Overview
Designed as a direct-fit aftermarket replacement, this trimmer head assembly replaces cracked or worn bump-feed heads on compatible string trimmers. The bump knob mechanism is a high-wear component that sees impact on every tap, and replacing the entire head is often more effective than individual part replacement. This assembly comes ready to wind with trimmer line.
Key specifications
- Replacement bump-feed trimmer head assembly
- Includes 4 piece(s)
- 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
Remove the old trimmer head by holding the drive shaft and unscrewing the head assembly. Clean the shaft threads before installing the new head. Tighten the new assembly hand-tight plus a quarter turn, then load trimmer line according to the directional arrows on the spool.
Common questions
Q: Will this 4PC T35 537185801 knob kit fit my Husqvarna T35 head that uses part number 531300194 or 537186001?
Yes, this knob kit is made for the Husqvarna T35 trimmer head and is compatible with heads referenced by 531300194 and replacement 537186001. If your existing trimmer head is the T35 style and the current knob matches 537185801, this kit is the correct fit.
Q: How do I install the 537185801 knob on my T35 trimmer head, and do I need any tools?
Installation is usually simple and does not require special tools—remove the worn knob, align the replacement knob with the spool assembly, and thread or secure it in place as the original was installed. Before reassembling, clean out any packed grass or debris inside the head so the new knob seats properly and feeds line smoothly.
Q: Why would I replace the T35 trimmer head knob instead of the whole head, and what maintenance should I do afterward?
The knob is a common wear item because it takes repeated contact and tension during line feeding, so replacing just the 537185801 knob can restore normal operation if the rest of the T35 head is still in good shape. After installation, check that the spool turns freely, inspect the spring and line path for wear, and avoid overtightening the knob to help extend its life.
