106-2175 Idler Pulley Replacement 132-9420, Flat Idler Pulley Compatible with Toro Timecutter SS5000 SS4235 MX5060, Fits 42 & 50 inch Deck Zero Turn Mowers, Replaces Rotary 12901 (1 Pack)

What It Is

This is a flat idler pulley (part 106-2175, replacing 132-9420) that guides and tensions the deck belt on select Toro TimeCutter zero-turn mowers with 42-inch or 50-inch cutting decks. It’s a direct replacement for the OEM pulley, used to reduce belt wear and maintain proper blade engagement.

Fitment & Compatibility

Check your deck size first – this pulley fits Toro TimeCutter models with 42-inch (e.g., SS4235) or 50-inch (e.g., SS5000, MX5060) decks. It does not fit 54-inch or 60-inch decks.

OEM cross-reference: Replaces Toro part numbers 106-2175 and 132-9420, plus Rotary 12901. Confirm your mower’s original part number before buying.

Measurements: Flat idler pulley – outer diameter ~4 inches, inner bearing bore ~5/8 inch. If your old pulley has a different bore or diameter, this won’t fit.

Model list (not exhaustive): Toro TimeCutter SS4235, SS5000, MX5060, and some SS4225/SS5010 variants. Always verify with your mower’s model number (under seat or on frame).

Key Things to Know

• Build quality: Metal pulley with sealed ball bearings – holds up well under normal use, but bearings can fail if the belt is overtightened or debris gets in.
• Installation: Simple swap – remove the deck belt, unbolt the old pulley (usually a 5/16” or 3/8” bolt), install the new one, and re-tension the belt. No special tools needed.
• Common gotcha: The flat pulley face must align perfectly with the belt path. If your old pulley was a grooved (v-belt) type, this flat version won’t work.
• Wear indicator: If the pulley wobbles or makes a grinding noise, replace immediately – a seized pulley can snap the deck belt or damage the spindle.

Should You Buy It

If you own a Toro TimeCutter with a 42” or 50” deck and need a reliable, affordable replacement for a worn or noisy flat idler pulley, this is a solid choice. It’s a direct OEM-style fit, easy to install, and well-reviewed for durability. Skip it if your deck uses a grooved pulley or a different bore size.