731-07486 Lawn Mower Side Chute & 987-02516A Hinged Mulching Plug, Compatible with MTD, Troy Bilt, Craftsman, 21" Deck Chute Lawn Mower/Lawn Tractor, for Troy Bilt TB100, TB105, TB110, TB120

What It Is

This is a two-piece set: a side discharge chute (731-07486) that directs grass clippings out the right side of the deck, and a hinged mulching plug (987-02516A) that blocks the chute opening to recirculate clippings for finer mulching. Designed for 21-inch cutting decks on select MTD, Troy-Bilt, and Craftsman walk-behind mowers and lawn tractors.

Fitment & Compatibility

• Deck size: Only fits 21-inch decks. Measure your deck width before ordering.
• Brands: Compatible with MTD, Troy-Bilt, and Craftsman models that use OEM part numbers 731-07486 (chute) and 987-02516A (plug). Cross-references with 731-07486A, 731-07486B, 987-02516, 987-02516B.
• Specific models: Works on Troy-Bilt TB100, TB105, TB110, TB120 series. Also fits Craftsman 917 series and many MTD 11A/11B/13A models.
• Check: Look for a rectangular chute opening on the right side of your deck (not rear or left). The plug has a hinge that clips into the opening. If your deck has a fixed chute or a different locking tab, this won’t fit.
• OEM vs aftermarket: This is an aftermarket set. OEM versions are identical in fit but often cost more.

Key Things to Know

• Installation difficulty: Easy – no tools needed. The chute snaps on, and the plug hinges into the opening and locks with a tab.
• Quality: Sturdy plastic, but the hinge on the plug can crack if forced closed when debris is jammed. Clean the chute opening before inserting.
• Common gotcha: The mulching plug must be fully seated and locked for the mower to run safely (engine kill switch). If it pops out, check that the deck opening isn’t bent.
• Use case: Switch between side discharge (for tall/wet grass) and mulching (for dry, short clippings) without buying a separate mulching kit.

Should You Buy It

Buy this if you own a compatible 21-inch MTD/Troy-Bilt/Craftsman mower and want a cheap, easy way to switch between side discharge and mulching without modifying your deck. Avoid if your deck has a fixed chute or you need a rear bagger attachment.