Honda 28451-Z4M-003 Starter Pulley (90° Pawls)

The Honda 28451-Z4M-003 Starter Pulley (90° Pawls) is a genuine OEM component designed for GX160 horizontal shaft engines and Honda water pumps including the WB20, WB30, WH15, WH20, WMP20, WT20, and WT30. As a direct OEM replacement, this pulley is manufactured to Honda's original specifications, ensuring the rope wraps and releases correctly every time the starter is pulled. This is the 90° pawl variant — confirm your existing pulley's pawl geometry before ordering, as the two variants are not interchangeable.

Key Features

• OEM Rope Engagement — genuine Honda construction ensures the starter rope wraps evenly around the pulley and the 90° pawls engage the cup hub cleanly, delivering a consistent, controlled pull.
• 90° Pawl Variant — this listing is specifically for the 90° pawl configuration; match this to the pawl geometry of the pulley you are replacing to ensure correct recoil starter operation.
• Broad Fitment — listed for the GX160 horizontal shaft engine and Honda WB20, WB30, WH15, WH20, WMP20, WT20, and WT30 water pumps; use the fitment table to confirm compatibility with your unit's serial number.
• Serial Number Verification Recommended — Honda supersedes recoil starter components at production breaks, so cross-check your machine's serial number against the fitment table before purchasing.

The starter pulley is the grooved disc at the heart of the recoil starter assembly. When the starter rope is pulled, it unwinds from the pulley, which rotates and drives the pawls outward to engage the engine's starter cup and spin the crankshaft for ignition. Once the engine fires, the pawls retract and the recoil spring winds the rope back onto the pulley, resetting it for the next pull. A worn, cracked, or incorrectly specified pulley can cause the rope to slip, fray, or fail to retract — leaving the engine or pump unable to start until the component is replaced.

Part Details

Compatibility & Fitment

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.