2-Pack Finish Mower Idler Pulley, Replaces King Kutter Part #164090, for RFM Series Finish Mowers,4', 5', 6' Mowers

What It Is

This is a 2-pack of finish mower idler pulleys that replace King Kutter part #164090. They are designed for King Kutter RFM Series finish mowers with 4’, 5’, or 6’ cutting decks, routing the belt to maintain tension and drive the blades.

Fitment & Compatibility

Only for King Kutter RFM Series finish mowers (4’, 5’, or 6’ models). Not cross-brand compatible—do not use on other brands like Land Pride, Bush Hog, or Woods. Before buying:

• Verify your pulley diameter and shaft bore match the original. Measure your existing pulley’s outer diameter and center hole size (common sizes: 3.5"–4" OD, 5/8" or 3/4" bore).
• Check that the bearing type matches—these are likely sealed ball bearings; open or shielded bearings may not fit.
• Confirm the pulley flange shape (flat vs. crowned) matches your belt type to avoid belt slippage.

Key Things to Know

• Quality concerns: With a 3.4-star rating from only 5 reviews, expect potential fit issues or shorter lifespan than OEM. Some users report bearing failure within a season.
• Installation difficulty: Easy to moderate—requires basic hand tools (wrench, socket set) and ability to remove the deck belt. No special skills needed.
• Common gotchas: The pulley bore may be slightly undersized—check with a caliper before forcing onto the shaft. Also, verify belt alignment after installation; a misaligned pulley can cause rapid belt wear.
• No hardware included: You may need to reuse your existing bolts, washers, or spacers. Inspect them for wear first.

Should You Buy It

This is a budget-friendly option if you need a quick replacement for a King Kutter RFM mower and are comfortable with minor fitting adjustments. Skip it if you want guaranteed OEM durability or have a different brand—spend more on the exact match to avoid downtime from early failure.