131494 Idler Pulley Craftsman Replaces 165888 Idler Pulley Craftsman Pulley Idler Flat 165888, 165888 Pulley, 532165888, 532173437, 173437 Pulley, 532173438 Idler Pulley Craftsman, 597025001

What It Is

The 131494 idler pulley is a flat pulley that guides and tensions the drive belt on Craftsman lawn mower decks, typically used on 42- to 54-inch cutting decks with manual or automatic belt tensioning systems.

Fitment & Compatibility

• Direct OEM replacements: This part supersedes Craftsman 165888, 532165888, 532173437, 173437, 532173438, and 597025001. If your mower lists any of those numbers, this pulley fits.
• Cross-brand fit: Works on many Craftsman, Husqvarna, Poulan, and AYP (American Yard Products) mowers with the same deck pattern. Always verify with your mower’s model number (found under the seat or on the frame).
• Physical specs: Measures 3.5 inches outer diameter, 0.5-inch bore (fits a 1/2-inch shaft), and uses a 3/8-inch wide flat belt. Measure your existing pulley’s diameter and shaft hole before ordering.
• Check deck size: Common on 42-inch, 46-inch, 48-inch, and 54-inch decks. If your deck uses a 3/8-inch flat belt with a spring-loaded or fixed idler arm, this is likely correct.
• Aftermarket note: This is an aftermarket part, not OEM Craftsman. Quality is generally good, but inspect for smooth bearing rotation and no wobble on the shaft before installation.

Key Things to Know

• Quality: Solid build with sealed ball bearings—no greasing needed. Most users report 2-3 seasons of regular mowing before replacement.
• Installation difficulty: Easy (5-10 minutes). You’ll need a wrench or socket to remove the mounting bolt, then transfer the old pulley’s spacer or washer to the new one. Some decks require removing the belt first.
• Common gotcha: The flat pulley surface (not grooved) is critical—don’t confuse it with a V-groove idler. If your belt is rounded or V-shaped, this won’t work.
• Bearing noise: A slight whir is normal; grinding or roughness means a defective bearing. Spin it by hand before installing—replace if it feels gritty.

Should You Buy It

Buy this pulley if your Craftsman or compatible mower deck uses a 3/8-inch flat belt and you need a budget-friendly direct replacement for the 165888 or 173437 series. It’s ideal for DIY repairs on mid-sized residential decks, but if your mower is a commercial model or has oddball belt widths, measure twice or stick with OEM.