The Husqvarna 539990333 Lock Washer 5/8 is a genuine OEM fastening component designed for Husqvarna FS-series floor saws, including the FS4800D, FS5000D, FS6600D, FS6800D, FS7000D, FS7000DL, FS7000DMT, FS8400D, and RS8500D. As a genuine OEM part, it is manufactured to Husqvarna's exact specifications, ensuring the correct dimensions, material grade, and locking profile for a dependable connection. This lock washer delivers a direct fit into the assembly it secures, with no modification needed to match the original configuration. DHS Equipment supplies this part to help keep your floor saw operating at full capacity.
Key Features
- OEM-Grade Material and Temper — Manufactured to Husqvarna's hardness and spring-back specifications, providing the clamping force needed to prevent fastener loosening under the sustained vibration of a walk-behind floor saw.
- Correct 5/8 Sizing for Direct Installation — Matched precisely to the 5/8-inch fastener specification used in the original assembly, dropping in without adjustment or rework.
- Broad FS-Series Compatibility — Confirmed fit across multiple Husqvarna floor saw models, including the FS4800D, FS5000D, FS6600D, FS6800D, FS7000D, FS7000DL, FS7000DMT, FS8400D, Pro65G, PRO65G, and RS8500D.
- Maintains Joint Integrity Under Load — A properly functioning lock washer keeps critical fasteners torqued and seated during demanding cutting operations; a worn or absent one can allow joints to loosen and shift under continuous blade load.
- Genuine Husqvarna OEM Part — Sourced directly from Husqvarna's construction equipment parts program, cross-reference part number 539990333 against your machine's parts diagram to confirm position before installation.
A lock washer is a small but essential hardware component placed beneath a nut or bolt head to prevent the fastener from backing out due to vibration or dynamic loading. In a walk-behind floor saw like the FS-series, where a diamond blade generates significant torque and vibration through the drivetrain and blade-shaft assembly, maintaining fastener tension is critical to safe and accurate cutting. When a lock washer loses its spring or is missing entirely, the fastener it secures can gradually loosen, leading to play in the assembly, misalignment, or accelerated wear on surrounding components.
Part Details
| Part Number | 539990333 |
|---|---|
| Brand | Husqvarna |
| Part Type | Genuine OEM |
| Description | Lock Washer 5/8 |
Compatibility & Fitment
| Name | Model |
|---|---|
| Floor Saw | FS4800D |
| Floor Saw | FS5000D |
| Floor Saw | FS6600D |
| Floor Saw | FS6800D |
| Floor Saw | FS7000D |
| Floor Saw | FS7000DL |
| Floor Saw | FS8400D |
| Floor Saw | FS7000DMT |
| Floor Saw | FS5000 |
| Floor Saw | Pro65G |
| Floor Saw | RS8500D |
| Floor Saw | PRO65G |
Verify Before You Order
Fitment is machine-number and revision-specific; always confirm your model and serial number against the fitment list.
Why Buy From DHS Equipment
Every part is verified against the manufacturer's part number before it ships, so what you order is what arrives. We carry parts from leading OEM brands and our own DHS Quality Parts line of professional aftermarket components. Need help finding the right part? Our team is available to confirm compatibility whenever you need it. Orders are processed fast to keep your jobs on track. We don't just sell parts. We keep you jobsite ready.
Questions? Contact our team at [email protected] or 866-611-9369 — DHS Equipment is here to help you maintain peak performance.
