How to Modify a Mulch Mower Deck

Turn off your lawnmower and let it cool down fully.

Open the hood over your mower's engine and disconnect the spark plug ignition wire found on the side of the engine's assembly. The ignition wire plugs into the back of the spark plug.

Put on gloves and look under the mower to find the discharge shoot that sits parallel to the lawn mower's bottom. Measure the forward-most part of the blade from its tip to the ground. Also, measure the height of the rearmost part of the blade from its tip downward.

Loosen the lawn mower's hex nut using a wrench. This nut will be just below the suspension arm on the mower's bottom. The front and rear of the deck will raise up if you tighten the nut. Conversely, the deck will lower if you loosen the nut.

Rotate the mower's perpendicular blades in order to adjust the mulching deck from side to side.

Locate the hangar bracket on the left of the bottom of the lawn mower. It will be located beside the perpendicular blades. Loosen the hex bolt located on the hangar bracket using your wrench.

Find the lawnmower's adjustment gear beside the hex bolt. Loosen it with your wrench in order to lower the deck from side to side. Tighten it instead in order to raise the deck from side to side.

Measure both the mower's perpendicular blades from their tips to the ground and ensure they are equal. Alter the adjustment gear further as necessary in order to balance the perpendicular blades.

Use your wrench to tighten the hex bolt once you are finished with the adjustment gear and the blades are correctly set.

Reconnect the lawnmower's ignition wire to the spark plug and close the hood.