proper tension.

Step 8

Replace the belt guard cover and secure with the screws.

Step 9

Attach the spark plug wire to the plug tip.

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