2Pcs AV17x991Li Lawn Mower Rubber Drive V-Belt Tractor Drive Belt Suitable For Most Flail Mower And Mulcher Mower(991x17mm)

What It Is

This is a set of two rubber drive V-belts (991mm x 17mm) designed to transfer power from the engine or PTO to the cutting deck on flail mowers and mulcher mowers. They replace worn or broken belts to restore blade engagement and drive performance.

Fitment & Compatibility

• Critical measurement: Belt size is 991mm (39 inches) outside length x 17mm (0.67 inches) top width. Measure your old belt (flat, not stretched) to confirm these dimensions—slight variations in length or width will cause slipping or improper tension.
• Cross reference: These belts are aftermarket replacements, not OEM. Check your mower’s manual or existing belt part number against this size. Common OEM numbers include 491-991, 991Li, or similar—but always verify by measurement.
• Deck & machine type: Designed for flail mowers and mulcher mowers (e.g., some Land Pride, Bush Hog, or compact tractor attachments). Not suitable for standard lawn tractor decks with different belt routing or smaller pulleys.
• What to check: Pulley groove width (must match 17mm), belt routing diagram, and whether your deck uses one or two belts. These come as a pair, but some decks only need one.

Key Things to Know

• Quality: Aftermarket rubber belts—adequate for light to moderate use, but may wear faster than OEM Kevlar-reinforced belts under heavy or continuous load (e.g., thick brush or wet grass).
• Installation difficulty: Moderate. You’ll need to release tension by removing a spring-loaded idler pulley or deck bolts. No special tools required, but a belt tool or pry bar helps.
• Common gotchas: New belts may feel tight initially—run the mower for 5–10 minutes at low throttle to seat them. Check tension after the first use; if it slips, adjust the idler or replace the tension spring.
• Pair note: Since you get two belts, you have a spare or can replace both simultaneously if your deck uses dual belts. Don’t mix old and new belts on the same deck—uneven wear causes vibration.

Should You Buy It

Buy these if you need a budget-friendly, direct-size replacement for a worn flail or mulcher mower drive belt and you’ve confirmed the 991x17mm dimensions match your machine. They’re a solid value for light-duty residential use or as a backup. Skip them if you need a heavy-duty OEM belt for commercial mowing or if your deck uses a different belt length or width—measure twice before ordering.