The first clue that you have a spindle problem with your riding mower may be an uneven or stepped appearance in the grass after you've mowed. If you notice either of these conditions, check out the spindles to see whether one or more of them are bent, broken or loose. If you find that they are, it's time to pull out your tools and replace the funky spindle with a new one.

• Spindle Basics

The spindle on a riding mower is the post to which the blade attaches and around which it spins when the machine is in action. A riding mower may have one or more spindles, depending on the size of the mower and the way it is manufactured. You may have a problem with one or more spindles at the same time. Spindles may deteriorate from simple wear and tear over the years or may bend or break suddenly when you collide with a significant foreign object like a stump, large rock or cement walkway during mowing.

• Safety Precautions

Before you get to work replacing the spindle in your riding mower, you need to take several steps to ensure your safety. Park the mower on a level surface, set the parking brake and remove the keys from the ignition. Remove the spark plug wire from the spark plug as well to prevent accidental ignition. Wear a pair of heavy-duty work gloves to protect your hands and fingers from the sharp edges on the mower and blades.

• Spindle Removal

To access the spindle easily, remove the deck from the mower. Remove the blade and pulley from the spindle and lay them aside. When a spindle has been in place on the mower for a number of years, it may be difficult to remove. If the bolts that hold the spindle assembly in place seem stuck in place, apply a penetrating oil and allow it to soak for 30 minutes or so before attempting to remove the bolts again. Unscrew the bolts, remove the spindle assembly and pull the spindle from the center of the unit.

• Spindle Replacement

Since removing the old spindle assembly is often the most difficult part of the replacement process, reassembly of the unit should be a breeze. Insert the new spindle into the center of the spindle housing. Reattach the spindle housing to the mower deck with the bolts that you removed previously. Reinstall the blade and pulley and tighten them into place. Consult your owner's manual to ensure that you've tightened the flange nut that holds the pulley in place to the proper specifications. The suggested torque for the flange nut is often between 55 and 65 foot-pounds, however, your model may require a slightly higher or lower figure.

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