Route a Riding Mower Deck Belt: Diagram & Repair Tips

The deck belt under a riding mower can seem like a random tangle of rubber if you're not familiar with this type of maintenance. For step-by-step instructions and preparation tips, check out our guide on how to replace the drive belt on a riding lawn mower. But when it's time to route the actual mower deck belt, use the five tips below along with belt diagram for an MTD riding mower above, which highlights the belt in yellow, to make the change:

1. Take a picture of the pulley configuration before removing the old belt.

The above belt diagram for an MTD riding mower is only for a 46" deck belt, if you have a different belt, you may want a different frame of reference. The personalized photo can also help you apply these tips to your particular machine.

2. Loosen the idler pulley rods to remove the old belt, and inspect the new belt for installation.

The new belt should be free of visible cracks, tears or dry rot.

3. Use the pulley indicated in your Operator's Manual when routing the new belt.

If your manual does not indicate which pulley to start with, begin by fitting the belt on the outermost pulley on one side of the deck and work your way across.

4. Follow the owner's manual or your photo of the old belt configuration and carefully route the mower deck belt around each pulley as shown.

5. Do not apply lubricants to the belt; they can cause the rubber to deteriorate and damage the deck belt.

Improperly routing a mower deck belt can damage the belt, and potentially the mower. Using non-original equipment manufactured parts can also cause damage and may wear incorrectly, needing to be replaced more often. Once the belt is installed, run the deck a few times; the mower should be free of any unusual noises or vibrations. If the deck is making more noise than usual, vibrating excessively or smoking, turn off the mower immediately. Allow it to cool down, and then reassess the deck belt and adjust if necessary. To order a new deck belt for your riding mower, enter the parts number found in your Operator's Manual in our Parts Finder on the left, or browse our top-selling mower belts to find what you need.

Fix equipment issues quickly

When you need parts for your walk-behind lawn mower or riding lawn mower, you can use the MTD Genuine Parts Part Finder to find the correct one. Common parts include:
Riding Mower Blades
Riding Mower Belts
Riding Mower Blade Spindles
Riding Mower Tires & Wheels
Oil, Lubricants and Fuel Additives

The MTD Genuine Parts Knowledge Center provides do-it-yourself instructions for performing many basic maintenance items, including replacing cutting blades, drive and deck belts, and engine oil. If you find your machine has a bigger problem, use our service locator to find a qualified MTD service provider in your area.