Riding Mower and Tractor: Mower deck vibrates

If the mower vibrates when you engage the cutting blades, there might be a problem with the blade drive system. Deck vibration can be caused by an unbalanced blade, worn pulley or mandrel, bad blade belt or debris caught inside a pulley. Loose nuts or bolts on the pulleys, mandrels or blades can also cause vibration. Remove the mower deck and re-tighten all fasteners. Check for wear on pulleys, mandrels and blades. Replace any worn or damaged components.

These repairs may help solve your Riding Mower and Tractor problem:

Replace the riding mower mandrel assembly

Mandrel assembly

If a noise comes from the mower deck while the riding mower or lawn tractor is running, or if the mower isn't cutting evenly, you might need to replace the riding mower's mandrel assembly.

For manuals, repair guides, and specific part recommendations, enter your model number.

Replace the riding mower mower blade

For manuals, repair guides, and specific part recommendations, enter your model number.

Replace the riding mower blade belt

Blade belt

The blade belt spins the blades to cut the grass. A worn or broken drive belt won’t spin the cutting blades so your mower won’t cut the grass. Examine the blade belt regularly and replace it if it’s worn or broken.

For manuals, repair guides, and specific part recommendations, enter your model number.

Replace the riding mower deck idler pulley

Deck idler pulley

You might need to replace riding mower deck idler pulley if a noise comes from the mower deck when the riding mower or tractor is running, if the belt is loose, or the belt comes off.

For manuals, repair guides, and specific part recommendations, enter your model number.