What Happens if a Mower Deck Is Higher in the Front?

What Can Happen

• Mower blades cut through grass by spinning quickly. To make cutting more efficient, the blades need to tilt slightly downward. This will ensure an even-looking cut. If the blade is angled upward, it won’t slice efficiently through the grass and will produce a rough-looking cut. If the mower deck is too high in the front, the back of the blade may hit an object, such as a rock, that it would otherwise have missed. This could potentially damage the blade, the mandrel pulley or the deck.

Mower Deck Stabilizers

• Mower decks use stabilizing rods to keep them at a fixed angle in relation to the engine and the rest of the lawn mower. These stabilizing rods secure the deck from back to front and from side to side. At the ends of these stabilizing rods are a series of bolts, which, when tightened or loosened, adjust the angles of the deck. These angles need to be measured with a tape measure from the ground up to ensure the deck is at a proper angle.

Measuring Front to Back

• The angle of the deck pointing front to back is the most important angle for cutting. When the deck is lower in front, it will be properly stabilized, and the blades will spin smoothly around the shaft. When measuring the height of the deck, park the mower on a flat, concrete surface to get a more accurate reading. Always position the blades so they are pointing front to back as well. Measure from the blade tip to the ground, and make sure the cutting deck is at least 1/8 inch lower in front.

Other Causes of an Uneven Deck

• The mower deck appears higher in the front or back when the tire pressure is uneven. If the pressure in the rear tires is lower than those in the front, the mowing deck will appear uneven. Always park the mower on a flat surface and check the pressure reading of all four tires before making any mower deck adjustments. Most mower tires stamp the required pressure readings on the sidewall of the tire. Either inflate or deflate each tire as necessary.