Overview
This replacement trimmer head assembly provides reliable bump-feed line advancement for string trimmers and weed eaters. When the original head cracks, the bump knob wears out, or the internal spring loses tension, line feeding becomes inconsistent. A new aftermarket trimmer head restores smooth, on-demand line advancement.
Key specifications
- Replacement bump-feed trimmer head assembly
- Tap-to-advance line feed mechanism
- Includes bump knob and internal spring
- Compatible with standard trimmer line diameters
Compatibility
This trimmer head is designed for Husqvarna string trimmers as listed above. Confirm the thread size and direction match your trimmer’s drive shaft before ordering.
Installation notes
Disconnect power from the trimmer. Unscrew the old bump knob or trimmer head from the drive shaft. Thread the new head onto the shaft, following the specified thread direction (typically left-hand or right-hand as marked). Wind fresh trimmer line onto the spool per the arrow markings before use.
Common questions
Q: Will this T25 Tap Advance trimmer head fit my Husqvarna 128LDX, or do I need to check the thread size first?
Yes, it fits the Husqvarna 128LDX as long as your unit uses the listed arbor size for this head. This replacement supports M10×1.25 left-hand and 3/8” right-hand applications, so it’s a good idea to confirm your shaft thread before installing if your machine has been modified or has a non-original gearbox.
Q: How do I install this T25 Tap Advance head on a Husqvarna 324L or 325L without damaging the threads?
First lock the gearbox shaft with the stop pin or locking tool, then remove the old head using the correct direction for your thread type. Start the new T25 head by hand to avoid cross-threading, tighten it snugly, and then test-spin it to make sure it seats evenly before use.
Q: What size trimmer line works best in this T25 Tap Advance head, and how do I keep the tap function working smoothly?
Use the line size recommended for your trimmer model and avoid overfilling the spool, because too much line can cause poor feeding or head binding. To keep the tap advance working properly, clean out grass debris regularly, inspect the eyelets for wear, and rewind the line evenly so it feeds without jamming.
