731-2363 Lawn Mower Mulch Plug Fits CUB Cadet MTD 42" Troy Bilt Pony, Bronco, Replaces 190-116 7311643A GW-7311643A 2150 LT1042 1600 2155 2130 LT1040 2135 2166

What It Is

The 731-2363 is a mulch plug that blocks the side discharge chute on 42-inch cutting decks, forcing grass clippings to circulate and recut into fine mulch. It’s designed for Cub Cadet, MTD, and Troy-Bilt riding mowers, including popular Pony and Bronco models.

Fitment & Compatibility

Before buying, confirm your deck is a 42-inch stamped steel MTD-style deck (common on Cub Cadet LT1000/2000 series, Troy-Bilt Pony/Bronco, and MTD Yard Machines). The plug measures roughly 8.5 x 4.5 inches and uses two slots to slide into the deck’s discharge opening. It replaces OEM part numbers 190-116, 7311643A, and GW-7311643A. It will NOT fit 46-inch or 54-inch decks, or any fabricated/fab decks. Check your mower’s model number (e.g., LT1042, 2150, 2135) for compatibility—most 42-inch MTD/Cub/Troy-Bilt riders from the early 2000s onward are a direct fit.

Key Things to Buy

• Quality: OEM-grade plastic, but some users report the tabs can crack if overtightened or forced. Inspect for flash or burrs before installing.
• Installation: Simple—slide into the discharge opening until it clicks. No tools needed. If it’s tight, a light sanding on the edges helps.
• Common Gotcha: Make sure your mower’s blade is a mulching blade (or at least has a high-lift design). A standard bagging blade won’t chop clippings fine enough, leaving clumps.
• Missing Hardware: Some aftermarket versions lack the rubber gasket. This plug doesn’t require one, but if your deck has a rubber flap, remove it first for a flush fit.

Should You Buy It

If you own a 42-inch Cub Cadet, MTD, or Troy-Bilt rider and want to convert from side-discharge to mulching without buying a full kit, this plug is a cheap, direct fix. It’s best for homeowners cutting dry, short grass on flat lawns. Avoid it if you have a different deck size, a non-MTD brand, or need a full mulching kit with baffles and special blades.