Lawnmower Repair: How to Remove the Belt Pulley From the Engine Shaft

Place the lawn mower on a flat, level working area. Set the lawn mower parking brake, and slide cement or wooden blocks in front and behind the rear tires to prevent the lawnmower from shifting while repairing. If the engine is hot, allow adequate time for the engine to cool before servicing or repairing the lawn mower.

Lift the lawnmower seat to gain access to the battery area. Unbolt the battery terminals with a 7/16-inch socket wrench or Phillips head screwdriver. Lift the battery out of the lawnmower to prevent the battery cables from coming in contact with the battery terminals. Pull the spark plug wire off of the spark plug by hand; twist the rubber spark plug boot while pulling at the same time to loosen and remove the boot.

Disconnect the lawnmower cutting deck from the lawn mower frame to gain access to the engine shaft belt pulley. Lawn mower deck removal instructions vary with different models, but specific instructions are located in the owner's operating and service manual.

Loosen the large transaxle pulley with a 7/16-inch socket wrench. The pulley is the largest pulley located in the battery access area under the lawnmower seat. Remove the upper drive belt pulley tension spring with a spring puller tool from the anchor bolt on the left side of the lawnmower, which is the same side as when you are sitting in the seat.

Slip the rear upper belt off of the large transaxle pulley and variable speed pulley, and remove the belt through the battery access area. Unscrew the drive belt guide bolt with a 1/4-inch socket wrench from the variable speed pulley bracket through the battery access area.

Lift the middle drive pulley enough to allow the drive belt to clear the belt guide and slip it off of the engine pulley.

Wrap a strap wrench around the engine crankshaft drive pulley located under the lawn mower frame beneath the engine. Unscrew the crankshaft pulley retaining bolt with a 5/8-inch socket wrench and breaker bar for added leverage. Turn the bolt counterclockwise with one hand while holding the strap wrench firmly with the other.

Slide the crankshaft pulley lock washer and flat washer off of the engine belt pulley by hand. Slide the engine belt pulley off of the crankshaft by hand. Spray the crankshaft and engine pulley mating surfaces with penetrating oil to free rusted and stuck parts. Tap on each side of the engine pulley slightly with a ball peen hammer to loosen rusted and stubborn pulleys.