5" Split Idler Pulley Fit for BadBoy Bad Boy Maverick MZ Magnum Rambler Diesel Outlaw XP Extreme ZT Elite Avenger Repalces 033-8050-00 5104716YP 5102678YP, Lawn Mower Deck Pulley

What It Is

This is a 5-inch split idler pulley designed to guide and tension the drive belt on Bad Boy zero-turn mower decks. It replaces worn or seized pulleys that cause belt slipping, squealing, or poor cutting performance on models including Maverick, MZ, Magnum, Rambler, Diesel, Outlaw XP, Extreme, ZT Elite, and Avenger.

Fitment & Compatibility

Before buying, confirm your mower uses a 5-inch outside diameter split pulley (measure your old pulley across the flat face). This part cross-references OEM numbers 033-8050-00, 5104716YP, and 5102678YP – check your manual or old pulley for any of these. It fits Bad Boy decks with a 1/2-inch bore and uses a split design that clamps around the spindle shaft (no need to remove the blade or spindle assembly). If your deck uses a solid pulley with a keyway, this split type won’t work. Also verify the pulley’s shoulder height (typically 0.75–1 inch) matches your belt path to avoid belt alignment issues.

Key Things to Know

• Split design simplifies installation – you can replace the pulley without pulling the deck spindle or blade, saving 30–60 minutes of labor.
• Check bearing condition immediately – spin the pulley by hand; it should rotate smoothly with no wobble or grinding. Some aftermarket units have less durable bearings than OEM, so inspect before installing.
• Torque the mounting bolt to spec – typically 20–25 ft-lbs on the split’s clamping bolt. Overtightening can warp the pulley or damage the bearing.
• Common gotcha – the split gap must align with the belt path. If installed backward, the belt can catch on the split edge and wear prematurely.

Should You Buy It

This is a solid budget-friendly replacement for DIY owners who want to avoid a full spindle tear-down. If you have a Bad Boy with a split-pulley deck and are comfortable with basic wrench work, it’s a good value at $27. For commercial operators running daily, consider OEM for longer bearing life – but for occasional residential use, this will perform fine.