§ How-To
Replace an Auto-Feed Spool (AF-100, Ryobi, Greenworks)
A tool-free, step-by-step swap for the most common homeowner auto-feed heads — plus what to check so the new spool actually feeds.
Auto-feed heads — Black+Decker’s AF-100, Ryobi’s AC14RL3A, Greenworks’ 29252 family — are designed for tool-free spool swaps. The whole job is under two minutes, but a couple of small checks make the difference between a head that feeds reliably afterward and one that jams on the first pull.
Step 1 — Kill the power
Pull the battery, or unplug a corded unit. Never service a trimmer head with power connected — an accidental trigger with your hands in the head is exactly the injury to avoid.
Step 2 — Release the cap
Most auto-feed caps release one of two ways: two tabs you squeeze inward on opposite sides, or a quarter-turn twist. Press or twist and pull the cap straight off, then lift out the spent spool. Note how the old spool sits — which way the line threaded through the eyelets.
Step 3 — Clean and inspect (the step people skip)
With the spool out, do three quick checks:
- Clear packed grass from inside the head — wet clippings cake up and block feed.
- Inspect the eyelets — the metal or hard-plastic rings the line passes through. A worn, grooved, or sharp eyelet shreds line and is a common cause of “new spool still won’t feed.”
- Check the feed spring (if your head has one) is still seated under the spool.
Step 4 — Seat the new spool
Thread the line end(s) out through the eyelet(s), then drop the spool onto the post, matching any locating tabs or notches so it indexes correctly. For dual-line heads, feed both ends before seating. Press until it clicks, then refit the cap.
Step 5 — Test the feed
Power on. For a bump head, tap it on the ground to release line. For a true auto-feed, the line pays out as it spins / as you trigger. If nothing feeds, the usual culprits are: spool wound the wrong way, line gauge too thick, or a worn eyelet (see troubleshooting).
Getting the exact spool
Auto-feed spools are model-specific — an AF-100 won’t fit a Ryobi head. Match yours on the Black+Decker, Ryobi, or Greenworks fitment pages, or browse all trimmer parts. Not sure which spool you have? See How to Measure Your Old Spool.
§ Parts
