917-05121 Electric PTO Mower Clutch 717-05121 Fits for Cub Cadet/MTD/Craftsman 717-04376 917-04376 for Troy Bilt White Outdoor RZT-42 2010 After (2010-2012) RZT-S42(2013 and 2014)

What It Is

This is an electric PTO (power take-off) clutch that engages and disengages the mower blades on zero-turn and lawn tractors. Designed for Cub Cadet, MTD, Craftsman, Troy-Bilt, and White Outdoor models, it’s a direct replacement for OEM part numbers 717-04376, 917-04376, 717-05121, and 917-05121.

Fitment & Compatibility

Before buying, confirm these three things:

• Model & year: This clutch fits Cub Cadet RZT-42 (2010–2012) and RZT-S42 (2013–2014). Also fits many MTD, Craftsman, Troy-Bilt, and White Outdoor zero-turns from 2010 onward. Check your machine’s model and serial number against the listed compatibility.
• Deck size: Works with 42-inch and 50-inch decks on compatible tractors. Measure your existing clutch’s shaft diameter (typically 1 inch) and bolt pattern (3-bolt, 4.25-inch spacing) to be sure.
• OEM vs aftermarket: This is an aftermarket replacement. It’s functionally identical to OEM but may have slight differences in wire length or connector style. Compare your old clutch’s connector shape and wire gauge.

Key Things to Know

• Installation difficulty: Moderate. You’ll need basic hand tools (socket set, torque wrench) and a jack or lift to access the clutch. Expect 1–2 hours if you’re handy.
• Common gotcha: The clutch may come with a loose or missing retaining ring. Check and secure it before mounting. Also, the air gap (typically 0.010–0.015 inch) often needs adjustment after installation—use a feeler gauge.
• Quality: Rated 4.2/5 from 28 reviews. Most users report reliable engagement and smooth operation, but a few mention premature bearing noise after 1–2 seasons. Consider greasing the bearing at install.
• Warranty: Usually 1-year limited. Keep your receipt and test the clutch immediately—defective units are rare but do happen.

Should You Buy It

If your OEM clutch has failed on a 2010–2014 Cub Cadet, MTD, or Craftsman zero-turn, this is a solid, cost-effective replacement. It’s not a premium brand, but it gets the job done for most homeowners and light commercial users. Skip it if you need a heavy-duty clutch for daily commercial mowing—look for a higher-rated aftermarket or OEM part.